GrTessellator.cpp revision 5ad721e94682b51b9f773d95704f11990468fef6
1e9709e831954c3427d5cb839e84221a177bfedebethannicholas/* 2e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Copyright 2015 Google Inc. 3e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 4e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Use of this source code is governed by a BSD-style license that can be 5e9709e831954c3427d5cb839e84221a177bfedebethannicholas * found in the LICENSE file. 6e9709e831954c3427d5cb839e84221a177bfedebethannicholas */ 7e9709e831954c3427d5cb839e84221a177bfedebethannicholas 8e9709e831954c3427d5cb839e84221a177bfedebethannicholas#include "GrTessellator.h" 9e9709e831954c3427d5cb839e84221a177bfedebethannicholas 10f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco#include "GrDefaultGeoProcFactory.h" 11e9709e831954c3427d5cb839e84221a177bfedebethannicholas#include "GrPathUtils.h" 12e9709e831954c3427d5cb839e84221a177bfedebethannicholas 135cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby#include "SkArenaAlloc.h" 146599efffeef3168dfc68dca99c30454c5c23b859senorblanco#include "SkGeometry.h" 156599efffeef3168dfc68dca99c30454c5c23b859senorblanco#include "SkPath.h" 16e9709e831954c3427d5cb839e84221a177bfedebethannicholas 17e9709e831954c3427d5cb839e84221a177bfedebethannicholas#include <stdio.h> 18e9709e831954c3427d5cb839e84221a177bfedebethannicholas 19e9709e831954c3427d5cb839e84221a177bfedebethannicholas/* 20f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * There are six stages to the basic algorithm: 21e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 22e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 1) Linearize the path contours into piecewise linear segments (path_to_contours()). 23e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 2) Build a mesh of edges connecting the vertices (build_edges()). 24e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 3) Sort the vertices in Y (and secondarily in X) (merge_sort()). 25e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 4) Simplify the mesh by inserting new vertices at intersecting edges (simplify()). 26e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 5) Tessellate the simplified mesh into monotone polygons (tessellate()). 27e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 6) Triangulate the monotone polygons directly into a vertex buffer (polys_to_triangles()). 28e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 29f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * For screenspace antialiasing, the algorithm is modified as follows: 30f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * 31f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * Run steps 1-5 above to produce polygons. 32f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * 5b) Apply fill rules to extract boundary contours from the polygons (extract_boundaries()). 33f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * 5c) Simplify boundaries to remove "pointy" vertices which cause inversions (simplify_boundary()). 34f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * 5d) Displace edges by half a pixel inward and outward along their normals. Intersect to find 35f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * new vertices, and set zero alpha on the exterior and one alpha on the interior. Build a new 36f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * antialiased mesh from those vertices (boundary_to_aa_mesh()). 37f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * Run steps 3-6 above on the new mesh, and produce antialiased triangles. 38f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco * 39e9709e831954c3427d5cb839e84221a177bfedebethannicholas * The vertex sorting in step (3) is a merge sort, since it plays well with the linked list 40e9709e831954c3427d5cb839e84221a177bfedebethannicholas * of vertices (and the necessity of inserting new vertices on intersection). 41e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 42e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Stages (4) and (5) use an active edge list, which a list of all edges for which the 43e9709e831954c3427d5cb839e84221a177bfedebethannicholas * sweep line has crossed the top vertex, but not the bottom vertex. It's sorted 44e9709e831954c3427d5cb839e84221a177bfedebethannicholas * left-to-right based on the point where both edges are active (when both top vertices 45e9709e831954c3427d5cb839e84221a177bfedebethannicholas * have been seen, so the "lower" top vertex of the two). If the top vertices are equal 46e9709e831954c3427d5cb839e84221a177bfedebethannicholas * (shared), it's sorted based on the last point where both edges are active, so the 47e9709e831954c3427d5cb839e84221a177bfedebethannicholas * "upper" bottom vertex. 48e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 49e9709e831954c3427d5cb839e84221a177bfedebethannicholas * The most complex step is the simplification (4). It's based on the Bentley-Ottman 50e9709e831954c3427d5cb839e84221a177bfedebethannicholas * line-sweep algorithm, but due to floating point inaccuracy, the intersection points are 51e9709e831954c3427d5cb839e84221a177bfedebethannicholas * not exact and may violate the mesh topology or active edge list ordering. We 52e9709e831954c3427d5cb839e84221a177bfedebethannicholas * accommodate this by adjusting the topology of the mesh and AEL to match the intersection 53e9709e831954c3427d5cb839e84221a177bfedebethannicholas * points. This occurs in three ways: 54e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 55e9709e831954c3427d5cb839e84221a177bfedebethannicholas * A) Intersections may cause a shortened edge to no longer be ordered with respect to its 56e9709e831954c3427d5cb839e84221a177bfedebethannicholas * neighbouring edges at the top or bottom vertex. This is handled by merging the 57e9709e831954c3427d5cb839e84221a177bfedebethannicholas * edges (merge_collinear_edges()). 58e9709e831954c3427d5cb839e84221a177bfedebethannicholas * B) Intersections may cause an edge to violate the left-to-right ordering of the 59e9709e831954c3427d5cb839e84221a177bfedebethannicholas * active edge list. This is handled by splitting the neighbour edge on the 60e9709e831954c3427d5cb839e84221a177bfedebethannicholas * intersected vertex (cleanup_active_edges()). 61e9709e831954c3427d5cb839e84221a177bfedebethannicholas * C) Shortening an edge may cause an active edge to become inactive or an inactive edge 62e9709e831954c3427d5cb839e84221a177bfedebethannicholas * to become active. This is handled by removing or inserting the edge in the active 63e9709e831954c3427d5cb839e84221a177bfedebethannicholas * edge list (fix_active_state()). 64e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 65e9709e831954c3427d5cb839e84221a177bfedebethannicholas * The tessellation steps (5) and (6) are based on "Triangulating Simple Polygons and 66e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Equivalent Problems" (Fournier and Montuno); also a line-sweep algorithm. Note that it 67e9709e831954c3427d5cb839e84221a177bfedebethannicholas * currently uses a linked list for the active edge list, rather than a 2-3 tree as the 68e9709e831954c3427d5cb839e84221a177bfedebethannicholas * paper describes. The 2-3 tree gives O(lg N) lookups, but insertion and removal also 69e9709e831954c3427d5cb839e84221a177bfedebethannicholas * become O(lg N). In all the test cases, it was found that the cost of frequent O(lg N) 70e9709e831954c3427d5cb839e84221a177bfedebethannicholas * insertions and removals was greater than the cost of infrequent O(N) lookups with the 71e9709e831954c3427d5cb839e84221a177bfedebethannicholas * linked list implementation. With the latter, all removals are O(1), and most insertions 72e9709e831954c3427d5cb839e84221a177bfedebethannicholas * are O(1), since we know the adjacent edge in the active edge list based on the topology. 73e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Only type 2 vertices (see paper) require the O(N) lookups, and these are much less 74e9709e831954c3427d5cb839e84221a177bfedebethannicholas * frequent. There may be other data structures worth investigating, however. 75e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 76e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Note that the orientation of the line sweep algorithms is determined by the aspect ratio of the 77e9709e831954c3427d5cb839e84221a177bfedebethannicholas * path bounds. When the path is taller than it is wide, we sort vertices based on increasing Y 78e9709e831954c3427d5cb839e84221a177bfedebethannicholas * coordinate, and secondarily by increasing X coordinate. When the path is wider than it is tall, 79e9709e831954c3427d5cb839e84221a177bfedebethannicholas * we sort by increasing X coordinate, but secondarily by *decreasing* Y coordinate. This is so 80e9709e831954c3427d5cb839e84221a177bfedebethannicholas * that the "left" and "right" orientation in the code remains correct (edges to the left are 81e9709e831954c3427d5cb839e84221a177bfedebethannicholas * increasing in Y; edges to the right are decreasing in Y). That is, the setting rotates 90 82e9709e831954c3427d5cb839e84221a177bfedebethannicholas * degrees counterclockwise, rather that transposing. 83e9709e831954c3427d5cb839e84221a177bfedebethannicholas */ 84e9709e831954c3427d5cb839e84221a177bfedebethannicholas 85e9709e831954c3427d5cb839e84221a177bfedebethannicholas#define LOGGING_ENABLED 0 86e9709e831954c3427d5cb839e84221a177bfedebethannicholas 87e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 88e9709e831954c3427d5cb839e84221a177bfedebethannicholas#define LOG printf 89e9709e831954c3427d5cb839e84221a177bfedebethannicholas#else 90e9709e831954c3427d5cb839e84221a177bfedebethannicholas#define LOG(...) 91e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 92e9709e831954c3427d5cb839e84221a177bfedebethannicholas 93e9709e831954c3427d5cb839e84221a177bfedebethannicholasnamespace { 94e9709e831954c3427d5cb839e84221a177bfedebethannicholas 9511f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen Whiteconst int kArenaChunkSize = 16 * 1024; 9611f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White 97e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Vertex; 98e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Edge; 99e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Poly; 100e9709e831954c3427d5cb839e84221a177bfedebethannicholas 101e9709e831954c3427d5cb839e84221a177bfedebethannicholastemplate <class T, T* T::*Prev, T* T::*Next> 102e6eaa320e8dac34396dc364aa0863574d7b5291csenorblancovoid list_insert(T* t, T* prev, T* next, T** head, T** tail) { 103e9709e831954c3427d5cb839e84221a177bfedebethannicholas t->*Prev = prev; 104e9709e831954c3427d5cb839e84221a177bfedebethannicholas t->*Next = next; 105e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (prev) { 106e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->*Next = t; 107e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (head) { 108e9709e831954c3427d5cb839e84221a177bfedebethannicholas *head = t; 109e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 110e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (next) { 111e9709e831954c3427d5cb839e84221a177bfedebethannicholas next->*Prev = t; 112e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (tail) { 113e9709e831954c3427d5cb839e84221a177bfedebethannicholas *tail = t; 114e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 115e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 116e9709e831954c3427d5cb839e84221a177bfedebethannicholas 117e9709e831954c3427d5cb839e84221a177bfedebethannicholastemplate <class T, T* T::*Prev, T* T::*Next> 118e6eaa320e8dac34396dc364aa0863574d7b5291csenorblancovoid list_remove(T* t, T** head, T** tail) { 119e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (t->*Prev) { 120e9709e831954c3427d5cb839e84221a177bfedebethannicholas t->*Prev->*Next = t->*Next; 121e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (head) { 122e9709e831954c3427d5cb839e84221a177bfedebethannicholas *head = t->*Next; 123e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 124e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (t->*Next) { 125e9709e831954c3427d5cb839e84221a177bfedebethannicholas t->*Next->*Prev = t->*Prev; 126e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (tail) { 127e9709e831954c3427d5cb839e84221a177bfedebethannicholas *tail = t->*Prev; 128e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 129e9709e831954c3427d5cb839e84221a177bfedebethannicholas t->*Prev = t->*Next = nullptr; 130e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 131e9709e831954c3427d5cb839e84221a177bfedebethannicholas 132e9709e831954c3427d5cb839e84221a177bfedebethannicholas/** 133e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Vertices are used in three ways: first, the path contours are converted into a 134e9709e831954c3427d5cb839e84221a177bfedebethannicholas * circularly-linked list of Vertices for each contour. After edge construction, the same Vertices 135e9709e831954c3427d5cb839e84221a177bfedebethannicholas * are re-ordered by the merge sort according to the sweep_lt comparator (usually, increasing 136e9709e831954c3427d5cb839e84221a177bfedebethannicholas * in Y) using the same fPrev/fNext pointers that were used for the contours, to avoid 137e9709e831954c3427d5cb839e84221a177bfedebethannicholas * reallocation. Finally, MonotonePolys are built containing a circularly-linked list of 138e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Vertices. (Currently, those Vertices are newly-allocated for the MonotonePolys, since 139e9709e831954c3427d5cb839e84221a177bfedebethannicholas * an individual Vertex from the path mesh may belong to multiple 140e9709e831954c3427d5cb839e84221a177bfedebethannicholas * MonotonePolys, so the original Vertices cannot be re-used. 141e9709e831954c3427d5cb839e84221a177bfedebethannicholas */ 142e9709e831954c3427d5cb839e84221a177bfedebethannicholas 143e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Vertex { 144f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex(const SkPoint& point, uint8_t alpha) 145e9709e831954c3427d5cb839e84221a177bfedebethannicholas : fPoint(point), fPrev(nullptr), fNext(nullptr) 146e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fFirstEdgeAbove(nullptr), fLastEdgeAbove(nullptr) 147e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fFirstEdgeBelow(nullptr), fLastEdgeBelow(nullptr) 148e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fProcessed(false) 149f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco , fAlpha(alpha) 150e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 151e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fID (-1.0f) 152e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 153e9709e831954c3427d5cb839e84221a177bfedebethannicholas {} 154e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint fPoint; // Vertex position 155e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* fPrev; // Linked list of contours, then Y-sorted vertices. 156e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* fNext; // " 157e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fFirstEdgeAbove; // Linked list of edges above this vertex. 158e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fLastEdgeAbove; // " 159e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fFirstEdgeBelow; // Linked list of edges below this vertex. 160e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fLastEdgeBelow; // " 161e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool fProcessed; // Has this vertex been seen in simplify()? 162f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco uint8_t fAlpha; 163e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 164e9709e831954c3427d5cb839e84221a177bfedebethannicholas float fID; // Identifier used for logging. 165e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 166e9709e831954c3427d5cb839e84221a177bfedebethannicholas}; 167e9709e831954c3427d5cb839e84221a177bfedebethannicholas 168e9709e831954c3427d5cb839e84221a177bfedebethannicholas/***************************************************************************************/ 169e9709e831954c3427d5cb839e84221a177bfedebethannicholas 170f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancostruct AAParams { 171f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco bool fTweakAlpha; 172f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco GrColor fColor; 173f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco}; 174f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 175e9709e831954c3427d5cb839e84221a177bfedebethannicholastypedef bool (*CompareFunc)(const SkPoint& a, const SkPoint& b); 176e9709e831954c3427d5cb839e84221a177bfedebethannicholas 177e9709e831954c3427d5cb839e84221a177bfedebethannicholasbool sweep_lt_horiz(const SkPoint& a, const SkPoint& b) { 17816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return a.fX < b.fX || (a.fX == b.fX && a.fY > b.fY); 179e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 180e9709e831954c3427d5cb839e84221a177bfedebethannicholas 181e9709e831954c3427d5cb839e84221a177bfedebethannicholasbool sweep_lt_vert(const SkPoint& a, const SkPoint& b) { 18216a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return a.fY < b.fY || (a.fY == b.fY && a.fX < b.fX); 183e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 184e9709e831954c3427d5cb839e84221a177bfedebethannicholas 185e9709e831954c3427d5cb839e84221a177bfedebethannicholasbool sweep_gt_horiz(const SkPoint& a, const SkPoint& b) { 18616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return a.fX > b.fX || (a.fX == b.fX && a.fY < b.fY); 187e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 188e9709e831954c3427d5cb839e84221a177bfedebethannicholas 189e9709e831954c3427d5cb839e84221a177bfedebethannicholasbool sweep_gt_vert(const SkPoint& a, const SkPoint& b) { 19016a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return a.fY > b.fY || (a.fY == b.fY && a.fX > b.fX); 191e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 192e9709e831954c3427d5cb839e84221a177bfedebethannicholas 19316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen Whitestruct Comparator { 19416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White enum class Direction { kVertical, kHorizontal }; 19516a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Comparator(Direction direction) : fDirection(direction) {} 19616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White bool sweep_lt(const SkPoint& a, const SkPoint& b) const { 19716a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return fDirection == Direction::kHorizontal ? sweep_lt_horiz(a, b) : sweep_lt_vert(a, b); 19816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } 19916a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White bool sweep_gt(const SkPoint& a, const SkPoint& b) const { 20016a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return fDirection == Direction::kHorizontal ? sweep_gt_horiz(a, b) : sweep_gt_vert(a, b); 20116a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } 20216a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Direction fDirection; 20316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White}; 20416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White 205f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancoinline void* emit_vertex(Vertex* v, const AAParams* aaParams, void* data) { 206f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (!aaParams) { 207f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkPoint* d = static_cast<SkPoint*>(data); 208f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco *d++ = v->fPoint; 209f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return d; 210f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 211f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (aaParams->fTweakAlpha) { 212f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco auto d = static_cast<GrDefaultGeoProcFactory::PositionColorAttr*>(data); 213f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d->fPosition = v->fPoint; 2148c8fceff4d4e8ec09f29748d77ed5510697a2995lsalzman d->fColor = SkAlphaMulQ(aaParams->fColor, SkAlpha255To256(v->fAlpha)); 215f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d++; 216f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return d; 217f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 218f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco auto d = static_cast<GrDefaultGeoProcFactory::PositionColorCoverageAttr*>(data); 219f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d->fPosition = v->fPoint; 220f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d->fColor = aaParams->fColor; 221f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d->fCoverage = GrNormalizeByteToFloat(v->fAlpha); 222f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco d++; 223f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return d; 224e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 225e9709e831954c3427d5cb839e84221a177bfedebethannicholas 226f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancovoid* emit_triangle(Vertex* v0, Vertex* v1, Vertex* v2, const AAParams* aaParams, void* data) { 22792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White LOG("emit_triangle (%g, %g) %d\n", v0->fPoint.fX, v0->fPoint.fY, v0->fAlpha); 22892eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White LOG(" (%g, %g) %d\n", v1->fPoint.fX, v1->fPoint.fY, v1->fAlpha); 22992eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White LOG(" (%g, %g) %d\n", v2->fPoint.fX, v2->fPoint.fY, v2->fAlpha); 230f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco#if TESSELLATOR_WIREFRAME 231f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v0, aaParams, data); 232f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v1, aaParams, data); 233f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v1, aaParams, data); 234f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v2, aaParams, data); 235f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v2, aaParams, data); 236f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v0, aaParams, data); 237e9709e831954c3427d5cb839e84221a177bfedebethannicholas#else 238f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v0, aaParams, data); 239f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v1, aaParams, data); 240f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_vertex(v2, aaParams, data); 241e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 242e9709e831954c3427d5cb839e84221a177bfedebethannicholas return data; 243e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 244e9709e831954c3427d5cb839e84221a177bfedebethannicholas 245e6eaa320e8dac34396dc364aa0863574d7b5291csenorblancostruct VertexList { 246e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco VertexList() : fHead(nullptr), fTail(nullptr) {} 24716a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White VertexList(Vertex* head, Vertex* tail) : fHead(head), fTail(tail) {} 248e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco Vertex* fHead; 249e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco Vertex* fTail; 250e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco void insert(Vertex* v, Vertex* prev, Vertex* next) { 251e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco list_insert<Vertex, &Vertex::fPrev, &Vertex::fNext>(v, prev, next, &fHead, &fTail); 252e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco } 253e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco void append(Vertex* v) { 254e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco insert(v, fTail, nullptr); 255e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco } 256e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco void prepend(Vertex* v) { 257e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco insert(v, nullptr, fHead); 258e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco } 259bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White void remove(Vertex* v) { 260bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White list_remove<Vertex, &Vertex::fPrev, &Vertex::fNext>(v, &fHead, &fTail); 261bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White } 262f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void close() { 263f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (fHead && fTail) { 264f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco fTail->fNext = fHead; 265f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco fHead->fPrev = fTail; 266f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 267f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 268e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco}; 269e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco 270f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// Round to nearest quarter-pixel. This is used for screenspace tessellation. 271f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 272f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancoinline void round(SkPoint* p) { 273f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco p->fX = SkScalarRoundToScalar(p->fX * SkFloatToScalar(4.0f)) * SkFloatToScalar(0.25f); 274f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco p->fY = SkScalarRoundToScalar(p->fY * SkFloatToScalar(4.0f)) * SkFloatToScalar(0.25f); 275f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 276f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 27749df8d17c56ee08ecf860289d501913d356f67dcsenorblanco// A line equation in implicit form. fA * x + fB * y + fC = 0, for all points (x, y) on the line. 27849df8d17c56ee08ecf860289d501913d356f67dcsenorblancostruct Line { 27949df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line(Vertex* p, Vertex* q) : Line(p->fPoint, q->fPoint) {} 28049df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line(const SkPoint& p, const SkPoint& q) 28149df8d17c56ee08ecf860289d501913d356f67dcsenorblanco : fA(static_cast<double>(q.fY) - p.fY) // a = dY 28249df8d17c56ee08ecf860289d501913d356f67dcsenorblanco , fB(static_cast<double>(p.fX) - q.fX) // b = -dX 28349df8d17c56ee08ecf860289d501913d356f67dcsenorblanco , fC(static_cast<double>(p.fY) * q.fX - // c = cross(q, p) 28449df8d17c56ee08ecf860289d501913d356f67dcsenorblanco static_cast<double>(p.fX) * q.fY) {} 28549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double dist(const SkPoint& p) const { 28649df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return fA * p.fX + fB * p.fY + fC; 28749df8d17c56ee08ecf860289d501913d356f67dcsenorblanco } 28849df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double magSq() const { 28949df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return fA * fA + fB * fB; 29049df8d17c56ee08ecf860289d501913d356f67dcsenorblanco } 29149df8d17c56ee08ecf860289d501913d356f67dcsenorblanco 29249df8d17c56ee08ecf860289d501913d356f67dcsenorblanco // Compute the intersection of two (infinite) Lines. 29349df8d17c56ee08ecf860289d501913d356f67dcsenorblanco bool intersect(const Line& other, SkPoint* point) { 29449df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double denom = fA * other.fB - fB * other.fA; 29549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco if (denom == 0.0) { 29649df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return false; 29749df8d17c56ee08ecf860289d501913d356f67dcsenorblanco } 29849df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double scale = 1.0f / denom; 29949df8d17c56ee08ecf860289d501913d356f67dcsenorblanco point->fX = SkDoubleToScalar((fB * other.fC - other.fB * fC) * scale); 30049df8d17c56ee08ecf860289d501913d356f67dcsenorblanco point->fY = SkDoubleToScalar((other.fA * fC - fA * other.fC) * scale); 30149df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return true; 30249df8d17c56ee08ecf860289d501913d356f67dcsenorblanco } 30349df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double fA, fB, fC; 30449df8d17c56ee08ecf860289d501913d356f67dcsenorblanco}; 30549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco 306e9709e831954c3427d5cb839e84221a177bfedebethannicholas/** 307e9709e831954c3427d5cb839e84221a177bfedebethannicholas * An Edge joins a top Vertex to a bottom Vertex. Edge ordering for the list of "edges above" and 308e9709e831954c3427d5cb839e84221a177bfedebethannicholas * "edge below" a vertex as well as for the active edge list is handled by isLeftOf()/isRightOf(). 309e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Note that an Edge will give occasionally dist() != 0 for its own endpoints (because floating 310e9709e831954c3427d5cb839e84221a177bfedebethannicholas * point). For speed, that case is only tested by the callers which require it (e.g., 311e9709e831954c3427d5cb839e84221a177bfedebethannicholas * cleanup_active_edges()). Edges also handle checking for intersection with other edges. 312e9709e831954c3427d5cb839e84221a177bfedebethannicholas * Currently, this converts the edges to the parametric form, in order to avoid doing a division 313e9709e831954c3427d5cb839e84221a177bfedebethannicholas * until an intersection has been confirmed. This is slightly slower in the "found" case, but 314e9709e831954c3427d5cb839e84221a177bfedebethannicholas * a lot faster in the "not found" case. 315e9709e831954c3427d5cb839e84221a177bfedebethannicholas * 316e9709e831954c3427d5cb839e84221a177bfedebethannicholas * The coefficients of the line equation stored in double precision to avoid catastrphic 317e9709e831954c3427d5cb839e84221a177bfedebethannicholas * cancellation in the isLeftOf() and isRightOf() checks. Using doubles ensures that the result is 318e9709e831954c3427d5cb839e84221a177bfedebethannicholas * correct in float, since it's a polynomial of degree 2. The intersect() function, being 319e9709e831954c3427d5cb839e84221a177bfedebethannicholas * degree 5, is still subject to catastrophic cancellation. We deal with that by assuming its 320e9709e831954c3427d5cb839e84221a177bfedebethannicholas * output may be incorrect, and adjusting the mesh topology to match (see comment at the top of 321e9709e831954c3427d5cb839e84221a177bfedebethannicholas * this file). 322e9709e831954c3427d5cb839e84221a177bfedebethannicholas */ 323e9709e831954c3427d5cb839e84221a177bfedebethannicholas 324e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Edge { 3252f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White enum class Type { kInner, kOuter, kConnector }; 3262f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White Edge(Vertex* top, Vertex* bottom, int winding, Type type) 327e9709e831954c3427d5cb839e84221a177bfedebethannicholas : fWinding(winding) 328e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fTop(top) 329e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fBottom(bottom) 3302f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White , fType(type) 331e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fLeft(nullptr) 332e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fRight(nullptr) 333e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fPrevEdgeAbove(nullptr) 334e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fNextEdgeAbove(nullptr) 335e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fPrevEdgeBelow(nullptr) 336e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fNextEdgeBelow(nullptr) 337e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fLeftPoly(nullptr) 338531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fRightPoly(nullptr) 339531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fLeftPolyPrev(nullptr) 340531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fLeftPolyNext(nullptr) 341531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fRightPolyPrev(nullptr) 34270f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco , fRightPolyNext(nullptr) 34370f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco , fUsedInLeftPoly(false) 34449df8d17c56ee08ecf860289d501913d356f67dcsenorblanco , fUsedInRightPoly(false) 34549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco , fLine(top, bottom) { 346e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 347e9709e831954c3427d5cb839e84221a177bfedebethannicholas int fWinding; // 1 == edge goes downward; -1 = edge goes upward. 348e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* fTop; // The top vertex in vertex-sort-order (sweep_lt). 349e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* fBottom; // The bottom vertex in vertex-sort-order. 3502f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White Type fType; 351e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fLeft; // The linked list of edges in the active edge list. 352e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fRight; // " 353e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fPrevEdgeAbove; // The linked list of edges in the bottom Vertex's "edges above". 354e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fNextEdgeAbove; // " 355e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fPrevEdgeBelow; // The linked list of edges in the top Vertex's "edges below". 356e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* fNextEdgeBelow; // " 357e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* fLeftPoly; // The Poly to the left of this edge, if any. 358e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* fRightPoly; // The Poly to the right of this edge, if any. 359531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fLeftPolyPrev; 360531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fLeftPolyNext; 361531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fRightPolyPrev; 362531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fRightPolyNext; 36370f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco bool fUsedInLeftPoly; 36470f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco bool fUsedInRightPoly; 36549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line fLine; 366e9709e831954c3427d5cb839e84221a177bfedebethannicholas double dist(const SkPoint& p) const { 36749df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return fLine.dist(p); 368e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 369e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool isRightOf(Vertex* v) const { 37049df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return fLine.dist(v->fPoint) < 0.0; 371e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 372e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool isLeftOf(Vertex* v) const { 37349df8d17c56ee08ecf860289d501913d356f67dcsenorblanco return fLine.dist(v->fPoint) > 0.0; 374e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 375e9709e831954c3427d5cb839e84221a177bfedebethannicholas void recompute() { 37649df8d17c56ee08ecf860289d501913d356f67dcsenorblanco fLine = Line(fTop, fBottom); 377e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 378dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner bool intersect(const Edge& other, SkPoint* p, uint8_t* alpha = nullptr) { 379e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("intersecting %g -> %g with %g -> %g\n", 380e9709e831954c3427d5cb839e84221a177bfedebethannicholas fTop->fID, fBottom->fID, 381e9709e831954c3427d5cb839e84221a177bfedebethannicholas other.fTop->fID, other.fBottom->fID); 382e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (fTop == other.fTop || fBottom == other.fBottom) { 383e9709e831954c3427d5cb839e84221a177bfedebethannicholas return false; 384e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 38549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double denom = fLine.fA * other.fLine.fB - fLine.fB * other.fLine.fA; 386e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (denom == 0.0) { 387e9709e831954c3427d5cb839e84221a177bfedebethannicholas return false; 388e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 3898a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White double dx = static_cast<double>(other.fTop->fPoint.fX) - fTop->fPoint.fX; 3908a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White double dy = static_cast<double>(other.fTop->fPoint.fY) - fTop->fPoint.fY; 3918a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White double sNumer = dy * other.fLine.fB + dx * other.fLine.fA; 3928a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White double tNumer = dy * fLine.fB + dx * fLine.fA; 393e9709e831954c3427d5cb839e84221a177bfedebethannicholas // If (sNumer / denom) or (tNumer / denom) is not in [0..1], exit early. 394e9709e831954c3427d5cb839e84221a177bfedebethannicholas // This saves us doing the divide below unless absolutely necessary. 395e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (denom > 0.0 ? (sNumer < 0.0 || sNumer > denom || tNumer < 0.0 || tNumer > denom) 396e9709e831954c3427d5cb839e84221a177bfedebethannicholas : (sNumer > 0.0 || sNumer < denom || tNumer > 0.0 || tNumer < denom)) { 397e9709e831954c3427d5cb839e84221a177bfedebethannicholas return false; 398e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 399e9709e831954c3427d5cb839e84221a177bfedebethannicholas double s = sNumer / denom; 400e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(s >= 0.0 && s <= 1.0); 40149df8d17c56ee08ecf860289d501913d356f67dcsenorblanco p->fX = SkDoubleToScalar(fTop->fPoint.fX - s * fLine.fB); 40249df8d17c56ee08ecf860289d501913d356f67dcsenorblanco p->fY = SkDoubleToScalar(fTop->fPoint.fY + s * fLine.fA); 40356158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White if (alpha) { 40492eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White if (fType == Type::kConnector) { 40592eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White *alpha = (1.0 - s) * fTop->fAlpha + s * fBottom->fAlpha; 40692eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White } else if (other.fType == Type::kConnector) { 40792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White double t = tNumer / denom; 40892eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White *alpha = (1.0 - t) * other.fTop->fAlpha + t * other.fBottom->fAlpha; 40956158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White } else if (fType == Type::kOuter && other.fType == Type::kOuter) { 41056158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White *alpha = 0; 41156158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White } else { 41292eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White *alpha = 255; 41356158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White } 41456158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White } 415e9709e831954c3427d5cb839e84221a177bfedebethannicholas return true; 416e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 417f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco}; 418f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 419f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancostruct EdgeList { 4205ad721e94682b51b9f773d95704f11990468fef6Stephen White EdgeList() : fHead(nullptr), fTail(nullptr) {} 421f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Edge* fHead; 422f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Edge* fTail; 423f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void insert(Edge* edge, Edge* prev, Edge* next) { 424f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco list_insert<Edge, &Edge::fLeft, &Edge::fRight>(edge, prev, next, &fHead, &fTail); 425f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 426f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void append(Edge* e) { 427f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco insert(e, fTail, nullptr); 428f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 429f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void remove(Edge* edge) { 430f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco list_remove<Edge, &Edge::fLeft, &Edge::fRight>(edge, &fHead, &fTail); 431f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 432f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void close() { 433f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (fHead && fTail) { 434f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco fTail->fRight = fHead; 435f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco fHead->fLeft = fTail; 436f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 437f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 438f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco bool contains(Edge* edge) const { 439f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return edge->fLeft || edge->fRight || fHead == edge; 440e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 441e9709e831954c3427d5cb839e84221a177bfedebethannicholas}; 442e9709e831954c3427d5cb839e84221a177bfedebethannicholas 443e9709e831954c3427d5cb839e84221a177bfedebethannicholas/***************************************************************************************/ 444e9709e831954c3427d5cb839e84221a177bfedebethannicholas 445e9709e831954c3427d5cb839e84221a177bfedebethannicholasstruct Poly { 446531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Poly(Vertex* v, int winding) 447531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco : fFirstVertex(v) 448531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fWinding(winding) 449e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fHead(nullptr) 450e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fTail(nullptr) 451e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fNext(nullptr) 452e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fPartner(nullptr) 453e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fCount(0) 454e9709e831954c3427d5cb839e84221a177bfedebethannicholas { 455e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 456e9709e831954c3427d5cb839e84221a177bfedebethannicholas static int gID = 0; 457e9709e831954c3427d5cb839e84221a177bfedebethannicholas fID = gID++; 458e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("*** created Poly %d\n", fID); 459e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 460e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 461531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco typedef enum { kLeft_Side, kRight_Side } Side; 462e9709e831954c3427d5cb839e84221a177bfedebethannicholas struct MonotonePoly { 463531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco MonotonePoly(Edge* edge, Side side) 464531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco : fSide(side) 465531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fFirstEdge(nullptr) 466531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fLastEdge(nullptr) 467e9709e831954c3427d5cb839e84221a177bfedebethannicholas , fPrev(nullptr) 468531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco , fNext(nullptr) { 469531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco this->addEdge(edge); 470531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } 471e9709e831954c3427d5cb839e84221a177bfedebethannicholas Side fSide; 472531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fFirstEdge; 473531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* fLastEdge; 474e9709e831954c3427d5cb839e84221a177bfedebethannicholas MonotonePoly* fPrev; 475e9709e831954c3427d5cb839e84221a177bfedebethannicholas MonotonePoly* fNext; 476531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco void addEdge(Edge* edge) { 477e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco if (fSide == kRight_Side) { 478212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco SkASSERT(!edge->fUsedInRightPoly); 479531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco list_insert<Edge, &Edge::fRightPolyPrev, &Edge::fRightPolyNext>( 480531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco edge, fLastEdge, nullptr, &fFirstEdge, &fLastEdge); 48170f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco edge->fUsedInRightPoly = true; 482e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 483212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco SkASSERT(!edge->fUsedInLeftPoly); 484531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco list_insert<Edge, &Edge::fLeftPolyPrev, &Edge::fLeftPolyNext>( 485531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco edge, fLastEdge, nullptr, &fFirstEdge, &fLastEdge); 48670f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco edge->fUsedInLeftPoly = true; 487e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 488e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 489e9709e831954c3427d5cb839e84221a177bfedebethannicholas 490f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void* emit(const AAParams* aaParams, void* data) { 491531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Edge* e = fFirstEdge; 492531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco e->fTop->fPrev = e->fTop->fNext = nullptr; 493531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco VertexList vertices; 494531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco vertices.append(e->fTop); 495531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco while (e != nullptr) { 496531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco e->fBottom->fPrev = e->fBottom->fNext = nullptr; 497531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco if (kRight_Side == fSide) { 498531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco vertices.append(e->fBottom); 499531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco e = e->fRightPolyNext; 500531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } else { 501531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco vertices.prepend(e->fBottom); 502531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco e = e->fLeftPolyNext; 503531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } 504531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } 505531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Vertex* first = vertices.fHead; 506e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* v = first->fNext; 507531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco while (v != vertices.fTail) { 508e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(v && v->fPrev && v->fNext); 509e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prev = v->fPrev; 510e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* curr = v; 511e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* next = v->fNext; 512e9709e831954c3427d5cb839e84221a177bfedebethannicholas double ax = static_cast<double>(curr->fPoint.fX) - prev->fPoint.fX; 513e9709e831954c3427d5cb839e84221a177bfedebethannicholas double ay = static_cast<double>(curr->fPoint.fY) - prev->fPoint.fY; 514e9709e831954c3427d5cb839e84221a177bfedebethannicholas double bx = static_cast<double>(next->fPoint.fX) - curr->fPoint.fX; 515e9709e831954c3427d5cb839e84221a177bfedebethannicholas double by = static_cast<double>(next->fPoint.fY) - curr->fPoint.fY; 516e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (ax * by - ay * bx >= 0.0) { 517f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = emit_triangle(prev, curr, next, aaParams, data); 518e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPrev->fNext = v->fNext; 519e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fNext->fPrev = v->fPrev; 520e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fPrev == first) { 521e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = v->fNext; 522e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 523e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = v->fPrev; 524e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 525e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 526e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = v->fNext; 527e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 528e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 529e9709e831954c3427d5cb839e84221a177bfedebethannicholas return data; 530e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 531e9709e831954c3427d5cb839e84221a177bfedebethannicholas }; 5325cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Poly* addEdge(Edge* e, Side side, SkArenaAlloc& alloc) { 53370f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco LOG("addEdge (%g -> %g) to poly %d, %s side\n", 53470f5251cc59191040a14cd0f1567aa2129e1f7c6senorblanco e->fTop->fID, e->fBottom->fID, fID, side == kLeft_Side ? "left" : "right"); 535e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* partner = fPartner; 536e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* poly = this; 537212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco if (side == kRight_Side) { 538212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco if (e->fUsedInRightPoly) { 539212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco return this; 540212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco } 541212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco } else { 542212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco if (e->fUsedInLeftPoly) { 543212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco return this; 544212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco } 545212c7c389e81053b84a3ed7775f2031d76d5ee70senorblanco } 546e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (partner) { 547e9709e831954c3427d5cb839e84221a177bfedebethannicholas fPartner = partner->fPartner = nullptr; 548e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 549531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco if (!fTail) { 5505cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby fHead = fTail = alloc.make<MonotonePoly>(e, side); 551531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fCount += 2; 55293e3fff79eaaa86bc2fb740a42111a074ccc73absenorblanco } else if (e->fBottom == fTail->fLastEdge->fBottom) { 55393e3fff79eaaa86bc2fb740a42111a074ccc73absenorblanco return poly; 554531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } else if (side == fTail->fSide) { 555531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fTail->addEdge(e); 556531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fCount++; 557531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } else { 5585cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby e = alloc.make<Edge>(fTail->fLastEdge->fBottom, e->fBottom, 1, Edge::Type::kInner); 559531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fTail->addEdge(e); 560531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fCount++; 561e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (partner) { 562531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco partner->addEdge(e, side, alloc); 563e9709e831954c3427d5cb839e84221a177bfedebethannicholas poly = partner; 564e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 5655cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby MonotonePoly* m = alloc.make<MonotonePoly>(e, side); 566531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco m->fPrev = fTail; 567531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fTail->fNext = m; 568531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco fTail = m; 569e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 570e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 571e9709e831954c3427d5cb839e84221a177bfedebethannicholas return poly; 572e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 573f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void* emit(const AAParams* aaParams, void *data) { 574e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (fCount < 3) { 575e9709e831954c3427d5cb839e84221a177bfedebethannicholas return data; 576e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 577e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("emit() %d, size %d\n", fID, fCount); 578e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (MonotonePoly* m = fHead; m != nullptr; m = m->fNext) { 579f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = m->emit(aaParams, data); 580e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 581e9709e831954c3427d5cb839e84221a177bfedebethannicholas return data; 582e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 583531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Vertex* lastVertex() const { return fTail ? fTail->fLastEdge->fBottom : fFirstVertex; } 584531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco Vertex* fFirstVertex; 585e9709e831954c3427d5cb839e84221a177bfedebethannicholas int fWinding; 586e9709e831954c3427d5cb839e84221a177bfedebethannicholas MonotonePoly* fHead; 587e9709e831954c3427d5cb839e84221a177bfedebethannicholas MonotonePoly* fTail; 588e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* fNext; 589e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* fPartner; 590e9709e831954c3427d5cb839e84221a177bfedebethannicholas int fCount; 591e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 592e9709e831954c3427d5cb839e84221a177bfedebethannicholas int fID; 593e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 594e9709e831954c3427d5cb839e84221a177bfedebethannicholas}; 595e9709e831954c3427d5cb839e84221a177bfedebethannicholas 596e9709e831954c3427d5cb839e84221a177bfedebethannicholas/***************************************************************************************/ 597e9709e831954c3427d5cb839e84221a177bfedebethannicholas 598e9709e831954c3427d5cb839e84221a177bfedebethannicholasbool coincident(const SkPoint& a, const SkPoint& b) { 599e9709e831954c3427d5cb839e84221a177bfedebethannicholas return a == b; 600e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 601e9709e831954c3427d5cb839e84221a177bfedebethannicholas 6025cdc9dda330db41d34e452a91b6b0995b5a57626Herb DerbyPoly* new_poly(Poly** head, Vertex* v, int winding, SkArenaAlloc& alloc) { 6035cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Poly* poly = alloc.make<Poly>(v, winding); 604e9709e831954c3427d5cb839e84221a177bfedebethannicholas poly->fNext = *head; 605e9709e831954c3427d5cb839e84221a177bfedebethannicholas *head = poly; 606e9709e831954c3427d5cb839e84221a177bfedebethannicholas return poly; 607e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 608e9709e831954c3427d5cb839e84221a177bfedebethannicholas 609e9709e831954c3427d5cb839e84221a177bfedebethannicholasVertex* append_point_to_contour(const SkPoint& p, Vertex* prev, Vertex** head, 6105cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 6115cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Vertex* v = alloc.make<Vertex>(p, 255); 612e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 613e9709e831954c3427d5cb839e84221a177bfedebethannicholas static float gID = 0.0f; 614e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fID = gID++; 615e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 616e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (prev) { 617e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = v; 618e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPrev = prev; 619e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 620e9709e831954c3427d5cb839e84221a177bfedebethannicholas *head = v; 621e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 622e9709e831954c3427d5cb839e84221a177bfedebethannicholas return v; 623e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 624e9709e831954c3427d5cb839e84221a177bfedebethannicholas 625e9709e831954c3427d5cb839e84221a177bfedebethannicholasVertex* generate_quadratic_points(const SkPoint& p0, 626e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint& p1, 627e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint& p2, 628e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar tolSqd, 629e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prev, 630e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex** head, 631e9709e831954c3427d5cb839e84221a177bfedebethannicholas int pointsLeft, 6325cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 633e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar d = p1.distanceToLineSegmentBetweenSqd(p0, p2); 634e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (pointsLeft < 2 || d < tolSqd || !SkScalarIsFinite(d)) { 635e9709e831954c3427d5cb839e84221a177bfedebethannicholas return append_point_to_contour(p2, prev, head, alloc); 636e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 637e9709e831954c3427d5cb839e84221a177bfedebethannicholas 638e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint q[] = { 639e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(p0.fX, p1.fX), SkScalarAve(p0.fY, p1.fY) }, 640e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(p1.fX, p2.fX), SkScalarAve(p1.fY, p2.fY) }, 641e9709e831954c3427d5cb839e84221a177bfedebethannicholas }; 642e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint r = { SkScalarAve(q[0].fX, q[1].fX), SkScalarAve(q[0].fY, q[1].fY) }; 643e9709e831954c3427d5cb839e84221a177bfedebethannicholas 644e9709e831954c3427d5cb839e84221a177bfedebethannicholas pointsLeft >>= 1; 645e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_quadratic_points(p0, q[0], r, tolSqd, prev, head, pointsLeft, alloc); 646e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_quadratic_points(r, q[1], p2, tolSqd, prev, head, pointsLeft, alloc); 647e9709e831954c3427d5cb839e84221a177bfedebethannicholas return prev; 648e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 649e9709e831954c3427d5cb839e84221a177bfedebethannicholas 650e9709e831954c3427d5cb839e84221a177bfedebethannicholasVertex* generate_cubic_points(const SkPoint& p0, 651e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint& p1, 652e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint& p2, 653e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint& p3, 654e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar tolSqd, 655e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prev, 656e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex** head, 657e9709e831954c3427d5cb839e84221a177bfedebethannicholas int pointsLeft, 6585cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 659e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar d1 = p1.distanceToLineSegmentBetweenSqd(p0, p3); 660e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar d2 = p2.distanceToLineSegmentBetweenSqd(p0, p3); 661e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (pointsLeft < 2 || (d1 < tolSqd && d2 < tolSqd) || 662e9709e831954c3427d5cb839e84221a177bfedebethannicholas !SkScalarIsFinite(d1) || !SkScalarIsFinite(d2)) { 663e9709e831954c3427d5cb839e84221a177bfedebethannicholas return append_point_to_contour(p3, prev, head, alloc); 664e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 665e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint q[] = { 666e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(p0.fX, p1.fX), SkScalarAve(p0.fY, p1.fY) }, 667e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(p1.fX, p2.fX), SkScalarAve(p1.fY, p2.fY) }, 668e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(p2.fX, p3.fX), SkScalarAve(p2.fY, p3.fY) } 669e9709e831954c3427d5cb839e84221a177bfedebethannicholas }; 670e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint r[] = { 671e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(q[0].fX, q[1].fX), SkScalarAve(q[0].fY, q[1].fY) }, 672e9709e831954c3427d5cb839e84221a177bfedebethannicholas { SkScalarAve(q[1].fX, q[2].fX), SkScalarAve(q[1].fY, q[2].fY) } 673e9709e831954c3427d5cb839e84221a177bfedebethannicholas }; 674e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint s = { SkScalarAve(r[0].fX, r[1].fX), SkScalarAve(r[0].fY, r[1].fY) }; 675e9709e831954c3427d5cb839e84221a177bfedebethannicholas pointsLeft >>= 1; 676e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_cubic_points(p0, q[0], r[0], s, tolSqd, prev, head, pointsLeft, alloc); 677e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_cubic_points(s, r[1], q[2], p3, tolSqd, prev, head, pointsLeft, alloc); 678e9709e831954c3427d5cb839e84221a177bfedebethannicholas return prev; 679e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 680e9709e831954c3427d5cb839e84221a177bfedebethannicholas 681e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 1: convert the input path to a set of linear contours (linked list of Vertices). 682e9709e831954c3427d5cb839e84221a177bfedebethannicholas 683e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid path_to_contours(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, 6845cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Vertex** contours, SkArenaAlloc& alloc, bool *isLinear) { 685e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar toleranceSqd = tolerance * tolerance; 686e9709e831954c3427d5cb839e84221a177bfedebethannicholas 687e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint pts[4]; 688e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool done = false; 689e9709e831954c3427d5cb839e84221a177bfedebethannicholas *isLinear = true; 690e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPath::Iter iter(path, false); 691e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prev = nullptr; 692e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* head = nullptr; 693e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (path.isInverseFillType()) { 694e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint quad[4]; 695e9709e831954c3427d5cb839e84221a177bfedebethannicholas clipBounds.toQuad(quad); 6967ab96e92196dd74d5b95d33c8477b256813f3046senorblanco for (int i = 3; i >= 0; i--) { 697e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = append_point_to_contour(quad[i], prev, &head, alloc); 698e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 699e9709e831954c3427d5cb839e84221a177bfedebethannicholas head->fPrev = prev; 700e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = head; 701e9709e831954c3427d5cb839e84221a177bfedebethannicholas *contours++ = head; 702e9709e831954c3427d5cb839e84221a177bfedebethannicholas head = prev = nullptr; 703e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 704e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkAutoConicToQuads converter; 705e9709e831954c3427d5cb839e84221a177bfedebethannicholas while (!done) { 706e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPath::Verb verb = iter.next(pts); 707e9709e831954c3427d5cb839e84221a177bfedebethannicholas switch (verb) { 708e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kConic_Verb: { 709e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkScalar weight = iter.conicWeight(); 710e9709e831954c3427d5cb839e84221a177bfedebethannicholas const SkPoint* quadPts = converter.computeQuads(pts, weight, toleranceSqd); 711e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (int i = 0; i < converter.countQuads(); ++i) { 712e9709e831954c3427d5cb839e84221a177bfedebethannicholas int pointsLeft = GrPathUtils::quadraticPointCount(quadPts, tolerance); 713e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_quadratic_points(quadPts[0], quadPts[1], quadPts[2], 714e9709e831954c3427d5cb839e84221a177bfedebethannicholas toleranceSqd, prev, &head, pointsLeft, alloc); 715e9709e831954c3427d5cb839e84221a177bfedebethannicholas quadPts += 2; 716e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 717e9709e831954c3427d5cb839e84221a177bfedebethannicholas *isLinear = false; 718e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 719e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 720e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kMove_Verb: 721e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (head) { 722e9709e831954c3427d5cb839e84221a177bfedebethannicholas head->fPrev = prev; 723e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = head; 724e9709e831954c3427d5cb839e84221a177bfedebethannicholas *contours++ = head; 725e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 726e9709e831954c3427d5cb839e84221a177bfedebethannicholas head = prev = nullptr; 727e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = append_point_to_contour(pts[0], prev, &head, alloc); 728e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 729e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kLine_Verb: { 730e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = append_point_to_contour(pts[1], prev, &head, alloc); 731e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 732e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 733e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kQuad_Verb: { 734e9709e831954c3427d5cb839e84221a177bfedebethannicholas int pointsLeft = GrPathUtils::quadraticPointCount(pts, tolerance); 735e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_quadratic_points(pts[0], pts[1], pts[2], toleranceSqd, prev, 736e9709e831954c3427d5cb839e84221a177bfedebethannicholas &head, pointsLeft, alloc); 737e9709e831954c3427d5cb839e84221a177bfedebethannicholas *isLinear = false; 738e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 739e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 740e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kCubic_Verb: { 741e9709e831954c3427d5cb839e84221a177bfedebethannicholas int pointsLeft = GrPathUtils::cubicPointCount(pts, tolerance); 742e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = generate_cubic_points(pts[0], pts[1], pts[2], pts[3], 743e9709e831954c3427d5cb839e84221a177bfedebethannicholas toleranceSqd, prev, &head, pointsLeft, alloc); 744e9709e831954c3427d5cb839e84221a177bfedebethannicholas *isLinear = false; 745e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 746e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 747e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kClose_Verb: 748e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (head) { 749e9709e831954c3427d5cb839e84221a177bfedebethannicholas head->fPrev = prev; 750e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = head; 751e9709e831954c3427d5cb839e84221a177bfedebethannicholas *contours++ = head; 752e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 753e9709e831954c3427d5cb839e84221a177bfedebethannicholas head = prev = nullptr; 754e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 755e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kDone_Verb: 756e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (head) { 757e9709e831954c3427d5cb839e84221a177bfedebethannicholas head->fPrev = prev; 758e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = head; 759e9709e831954c3427d5cb839e84221a177bfedebethannicholas *contours++ = head; 760e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 761e9709e831954c3427d5cb839e84221a177bfedebethannicholas done = true; 762e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 763e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 764e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 765e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 766e9709e831954c3427d5cb839e84221a177bfedebethannicholas 767497890630b80a381a2ac4cbb9114b0320560bf8cStephen Whiteinline bool apply_fill_type(SkPath::FillType fillType, int winding) { 768e9709e831954c3427d5cb839e84221a177bfedebethannicholas switch (fillType) { 769e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kWinding_FillType: 770e9709e831954c3427d5cb839e84221a177bfedebethannicholas return winding != 0; 771e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kEvenOdd_FillType: 772e9709e831954c3427d5cb839e84221a177bfedebethannicholas return (winding & 1) != 0; 773e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kInverseWinding_FillType: 7747ab96e92196dd74d5b95d33c8477b256813f3046senorblanco return winding == 1; 775e9709e831954c3427d5cb839e84221a177bfedebethannicholas case SkPath::kInverseEvenOdd_FillType: 776e9709e831954c3427d5cb839e84221a177bfedebethannicholas return (winding & 1) == 1; 777e9709e831954c3427d5cb839e84221a177bfedebethannicholas default: 778e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(false); 779e9709e831954c3427d5cb839e84221a177bfedebethannicholas return false; 780e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 781e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 782e9709e831954c3427d5cb839e84221a177bfedebethannicholas 783497890630b80a381a2ac4cbb9114b0320560bf8cStephen Whiteinline bool apply_fill_type(SkPath::FillType fillType, Poly* poly) { 784497890630b80a381a2ac4cbb9114b0320560bf8cStephen White return poly && apply_fill_type(fillType, poly->fWinding); 785497890630b80a381a2ac4cbb9114b0320560bf8cStephen White} 786497890630b80a381a2ac4cbb9114b0320560bf8cStephen White 7875cdc9dda330db41d34e452a91b6b0995b5a57626Herb DerbyEdge* new_edge(Vertex* prev, Vertex* next, Edge::Type type, Comparator& c, SkArenaAlloc& alloc) { 7882f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White int winding = c.sweep_lt(prev->fPoint, next->fPoint) ? 1 : -1; 789e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* top = winding < 0 ? next : prev; 790e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* bottom = winding < 0 ? prev : next; 7915cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby return alloc.make<Edge>(top, bottom, winding, type); 792e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 793e9709e831954c3427d5cb839e84221a177bfedebethannicholas 794e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid remove_edge(Edge* edge, EdgeList* edges) { 795e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("removing edge %g -> %g\n", edge->fTop->fID, edge->fBottom->fID); 796f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkASSERT(edges->contains(edge)); 797f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco edges->remove(edge); 798e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 799e9709e831954c3427d5cb839e84221a177bfedebethannicholas 800e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid insert_edge(Edge* edge, Edge* prev, EdgeList* edges) { 801e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("inserting edge %g -> %g\n", edge->fTop->fID, edge->fBottom->fID); 802f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkASSERT(!edges->contains(edge)); 803e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next = prev ? prev->fRight : edges->fHead; 804f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco edges->insert(edge, prev, next); 805e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 806e9709e831954c3427d5cb839e84221a177bfedebethannicholas 807e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid find_enclosing_edges(Vertex* v, EdgeList* edges, Edge** left, Edge** right) { 808e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fFirstEdgeAbove) { 809e9709e831954c3427d5cb839e84221a177bfedebethannicholas *left = v->fFirstEdgeAbove->fLeft; 810e9709e831954c3427d5cb839e84221a177bfedebethannicholas *right = v->fLastEdgeAbove->fRight; 811e9709e831954c3427d5cb839e84221a177bfedebethannicholas return; 812e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 813e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next = nullptr; 814e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* prev; 815e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (prev = edges->fTail; prev != nullptr; prev = prev->fLeft) { 816e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (prev->isLeftOf(v)) { 817e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 818e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 819e9709e831954c3427d5cb839e84221a177bfedebethannicholas next = prev; 820e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 821e9709e831954c3427d5cb839e84221a177bfedebethannicholas *left = prev; 822e9709e831954c3427d5cb839e84221a177bfedebethannicholas *right = next; 823e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 824e9709e831954c3427d5cb839e84221a177bfedebethannicholas 825e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid find_enclosing_edges(Edge* edge, EdgeList* edges, Comparator& c, Edge** left, Edge** right) { 826e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* prev = nullptr; 827e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next; 828e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (next = edges->fHead; next != nullptr; next = next->fRight) { 829e9709e831954c3427d5cb839e84221a177bfedebethannicholas if ((c.sweep_gt(edge->fTop->fPoint, next->fTop->fPoint) && next->isRightOf(edge->fTop)) || 830e9709e831954c3427d5cb839e84221a177bfedebethannicholas (c.sweep_gt(next->fTop->fPoint, edge->fTop->fPoint) && edge->isLeftOf(next->fTop)) || 831e9709e831954c3427d5cb839e84221a177bfedebethannicholas (c.sweep_lt(edge->fBottom->fPoint, next->fBottom->fPoint) && 832e9709e831954c3427d5cb839e84221a177bfedebethannicholas next->isRightOf(edge->fBottom)) || 833e9709e831954c3427d5cb839e84221a177bfedebethannicholas (c.sweep_lt(next->fBottom->fPoint, edge->fBottom->fPoint) && 834e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->isLeftOf(next->fBottom))) { 835e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 836e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 837e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = next; 838e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 839e9709e831954c3427d5cb839e84221a177bfedebethannicholas *left = prev; 840e9709e831954c3427d5cb839e84221a177bfedebethannicholas *right = next; 841e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 842e9709e831954c3427d5cb839e84221a177bfedebethannicholas 843e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid fix_active_state(Edge* edge, EdgeList* activeEdges, Comparator& c) { 8442f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White if (!activeEdges) { 8452f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White return; 8462f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White } 8472f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White if (activeEdges->contains(edge)) { 848e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fBottom->fProcessed || !edge->fTop->fProcessed) { 849e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge(edge, activeEdges); 850e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 851e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (edge->fTop->fProcessed && !edge->fBottom->fProcessed) { 852e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* left; 853e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* right; 854e9709e831954c3427d5cb839e84221a177bfedebethannicholas find_enclosing_edges(edge, activeEdges, c, &left, &right); 855e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge(edge, left, activeEdges); 856e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 857e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 858e9709e831954c3427d5cb839e84221a177bfedebethannicholas 859e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid insert_edge_above(Edge* edge, Vertex* v, Comparator& c) { 860e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fTop->fPoint == edge->fBottom->fPoint || 861e9709e831954c3427d5cb839e84221a177bfedebethannicholas c.sweep_gt(edge->fTop->fPoint, edge->fBottom->fPoint)) { 862e9709e831954c3427d5cb839e84221a177bfedebethannicholas return; 863e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 864e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("insert edge (%g -> %g) above vertex %g\n", edge->fTop->fID, edge->fBottom->fID, v->fID); 865e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* prev = nullptr; 866e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next; 867e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (next = v->fFirstEdgeAbove; next; next = next->fNextEdgeAbove) { 868e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (next->isRightOf(edge->fTop)) { 869e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 870e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 871e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = next; 872e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 873e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco list_insert<Edge, &Edge::fPrevEdgeAbove, &Edge::fNextEdgeAbove>( 874e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge, prev, next, &v->fFirstEdgeAbove, &v->fLastEdgeAbove); 875e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 876e9709e831954c3427d5cb839e84221a177bfedebethannicholas 877e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid insert_edge_below(Edge* edge, Vertex* v, Comparator& c) { 878e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fTop->fPoint == edge->fBottom->fPoint || 879e9709e831954c3427d5cb839e84221a177bfedebethannicholas c.sweep_gt(edge->fTop->fPoint, edge->fBottom->fPoint)) { 880e9709e831954c3427d5cb839e84221a177bfedebethannicholas return; 881e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 882e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("insert edge (%g -> %g) below vertex %g\n", edge->fTop->fID, edge->fBottom->fID, v->fID); 883e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* prev = nullptr; 884e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next; 885e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (next = v->fFirstEdgeBelow; next; next = next->fNextEdgeBelow) { 886e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (next->isRightOf(edge->fBottom)) { 887e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 888e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 889e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = next; 890e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 891e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco list_insert<Edge, &Edge::fPrevEdgeBelow, &Edge::fNextEdgeBelow>( 892e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge, prev, next, &v->fFirstEdgeBelow, &v->fLastEdgeBelow); 893e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 894e9709e831954c3427d5cb839e84221a177bfedebethannicholas 895e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid remove_edge_above(Edge* edge) { 896e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("removing edge (%g -> %g) above vertex %g\n", edge->fTop->fID, edge->fBottom->fID, 897e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fBottom->fID); 898e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco list_remove<Edge, &Edge::fPrevEdgeAbove, &Edge::fNextEdgeAbove>( 899e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge, &edge->fBottom->fFirstEdgeAbove, &edge->fBottom->fLastEdgeAbove); 900e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 901e9709e831954c3427d5cb839e84221a177bfedebethannicholas 902e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid remove_edge_below(Edge* edge) { 903e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("removing edge (%g -> %g) below vertex %g\n", edge->fTop->fID, edge->fBottom->fID, 904e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fTop->fID); 905e6eaa320e8dac34396dc364aa0863574d7b5291csenorblanco list_remove<Edge, &Edge::fPrevEdgeBelow, &Edge::fNextEdgeBelow>( 906e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge, &edge->fTop->fFirstEdgeBelow, &edge->fTop->fLastEdgeBelow); 907e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 908e9709e831954c3427d5cb839e84221a177bfedebethannicholas 909e7a364d435843a868dcac2c61d78c34e5d3e326cStephen Whitevoid disconnect(Edge* edge) 910e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White{ 911e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge_above(edge); 912e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge_below(edge); 913e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White} 914e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White 915e7a364d435843a868dcac2c61d78c34e5d3e326cStephen Whitevoid erase_edge(Edge* edge, EdgeList* edges) { 916e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White LOG("erasing edge (%g -> %g)\n", edge->fTop->fID, edge->fBottom->fID); 917e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White disconnect(edge); 918f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (edges && edges->contains(edge)) { 919e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge(edge, edges); 920e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 921e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 922e9709e831954c3427d5cb839e84221a177bfedebethannicholas 923e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid merge_collinear_edges(Edge* edge, EdgeList* activeEdges, Comparator& c); 924e9709e831954c3427d5cb839e84221a177bfedebethannicholas 925e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid set_top(Edge* edge, Vertex* v, EdgeList* activeEdges, Comparator& c) { 926e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge_below(edge); 927e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fTop = v; 928e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->recompute(); 929e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge_below(edge, v, c); 930e9709e831954c3427d5cb839e84221a177bfedebethannicholas fix_active_state(edge, activeEdges, c); 931e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_collinear_edges(edge, activeEdges, c); 932e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 933e9709e831954c3427d5cb839e84221a177bfedebethannicholas 934e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid set_bottom(Edge* edge, Vertex* v, EdgeList* activeEdges, Comparator& c) { 935e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge_above(edge); 936e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fBottom = v; 937e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->recompute(); 938e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge_above(edge, v, c); 939e9709e831954c3427d5cb839e84221a177bfedebethannicholas fix_active_state(edge, activeEdges, c); 940e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_collinear_edges(edge, activeEdges, c); 941e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 942e9709e831954c3427d5cb839e84221a177bfedebethannicholas 943e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid merge_edges_above(Edge* edge, Edge* other, EdgeList* activeEdges, Comparator& c) { 944e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (coincident(edge->fTop->fPoint, other->fTop->fPoint)) { 945e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("merging coincident above edges (%g, %g) -> (%g, %g)\n", 946e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fTop->fPoint.fX, edge->fTop->fPoint.fY, 947e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fBottom->fPoint.fX, edge->fBottom->fPoint.fY); 948e9709e831954c3427d5cb839e84221a177bfedebethannicholas other->fWinding += edge->fWinding; 949e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White erase_edge(edge, activeEdges); 950e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(edge->fTop->fPoint, other->fTop->fPoint)) { 951e9709e831954c3427d5cb839e84221a177bfedebethannicholas other->fWinding += edge->fWinding; 952e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_bottom(edge, other->fTop, activeEdges, c); 953e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 954e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fWinding += other->fWinding; 955e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_bottom(other, edge->fTop, activeEdges, c); 956e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 957e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 958e9709e831954c3427d5cb839e84221a177bfedebethannicholas 959e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid merge_edges_below(Edge* edge, Edge* other, EdgeList* activeEdges, Comparator& c) { 960e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (coincident(edge->fBottom->fPoint, other->fBottom->fPoint)) { 961e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("merging coincident below edges (%g, %g) -> (%g, %g)\n", 962e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fTop->fPoint.fX, edge->fTop->fPoint.fY, 963e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fBottom->fPoint.fX, edge->fBottom->fPoint.fY); 964e9709e831954c3427d5cb839e84221a177bfedebethannicholas other->fWinding += edge->fWinding; 965e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White erase_edge(edge, activeEdges); 966e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(edge->fBottom->fPoint, other->fBottom->fPoint)) { 967e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fWinding += other->fWinding; 968e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_top(other, edge->fBottom, activeEdges, c); 969e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 970e9709e831954c3427d5cb839e84221a177bfedebethannicholas other->fWinding += edge->fWinding; 971e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_top(edge, other->fBottom, activeEdges, c); 972e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 973e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 974e9709e831954c3427d5cb839e84221a177bfedebethannicholas 975e9709e831954c3427d5cb839e84221a177bfedebethannicholasvoid merge_collinear_edges(Edge* edge, EdgeList* activeEdges, Comparator& c) { 976e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fPrevEdgeAbove && (edge->fTop == edge->fPrevEdgeAbove->fTop || 977e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->fPrevEdgeAbove->isLeftOf(edge->fTop))) { 978e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_edges_above(edge, edge->fPrevEdgeAbove, activeEdges, c); 979e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (edge->fNextEdgeAbove && (edge->fTop == edge->fNextEdgeAbove->fTop || 980e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->isLeftOf(edge->fNextEdgeAbove->fTop))) { 981e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_edges_above(edge, edge->fNextEdgeAbove, activeEdges, c); 982e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 983e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fPrevEdgeBelow && (edge->fBottom == edge->fPrevEdgeBelow->fBottom || 984e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->fPrevEdgeBelow->isLeftOf(edge->fBottom))) { 985e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_edges_below(edge, edge->fPrevEdgeBelow, activeEdges, c); 986e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (edge->fNextEdgeBelow && (edge->fBottom == edge->fNextEdgeBelow->fBottom || 987e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->isLeftOf(edge->fNextEdgeBelow->fBottom))) { 988e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_edges_below(edge, edge->fNextEdgeBelow, activeEdges, c); 989e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 990e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 991e9709e831954c3427d5cb839e84221a177bfedebethannicholas 9925cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid split_edge(Edge* edge, Vertex* v, EdgeList* activeEdges, Comparator& c, SkArenaAlloc& alloc); 993e9709e831954c3427d5cb839e84221a177bfedebethannicholas 9945cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid cleanup_active_edges(Edge* edge, EdgeList* activeEdges, Comparator& c, SkArenaAlloc& alloc) { 995e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* top = edge->fTop; 996e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* bottom = edge->fBottom; 997e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fLeft) { 998e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* leftTop = edge->fLeft->fTop; 999e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* leftBottom = edge->fLeft->fBottom; 1000e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (c.sweep_gt(top->fPoint, leftTop->fPoint) && !edge->fLeft->isLeftOf(top)) { 1001e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge->fLeft, edge->fTop, activeEdges, c, alloc); 1002e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_gt(leftTop->fPoint, top->fPoint) && !edge->isRightOf(leftTop)) { 1003e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, leftTop, activeEdges, c, alloc); 1004e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(bottom->fPoint, leftBottom->fPoint) && 1005e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->fLeft->isLeftOf(bottom)) { 1006e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge->fLeft, bottom, activeEdges, c, alloc); 1007e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(leftBottom->fPoint, bottom->fPoint) && !edge->isRightOf(leftBottom)) { 1008e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, leftBottom, activeEdges, c, alloc); 1009e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1010e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1011e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (edge->fRight) { 1012e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* rightTop = edge->fRight->fTop; 1013e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* rightBottom = edge->fRight->fBottom; 1014e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (c.sweep_gt(top->fPoint, rightTop->fPoint) && !edge->fRight->isRightOf(top)) { 1015e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge->fRight, top, activeEdges, c, alloc); 1016e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_gt(rightTop->fPoint, top->fPoint) && !edge->isLeftOf(rightTop)) { 1017e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, rightTop, activeEdges, c, alloc); 1018e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(bottom->fPoint, rightBottom->fPoint) && 1019e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->fRight->isRightOf(bottom)) { 1020e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge->fRight, bottom, activeEdges, c, alloc); 1021e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_lt(rightBottom->fPoint, bottom->fPoint) && 1022e9709e831954c3427d5cb839e84221a177bfedebethannicholas !edge->isLeftOf(rightBottom)) { 1023e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, rightBottom, activeEdges, c, alloc); 1024e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1025e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1026e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1027e9709e831954c3427d5cb839e84221a177bfedebethannicholas 10285cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid split_edge(Edge* edge, Vertex* v, EdgeList* activeEdges, Comparator& c, SkArenaAlloc& alloc) { 1029e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("splitting edge (%g -> %g) at vertex %g (%g, %g)\n", 1030e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge->fTop->fID, edge->fBottom->fID, 1031e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fID, v->fPoint.fX, v->fPoint.fY); 1032e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (c.sweep_lt(v->fPoint, edge->fTop->fPoint)) { 1033e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_top(edge, v, activeEdges, c); 1034e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (c.sweep_gt(v->fPoint, edge->fBottom->fPoint)) { 1035e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_bottom(edge, v, activeEdges, c); 1036e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 10375cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Edge* newEdge = alloc.make<Edge>(v, edge->fBottom, edge->fWinding, edge->fType); 1038e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge_below(newEdge, v, c); 1039e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge_above(newEdge, edge->fBottom, c); 1040e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_bottom(edge, v, activeEdges, c); 1041e9709e831954c3427d5cb839e84221a177bfedebethannicholas cleanup_active_edges(edge, activeEdges, c, alloc); 1042e9709e831954c3427d5cb839e84221a177bfedebethannicholas fix_active_state(newEdge, activeEdges, c); 1043e9709e831954c3427d5cb839e84221a177bfedebethannicholas merge_collinear_edges(newEdge, activeEdges, c); 1044e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1045e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1046e9709e831954c3427d5cb839e84221a177bfedebethannicholas 10475cdc9dda330db41d34e452a91b6b0995b5a57626Herb DerbyEdge* connect(Vertex* prev, Vertex* next, Edge::Type type, Comparator& c, SkArenaAlloc& alloc, 104848ded38da99c1171ba1bb469f6500f8214e9105cStephen White int winding_scale = 1) { 1049bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White Edge* edge = new_edge(prev, next, type, c, alloc); 10508a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White insert_edge_below(edge, edge->fTop, c); 10518a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White insert_edge_above(edge, edge->fBottom, c); 105248ded38da99c1171ba1bb469f6500f8214e9105cStephen White edge->fWinding *= winding_scale; 1053f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco merge_collinear_edges(edge, nullptr, c); 1054f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return edge; 1055f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1056f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1057bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen Whitevoid merge_vertices(Vertex* src, Vertex* dst, VertexList* mesh, Comparator& c, 10585cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 1059e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("found coincident verts at %g, %g; merging %g into %g\n", src->fPoint.fX, src->fPoint.fY, 1060e9709e831954c3427d5cb839e84221a177bfedebethannicholas src->fID, dst->fID); 1061f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco dst->fAlpha = SkTMax(src->fAlpha, dst->fAlpha); 1062e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* edge = src->fFirstEdgeAbove; edge;) { 1063e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next = edge->fNextEdgeAbove; 1064e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_bottom(edge, dst, nullptr, c); 1065e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge = next; 1066e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1067e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* edge = src->fFirstEdgeBelow; edge;) { 1068e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* next = edge->fNextEdgeBelow; 1069e9709e831954c3427d5cb839e84221a177bfedebethannicholas set_top(edge, dst, nullptr, c); 1070e9709e831954c3427d5cb839e84221a177bfedebethannicholas edge = next; 1071e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1072bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White mesh->remove(src); 1073e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1074e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1075f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancouint8_t max_edge_alpha(Edge* a, Edge* b) { 107656158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White if (a->fType == Edge::Type::kInner || b->fType == Edge::Type::kInner) { 10772f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White return 255; 10782f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White } else if (a->fType == Edge::Type::kOuter && b->fType == Edge::Type::kOuter) { 10792f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White return 0; 10802f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White } else { 10812f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White return SkTMax(SkTMax(a->fTop->fAlpha, a->fBottom->fAlpha), 10822f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White SkTMax(b->fTop->fAlpha, b->fBottom->fAlpha)); 10832f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White } 1084f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1085f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1086e9709e831954c3427d5cb839e84221a177bfedebethannicholasVertex* check_for_intersection(Edge* edge, Edge* other, EdgeList* activeEdges, Comparator& c, 10875cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 1088e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (!edge || !other) { 1089e9709e831954c3427d5cb839e84221a177bfedebethannicholas return nullptr; 1090e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 109156158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White SkPoint p; 109256158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White uint8_t alpha; 109356158ae600a73ac2e74f5a5862de0fab466b52b6Stephen White if (edge->intersect(*other, &p, &alpha)) { 1094e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* v; 1095e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("found intersection, pt is %g, %g\n", p.fX, p.fY); 1096e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (p == edge->fTop->fPoint || c.sweep_lt(p, edge->fTop->fPoint)) { 1097e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(other, edge->fTop, activeEdges, c, alloc); 1098e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = edge->fTop; 1099e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (p == edge->fBottom->fPoint || c.sweep_gt(p, edge->fBottom->fPoint)) { 1100e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(other, edge->fBottom, activeEdges, c, alloc); 1101e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = edge->fBottom; 1102e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (p == other->fTop->fPoint || c.sweep_lt(p, other->fTop->fPoint)) { 1103e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, other->fTop, activeEdges, c, alloc); 1104e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = other->fTop; 1105e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (p == other->fBottom->fPoint || c.sweep_gt(p, other->fBottom->fPoint)) { 1106e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, other->fBottom, activeEdges, c, alloc); 1107e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = other->fBottom; 1108e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1109e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* nextV = edge->fTop; 1110e9709e831954c3427d5cb839e84221a177bfedebethannicholas while (c.sweep_lt(p, nextV->fPoint)) { 1111e9709e831954c3427d5cb839e84221a177bfedebethannicholas nextV = nextV->fPrev; 1112e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1113e9709e831954c3427d5cb839e84221a177bfedebethannicholas while (c.sweep_lt(nextV->fPoint, p)) { 1114e9709e831954c3427d5cb839e84221a177bfedebethannicholas nextV = nextV->fNext; 1115e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1116e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prevV = nextV->fPrev; 1117e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (coincident(prevV->fPoint, p)) { 1118e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = prevV; 1119e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else if (coincident(nextV->fPoint, p)) { 1120e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = nextV; 1121e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 11225cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby v = alloc.make<Vertex>(p, alpha); 1123e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("inserting between %g (%g, %g) and %g (%g, %g)\n", 1124e9709e831954c3427d5cb839e84221a177bfedebethannicholas prevV->fID, prevV->fPoint.fX, prevV->fPoint.fY, 1125e9709e831954c3427d5cb839e84221a177bfedebethannicholas nextV->fID, nextV->fPoint.fX, nextV->fPoint.fY); 1126e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1127e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fID = (nextV->fID + prevV->fID) * 0.5f; 1128e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 1129e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPrev = prevV; 1130e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fNext = nextV; 1131e9709e831954c3427d5cb839e84221a177bfedebethannicholas prevV->fNext = v; 1132e9709e831954c3427d5cb839e84221a177bfedebethannicholas nextV->fPrev = v; 1133e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1134e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(edge, v, activeEdges, c, alloc); 1135e9709e831954c3427d5cb839e84221a177bfedebethannicholas split_edge(other, v, activeEdges, c, alloc); 1136e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 113792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White v->fAlpha = SkTMax(v->fAlpha, alpha); 1138e9709e831954c3427d5cb839e84221a177bfedebethannicholas return v; 1139e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1140e9709e831954c3427d5cb839e84221a177bfedebethannicholas return nullptr; 1141e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1142e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1143f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancovoid sanitize_contours(Vertex** contours, int contourCnt, bool approximate) { 1144e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (int i = 0; i < contourCnt; ++i) { 1145e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(contours[i]); 11465926f2da752d1bff0051fda4137bb967f9e91d5fStephen White if (approximate) { 11475926f2da752d1bff0051fda4137bb967f9e91d5fStephen White round(&contours[i]->fPrev->fPoint); 11485926f2da752d1bff0051fda4137bb967f9e91d5fStephen White } 1149e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Vertex* v = contours[i];;) { 1150f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (approximate) { 1151f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco round(&v->fPoint); 1152f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1153e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (coincident(v->fPrev->fPoint, v->fPoint)) { 1154e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("vertex %g,%g coincident; removing\n", v->fPoint.fX, v->fPoint.fY); 1155e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fPrev == v) { 1156e9709e831954c3427d5cb839e84221a177bfedebethannicholas contours[i] = nullptr; 1157e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 1158e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1159e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPrev->fNext = v->fNext; 1160e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fNext->fPrev = v->fPrev; 1161e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (contours[i] == v) { 11625926f2da752d1bff0051fda4137bb967f9e91d5fStephen White contours[i] = v->fPrev; 1163e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1164e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = v->fPrev; 1165e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1166e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = v->fNext; 1167e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v == contours[i]) break; 1168e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1169e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1170e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1171e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1172e9709e831954c3427d5cb839e84221a177bfedebethannicholas 11735cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid merge_coincident_vertices(VertexList* mesh, Comparator& c, SkArenaAlloc& alloc) { 1174bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White for (Vertex* v = mesh->fHead->fNext; v != nullptr; v = v->fNext) { 1175e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (c.sweep_lt(v->fPoint, v->fPrev->fPoint)) { 1176e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPoint = v->fPrev->fPoint; 1177e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1178e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (coincident(v->fPrev->fPoint, v->fPoint)) { 1179bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White merge_vertices(v->fPrev, v, mesh, c, alloc); 1180e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1181e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1182e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1183e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1184e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 2: convert the contours to a mesh of edges connecting the vertices. 1185e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1186bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen Whitevoid build_edges(Vertex** contours, int contourCnt, VertexList* mesh, Comparator& c, 11875cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 1188e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* prev = nullptr; 1189e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (int i = 0; i < contourCnt; ++i) { 1190e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Vertex* v = contours[i]; v != nullptr;) { 1191e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* vNext = v->fNext; 1192bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White connect(v->fPrev, v, Edge::Type::kInner, c, alloc); 1193e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (prev) { 1194e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev->fNext = v; 1195e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fPrev = prev; 1196e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1197bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White mesh->fHead = v; 1198e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1199e9709e831954c3427d5cb839e84221a177bfedebethannicholas prev = v; 1200e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = vNext; 1201e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v == contours[i]) break; 1202e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1203e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1204e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (prev) { 1205bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White prev->fNext = mesh->fHead->fPrev = nullptr; 1206e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1207bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White mesh->fTail = prev; 1208e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1209e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1210e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 3: sort the vertices by increasing sweep direction. 1211e9709e831954c3427d5cb839e84221a177bfedebethannicholas 121216a40cb65adeb4d94b84479f9946c360ed73e1bbStephen Whitetemplate <CompareFunc sweep_lt> 121316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen Whitevoid merge_sort(VertexList* vertices) { 121416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Vertex* slow = vertices->fHead; 121516a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White if (!slow) { 1216e9709e831954c3427d5cb839e84221a177bfedebethannicholas return; 1217e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 121816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Vertex* fast = slow->fNext; 121916a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White if (!fast) { 122016a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White return; 122116a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } 122216a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White do { 122316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White fast = fast->fNext; 122416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White if (fast) { 122516a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White fast = fast->fNext; 122616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White slow = slow->fNext; 122716a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } 122816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } while (fast); 122916a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White VertexList front(vertices->fHead, slow); 123016a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White VertexList back(slow->fNext, vertices->fTail); 123116a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White front.fTail->fNext = back.fHead->fPrev = nullptr; 1232e9709e831954c3427d5cb839e84221a177bfedebethannicholas 123316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White merge_sort<sweep_lt>(&front); 123416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White merge_sort<sweep_lt>(&back); 1235e9709e831954c3427d5cb839e84221a177bfedebethannicholas 123616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White vertices->fHead = vertices->fTail = nullptr; 123716a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Vertex* a = front.fHead; 123816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Vertex* b = back.fHead; 1239e9709e831954c3427d5cb839e84221a177bfedebethannicholas while (a && b) { 124016a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White if (sweep_lt(a->fPoint, b->fPoint)) { 1241e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* next = a->fNext; 124216a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White vertices->append(a); 1243e9709e831954c3427d5cb839e84221a177bfedebethannicholas a = next; 1244e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1245e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* next = b->fNext; 124616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White vertices->append(b); 1247e9709e831954c3427d5cb839e84221a177bfedebethannicholas b = next; 1248e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1249e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1250e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (a) { 125116a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White vertices->insert(a, vertices->fTail, a->fNext); 1252e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1253e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (b) { 125416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White vertices->insert(b, vertices->fTail, b->fNext); 1255e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1256e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1257e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1258e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 4: Simplify the mesh by inserting new vertices at intersecting edges. 1259e9709e831954c3427d5cb839e84221a177bfedebethannicholas 12605cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid simplify(const VertexList& vertices, Comparator& c, SkArenaAlloc& alloc) { 1261e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("simplifying complex polygons\n"); 1262e9709e831954c3427d5cb839e84221a177bfedebethannicholas EdgeList activeEdges; 1263bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White for (Vertex* v = vertices.fHead; v != nullptr; v = v->fNext) { 1264e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (!v->fFirstEdgeAbove && !v->fFirstEdgeBelow) { 1265e9709e831954c3427d5cb839e84221a177bfedebethannicholas continue; 1266e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1267e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1268f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco LOG("\nvertex %g: (%g,%g), alpha %d\n", v->fID, v->fPoint.fX, v->fPoint.fY, v->fAlpha); 1269e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 12708a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Edge* leftEnclosingEdge; 12718a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Edge* rightEnclosingEdge; 1272e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool restartChecks; 1273e9709e831954c3427d5cb839e84221a177bfedebethannicholas do { 1274e9709e831954c3427d5cb839e84221a177bfedebethannicholas restartChecks = false; 1275e9709e831954c3427d5cb839e84221a177bfedebethannicholas find_enclosing_edges(v, &activeEdges, &leftEnclosingEdge, &rightEnclosingEdge); 1276e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fFirstEdgeBelow) { 1277bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White for (Edge* edge = v->fFirstEdgeBelow; edge; edge = edge->fNextEdgeBelow) { 1278e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (check_for_intersection(edge, leftEnclosingEdge, &activeEdges, c, alloc)) { 1279e9709e831954c3427d5cb839e84221a177bfedebethannicholas restartChecks = true; 1280e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 1281e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1282e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (check_for_intersection(edge, rightEnclosingEdge, &activeEdges, c, alloc)) { 1283e9709e831954c3427d5cb839e84221a177bfedebethannicholas restartChecks = true; 1284e9709e831954c3427d5cb839e84221a177bfedebethannicholas break; 1285e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1286e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1287e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1288e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (Vertex* pv = check_for_intersection(leftEnclosingEdge, rightEnclosingEdge, 1289e9709e831954c3427d5cb839e84221a177bfedebethannicholas &activeEdges, c, alloc)) { 1290e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (c.sweep_lt(pv->fPoint, v->fPoint)) { 1291e9709e831954c3427d5cb839e84221a177bfedebethannicholas v = pv; 1292e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1293e9709e831954c3427d5cb839e84221a177bfedebethannicholas restartChecks = true; 1294e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1295e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1296e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1297e9709e831954c3427d5cb839e84221a177bfedebethannicholas } while (restartChecks); 1298f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (v->fAlpha == 0) { 129948ded38da99c1171ba1bb469f6500f8214e9105cStephen White if ((leftEnclosingEdge && leftEnclosingEdge->fWinding < 0) && 130048ded38da99c1171ba1bb469f6500f8214e9105cStephen White (rightEnclosingEdge && rightEnclosingEdge->fWinding > 0)) { 1301f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco v->fAlpha = max_edge_alpha(leftEnclosingEdge, rightEnclosingEdge); 1302f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1303f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1304e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = v->fFirstEdgeAbove; e; e = e->fNextEdgeAbove) { 1305e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge(e, &activeEdges); 1306e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1307e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* leftEdge = leftEnclosingEdge; 1308e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = v->fFirstEdgeBelow; e; e = e->fNextEdgeBelow) { 1309e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge(e, leftEdge, &activeEdges); 1310e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftEdge = e; 1311e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1312e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fProcessed = true; 1313e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1314e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1315e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1316e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 5: Tessellate the simplified mesh into monotone polygons. 1317e9709e831954c3427d5cb839e84221a177bfedebethannicholas 13185cdc9dda330db41d34e452a91b6b0995b5a57626Herb DerbyPoly* tessellate(const VertexList& vertices, SkArenaAlloc& alloc) { 1319e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("tessellating simple polygons\n"); 1320e9709e831954c3427d5cb839e84221a177bfedebethannicholas EdgeList activeEdges; 1321e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* polys = nullptr; 1322bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White for (Vertex* v = vertices.fHead; v != nullptr; v = v->fNext) { 1323e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (!v->fFirstEdgeAbove && !v->fFirstEdgeBelow) { 1324e9709e831954c3427d5cb839e84221a177bfedebethannicholas continue; 1325e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1326e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1327f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco LOG("\nvertex %g: (%g,%g), alpha %d\n", v->fID, v->fPoint.fX, v->fPoint.fY, v->fAlpha); 1328e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 13298a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Edge* leftEnclosingEdge; 13308a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Edge* rightEnclosingEdge; 1331e9709e831954c3427d5cb839e84221a177bfedebethannicholas find_enclosing_edges(v, &activeEdges, &leftEnclosingEdge, &rightEnclosingEdge); 13328a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Poly* leftPoly; 13338a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White Poly* rightPoly; 1334e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fFirstEdgeAbove) { 1335e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftPoly = v->fFirstEdgeAbove->fLeftPoly; 1336e9709e831954c3427d5cb839e84221a177bfedebethannicholas rightPoly = v->fLastEdgeAbove->fRightPoly; 1337e9709e831954c3427d5cb839e84221a177bfedebethannicholas } else { 1338e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftPoly = leftEnclosingEdge ? leftEnclosingEdge->fRightPoly : nullptr; 1339e9709e831954c3427d5cb839e84221a177bfedebethannicholas rightPoly = rightEnclosingEdge ? rightEnclosingEdge->fLeftPoly : nullptr; 1340e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1341e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1342e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("edges above:\n"); 1343e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = v->fFirstEdgeAbove; e; e = e->fNextEdgeAbove) { 1344e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("%g -> %g, lpoly %d, rpoly %d\n", e->fTop->fID, e->fBottom->fID, 1345e9709e831954c3427d5cb839e84221a177bfedebethannicholas e->fLeftPoly ? e->fLeftPoly->fID : -1, e->fRightPoly ? e->fRightPoly->fID : -1); 1346e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1347e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("edges below:\n"); 1348e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = v->fFirstEdgeBelow; e; e = e->fNextEdgeBelow) { 1349e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("%g -> %g, lpoly %d, rpoly %d\n", e->fTop->fID, e->fBottom->fID, 1350e9709e831954c3427d5cb839e84221a177bfedebethannicholas e->fLeftPoly ? e->fLeftPoly->fID : -1, e->fRightPoly ? e->fRightPoly->fID : -1); 1351e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1352e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 1353e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fFirstEdgeAbove) { 1354e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (leftPoly) { 1355531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco leftPoly = leftPoly->addEdge(v->fFirstEdgeAbove, Poly::kRight_Side, alloc); 1356e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1357e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (rightPoly) { 1358531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightPoly = rightPoly->addEdge(v->fLastEdgeAbove, Poly::kLeft_Side, alloc); 1359e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1360e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = v->fFirstEdgeAbove; e != v->fLastEdgeAbove; e = e->fNextEdgeAbove) { 1361e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* rightEdge = e->fNextEdgeAbove; 13628a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White SkASSERT(rightEdge->isRightOf(e->fTop)); 13638a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White remove_edge(e, &activeEdges); 13648a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White if (e->fRightPoly) { 13658a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White e->fRightPoly->addEdge(e, Poly::kLeft_Side, alloc); 1366e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 13678a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White if (rightEdge->fLeftPoly && rightEdge->fLeftPoly != e->fRightPoly) { 1368531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightEdge->fLeftPoly->addEdge(e, Poly::kRight_Side, alloc); 1369e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1370e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1371e9709e831954c3427d5cb839e84221a177bfedebethannicholas remove_edge(v->fLastEdgeAbove, &activeEdges); 1372e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (!v->fFirstEdgeBelow) { 1373e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (leftPoly && rightPoly && leftPoly != rightPoly) { 1374e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(leftPoly->fPartner == nullptr && rightPoly->fPartner == nullptr); 1375e9709e831954c3427d5cb839e84221a177bfedebethannicholas rightPoly->fPartner = leftPoly; 1376e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftPoly->fPartner = rightPoly; 1377e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1378e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1379e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1380e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (v->fFirstEdgeBelow) { 1381e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (!v->fFirstEdgeAbove) { 138293e3fff79eaaa86bc2fb740a42111a074ccc73absenorblanco if (leftPoly && rightPoly) { 1383531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco if (leftPoly == rightPoly) { 1384531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco if (leftPoly->fTail && leftPoly->fTail->fSide == Poly::kLeft_Side) { 1385531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco leftPoly = new_poly(&polys, leftPoly->lastVertex(), 1386531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco leftPoly->fWinding, alloc); 1387531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco leftEnclosingEdge->fRightPoly = leftPoly; 1388531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } else { 1389531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightPoly = new_poly(&polys, rightPoly->lastVertex(), 1390531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightPoly->fWinding, alloc); 1391531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightEnclosingEdge->fLeftPoly = rightPoly; 1392531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco } 1393e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 13945cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Edge* join = alloc.make<Edge>(leftPoly->lastVertex(), v, 1, Edge::Type::kInner); 1395531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco leftPoly = leftPoly->addEdge(join, Poly::kRight_Side, alloc); 1396531237ef3aaf0d3c86e0853fde3b4c8f517bc662senorblanco rightPoly = rightPoly->addEdge(join, Poly::kLeft_Side, alloc); 1397e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1398e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1399e9709e831954c3427d5cb839e84221a177bfedebethannicholas Edge* leftEdge = v->fFirstEdgeBelow; 1400e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftEdge->fLeftPoly = leftPoly; 1401e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge(leftEdge, leftEnclosingEdge, &activeEdges); 1402e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* rightEdge = leftEdge->fNextEdgeBelow; rightEdge; 1403e9709e831954c3427d5cb839e84221a177bfedebethannicholas rightEdge = rightEdge->fNextEdgeBelow) { 1404e9709e831954c3427d5cb839e84221a177bfedebethannicholas insert_edge(rightEdge, leftEdge, &activeEdges); 1405e9709e831954c3427d5cb839e84221a177bfedebethannicholas int winding = leftEdge->fLeftPoly ? leftEdge->fLeftPoly->fWinding : 0; 1406e9709e831954c3427d5cb839e84221a177bfedebethannicholas winding += leftEdge->fWinding; 1407e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (winding != 0) { 1408e9709e831954c3427d5cb839e84221a177bfedebethannicholas Poly* poly = new_poly(&polys, v, winding, alloc); 1409e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftEdge->fRightPoly = rightEdge->fLeftPoly = poly; 1410e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1411e9709e831954c3427d5cb839e84221a177bfedebethannicholas leftEdge = rightEdge; 1412e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1413e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fLastEdgeBelow->fRightPoly = rightPoly; 1414e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1415e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1416e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("\nactive edges:\n"); 1417e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Edge* e = activeEdges.fHead; e != nullptr; e = e->fRight) { 1418e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("%g -> %g, lpoly %d, rpoly %d\n", e->fTop->fID, e->fBottom->fID, 1419e9709e831954c3427d5cb839e84221a177bfedebethannicholas e->fLeftPoly ? e->fLeftPoly->fID : -1, e->fRightPoly ? e->fRightPoly->fID : -1); 1420e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1421e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 1422e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1423e9709e831954c3427d5cb839e84221a177bfedebethannicholas return polys; 1424e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1425e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1426bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen Whitevoid remove_non_boundary_edges(const VertexList& mesh, SkPath::FillType fillType, 14275cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 1428497890630b80a381a2ac4cbb9114b0320560bf8cStephen White LOG("removing non-boundary edges\n"); 1429497890630b80a381a2ac4cbb9114b0320560bf8cStephen White EdgeList activeEdges; 1430bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White for (Vertex* v = mesh.fHead; v != nullptr; v = v->fNext) { 1431497890630b80a381a2ac4cbb9114b0320560bf8cStephen White if (!v->fFirstEdgeAbove && !v->fFirstEdgeBelow) { 1432497890630b80a381a2ac4cbb9114b0320560bf8cStephen White continue; 1433497890630b80a381a2ac4cbb9114b0320560bf8cStephen White } 1434497890630b80a381a2ac4cbb9114b0320560bf8cStephen White Edge* leftEnclosingEdge; 1435497890630b80a381a2ac4cbb9114b0320560bf8cStephen White Edge* rightEnclosingEdge; 1436497890630b80a381a2ac4cbb9114b0320560bf8cStephen White find_enclosing_edges(v, &activeEdges, &leftEnclosingEdge, &rightEnclosingEdge); 1437497890630b80a381a2ac4cbb9114b0320560bf8cStephen White bool prevFilled = leftEnclosingEdge && 1438497890630b80a381a2ac4cbb9114b0320560bf8cStephen White apply_fill_type(fillType, leftEnclosingEdge->fWinding); 1439497890630b80a381a2ac4cbb9114b0320560bf8cStephen White for (Edge* e = v->fFirstEdgeAbove; e;) { 1440497890630b80a381a2ac4cbb9114b0320560bf8cStephen White Edge* next = e->fNextEdgeAbove; 1441497890630b80a381a2ac4cbb9114b0320560bf8cStephen White remove_edge(e, &activeEdges); 1442497890630b80a381a2ac4cbb9114b0320560bf8cStephen White bool filled = apply_fill_type(fillType, e->fWinding); 1443497890630b80a381a2ac4cbb9114b0320560bf8cStephen White if (filled == prevFilled) { 1444e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White disconnect(e); 1445f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1446497890630b80a381a2ac4cbb9114b0320560bf8cStephen White prevFilled = filled; 1447f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e = next; 1448f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1449497890630b80a381a2ac4cbb9114b0320560bf8cStephen White Edge* prev = leftEnclosingEdge; 1450497890630b80a381a2ac4cbb9114b0320560bf8cStephen White for (Edge* e = v->fFirstEdgeBelow; e; e = e->fNextEdgeBelow) { 1451497890630b80a381a2ac4cbb9114b0320560bf8cStephen White if (prev) { 1452497890630b80a381a2ac4cbb9114b0320560bf8cStephen White e->fWinding += prev->fWinding; 1453497890630b80a381a2ac4cbb9114b0320560bf8cStephen White } 1454497890630b80a381a2ac4cbb9114b0320560bf8cStephen White insert_edge(e, prev, &activeEdges); 1455497890630b80a381a2ac4cbb9114b0320560bf8cStephen White prev = e; 1456497890630b80a381a2ac4cbb9114b0320560bf8cStephen White } 1457682580fb204b72925a48d1d6fe8c9c30fa53bb67senorblanco } 1458f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1459f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1460f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancovoid get_edge_normal(const Edge* e, SkVector* normal) { 1461eaf0079d81beac9fea2da7a20c3587ebbbbe6463Stephen White normal->setNormalize(SkDoubleToScalar(e->fLine.fA) * e->fWinding, 1462eaf0079d81beac9fea2da7a20c3587ebbbbe6463Stephen White SkDoubleToScalar(e->fLine.fB) * e->fWinding); 1463f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1464f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1465f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// Stage 5c: detect and remove "pointy" vertices whose edge normals point in opposite directions 1466f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// and whose adjacent vertices are less than a quarter pixel from an edge. These are guaranteed to 1467f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// invert on stroking. 1468f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 14695cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid simplify_boundary(EdgeList* boundary, Comparator& c, SkArenaAlloc& alloc) { 1470f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Edge* prevEdge = boundary->fTail; 1471f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkVector prevNormal; 1472f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco get_edge_normal(prevEdge, &prevNormal); 1473f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco for (Edge* e = boundary->fHead; e != nullptr;) { 1474f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* prev = prevEdge->fWinding == 1 ? prevEdge->fTop : prevEdge->fBottom; 1475f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* next = e->fWinding == 1 ? e->fBottom : e->fTop; 1476f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco double dist = e->dist(prev->fPoint); 1477f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkVector normal; 1478f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco get_edge_normal(e, &normal); 1479eaf0079d81beac9fea2da7a20c3587ebbbbe6463Stephen White float denom = 0.0625f * static_cast<float>(e->fLine.magSq()); 1480f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (prevNormal.dot(normal) < 0.0 && (dist * dist) <= denom) { 1481bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White Edge* join = new_edge(prev, next, Edge::Type::kInner, c, alloc); 1482f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco insert_edge(join, e, boundary); 1483f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco remove_edge(prevEdge, boundary); 1484f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco remove_edge(e, boundary); 1485f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (join->fLeft && join->fRight) { 1486f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevEdge = join->fLeft; 1487f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e = join; 1488f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else { 1489f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevEdge = boundary->fTail; 1490f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e = boundary->fHead; // join->fLeft ? join->fLeft : join; 1491f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1492f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco get_edge_normal(prevEdge, &prevNormal); 1493f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else { 1494f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevEdge = e; 1495f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevNormal = normal; 1496f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e = e->fRight; 1497f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1498f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1499f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1500f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1501dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagnervoid fix_inversions(Vertex* prev, Vertex* next, Edge* prevBisector, Edge* nextBisector, 150292eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White Edge* prevEdge, Comparator& c) { 150392eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White if (!prev || !next) { 150492eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White return; 150592eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White } 150692eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White int winding = c.sweep_lt(prev->fPoint, next->fPoint) ? 1 : -1; 150792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White SkPoint p; 150892eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White uint8_t alpha; 1509dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner if (winding != prevEdge->fWinding && prevBisector->intersect(*nextBisector, &p, &alpha)) { 151092eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White prev->fPoint = next->fPoint = p; 151192eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White prev->fAlpha = next->fAlpha = alpha; 151292eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White } 151392eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White} 151492eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White 1515f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// Stage 5d: Displace edges by half a pixel inward and outward along their normals. Intersect to 1516f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// find new vertices, and set zero alpha on the exterior and one alpha on the interior. Build a 1517f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// new antialiased mesh from those vertices. 1518f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 15195cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid boundary_to_aa_mesh(EdgeList* boundary, VertexList* mesh, Comparator& c, SkArenaAlloc& alloc) { 15208a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White // A boundary with fewer than 3 edges is degenerate. 15218a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White if (!boundary->fHead || !boundary->fHead->fRight || !boundary->fHead->fRight->fRight) { 15228a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White return; 15238a0bfc5201f14c994fe8062ecf1ca34a172de9d3Stephen White } 1524f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Edge* prevEdge = boundary->fTail; 1525f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco float radius = 0.5f; 152649df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double offset = radius * sqrt(prevEdge->fLine.magSq()) * prevEdge->fWinding; 152749df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line prevInner(prevEdge->fTop, prevEdge->fBottom); 1528f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevInner.fC -= offset; 152949df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line prevOuter(prevEdge->fTop, prevEdge->fBottom); 1530f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevOuter.fC += offset; 1531f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco VertexList innerVertices; 1532f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco VertexList outerVertices; 1533dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner Edge* prevBisector = nullptr; 1534f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco for (Edge* e = boundary->fHead; e != nullptr; e = e->fRight) { 153549df8d17c56ee08ecf860289d501913d356f67dcsenorblanco double offset = radius * sqrt(e->fLine.magSq()) * e->fWinding; 153649df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line inner(e->fTop, e->fBottom); 1537f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco inner.fC -= offset; 153849df8d17c56ee08ecf860289d501913d356f67dcsenorblanco Line outer(e->fTop, e->fBottom); 1539f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco outer.fC += offset; 1540f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco SkPoint innerPoint, outerPoint; 154149df8d17c56ee08ecf860289d501913d356f67dcsenorblanco if (prevInner.intersect(inner, &innerPoint) && 154249df8d17c56ee08ecf860289d501913d356f67dcsenorblanco prevOuter.intersect(outer, &outerPoint)) { 15435cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Vertex* innerVertex = alloc.make<Vertex>(innerPoint, 255); 15445cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby Vertex* outerVertex = alloc.make<Vertex>(outerPoint, 0); 1545dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner Edge* bisector = new_edge(outerVertex, innerVertex, Edge::Type::kConnector, c, alloc); 154692eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White fix_inversions(innerVertices.fTail, innerVertex, prevBisector, bisector, prevEdge, c); 154792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White fix_inversions(outerVertices.fTail, outerVertex, prevBisector, bisector, prevEdge, c); 154892eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White innerVertices.append(innerVertex); 154992eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White outerVertices.append(outerVertex); 155092eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White prevBisector = bisector; 1551f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1552f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevInner = inner; 1553f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco prevOuter = outer; 155486cc841e23a81af69269de87224c57be274f40d1Stephen White prevEdge = e; 1555f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1556f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco innerVertices.close(); 1557f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco outerVertices.close(); 1558f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1559f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* innerVertex = innerVertices.fHead; 1560f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* outerVertex = outerVertices.fHead; 1561f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (!innerVertex || !outerVertex) { 1562f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return; 1563f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1564dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner Edge* bisector = new_edge(outerVertices.fHead, innerVertices.fHead, Edge::Type::kConnector, c, 1565dab4811661720e8f14675a09ca1a3b8f82e45680Ben Wagner alloc); 156692eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White fix_inversions(innerVertices.fTail, innerVertices.fHead, prevBisector, bisector, prevEdge, c); 156792eba8a5efc0860d4e95ba7f25052474a0bfca0cStephen White fix_inversions(outerVertices.fTail, outerVertices.fHead, prevBisector, bisector, prevEdge, c); 1568f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco do { 156948ded38da99c1171ba1bb469f6500f8214e9105cStephen White // Connect vertices into a quad mesh. Outer edges get default (1) winding. 157048ded38da99c1171ba1bb469f6500f8214e9105cStephen White // Inner edges get -2 winding. This ensures that the interior is always filled 157148ded38da99c1171ba1bb469f6500f8214e9105cStephen White // (-1 winding number for normal cases, 3 for thin features where the interior inverts). 157248ded38da99c1171ba1bb469f6500f8214e9105cStephen White // Connector edges get zero winding, since they're only structural (i.e., to ensure 157348ded38da99c1171ba1bb469f6500f8214e9105cStephen White // no 0-0-0 alpha triangles are produced), and shouldn't affect the poly winding number. 1574bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White connect(outerVertex->fPrev, outerVertex, Edge::Type::kOuter, c, alloc); 157548ded38da99c1171ba1bb469f6500f8214e9105cStephen White connect(innerVertex->fPrev, innerVertex, Edge::Type::kInner, c, alloc, -2); 157648ded38da99c1171ba1bb469f6500f8214e9105cStephen White connect(outerVertex, innerVertex, Edge::Type::kConnector, c, alloc, 0); 1577f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* innerNext = innerVertex->fNext; 1578f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Vertex* outerNext = outerVertex->fNext; 1579f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco mesh->append(innerVertex); 1580f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco mesh->append(outerVertex); 1581f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco innerVertex = innerNext; 1582f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco outerVertex = outerNext; 1583f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } while (innerVertex != innerVertices.fHead && outerVertex != outerVertices.fHead); 1584f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1585f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 15865cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid extract_boundary(EdgeList* boundary, Edge* e, SkPath::FillType fillType, SkArenaAlloc& alloc) { 1587497890630b80a381a2ac4cbb9114b0320560bf8cStephen White bool down = apply_fill_type(fillType, e->fWinding); 1588f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco while (e) { 1589f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e->fWinding = down ? 1 : -1; 1590f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Edge* next; 1591f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco boundary->append(e); 1592f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (down) { 1593f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco // Find outgoing edge, in clockwise order. 1594f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if ((next = e->fNextEdgeAbove)) { 1595f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = false; 1596f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else if ((next = e->fBottom->fLastEdgeBelow)) { 1597f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = true; 1598f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else if ((next = e->fPrevEdgeAbove)) { 1599f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = false; 1600f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1601f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else { 1602f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco // Find outgoing edge, in counter-clockwise order. 1603f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if ((next = e->fPrevEdgeBelow)) { 1604f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = true; 1605f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else if ((next = e->fTop->fFirstEdgeAbove)) { 1606f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = false; 1607f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } else if ((next = e->fNextEdgeBelow)) { 1608f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco down = true; 1609f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1610f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1611e7a364d435843a868dcac2c61d78c34e5d3e326cStephen White disconnect(e); 1612f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco e = next; 1613f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1614f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1615f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 16165ad721e94682b51b9f773d95704f11990468fef6Stephen White// Stage 5b: Extract boundaries from mesh, simplify and stroke them into a new mesh. 1617f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 16185ad721e94682b51b9f773d95704f11990468fef6Stephen Whitevoid extract_boundaries(const VertexList& inMesh, VertexList* outMesh, SkPath::FillType fillType, 16195ad721e94682b51b9f773d95704f11990468fef6Stephen White Comparator& c, SkArenaAlloc& alloc) { 16205ad721e94682b51b9f773d95704f11990468fef6Stephen White remove_non_boundary_edges(inMesh, fillType, alloc); 16215ad721e94682b51b9f773d95704f11990468fef6Stephen White for (Vertex* v = inMesh.fHead; v; v = v->fNext) { 1622f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco while (v->fFirstEdgeBelow) { 16235ad721e94682b51b9f773d95704f11990468fef6Stephen White EdgeList boundary; 16245ad721e94682b51b9f773d95704f11990468fef6Stephen White extract_boundary(&boundary, v->fFirstEdgeBelow, fillType, alloc); 16255ad721e94682b51b9f773d95704f11990468fef6Stephen White simplify_boundary(&boundary, c, alloc); 16265ad721e94682b51b9f773d95704f11990468fef6Stephen White boundary_to_aa_mesh(&boundary, outMesh, c, alloc); 1627f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1628f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1629f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1630f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1631f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// This is a driver function which calls stages 2-5 in turn. 1632f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1633bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen Whitevoid contours_to_mesh(Vertex** contours, int contourCnt, bool antialias, 16345cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby VertexList* mesh, Comparator& c, SkArenaAlloc& alloc) { 1635e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 1636e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (int i = 0; i < contourCnt; ++i) { 1637e9709e831954c3427d5cb839e84221a177bfedebethannicholas Vertex* v = contours[i]; 1638e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(v); 1639e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("path.moveTo(%20.20g, %20.20g);\n", v->fPoint.fX, v->fPoint.fY); 1640e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (v = v->fNext; v != contours[i]; v = v->fNext) { 1641e9709e831954c3427d5cb839e84221a177bfedebethannicholas LOG("path.lineTo(%20.20g, %20.20g);\n", v->fPoint.fX, v->fPoint.fY); 1642e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1643e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1644e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 1645f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco sanitize_contours(contours, contourCnt, antialias); 1646bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White build_edges(contours, contourCnt, mesh, c, alloc); 1647f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1648f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 16495cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derbyvoid sort_and_simplify(VertexList* vertices, Comparator& c, SkArenaAlloc& alloc) { 1650bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White if (!vertices || !vertices->fHead) { 16512f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White return; 1652e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1653e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1654e9709e831954c3427d5cb839e84221a177bfedebethannicholas // Sort vertices in Y (secondarily in X). 165516a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White if (c.fDirection == Comparator::Direction::kHorizontal) { 165616a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White merge_sort<sweep_lt_horiz>(vertices); 165716a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } else { 165816a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White merge_sort<sweep_lt_vert>(vertices); 165916a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White } 1660f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco merge_coincident_vertices(vertices, c, alloc); 1661e9709e831954c3427d5cb839e84221a177bfedebethannicholas#if LOGGING_ENABLED 16622e2cb9bc768bd13e1beeafc9acf8b8f19bea3215Stephen White for (Vertex* v = vertices->fHead; v != nullptr; v = v->fNext) { 1663e9709e831954c3427d5cb839e84221a177bfedebethannicholas static float gID = 0.0f; 1664e9709e831954c3427d5cb839e84221a177bfedebethannicholas v->fID = gID++; 1665e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1666e9709e831954c3427d5cb839e84221a177bfedebethannicholas#endif 1667f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco simplify(*vertices, c, alloc); 16682f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White} 16692f4686fa25ef7a14961f68be18e63de3567d0a15Stephen White 1670f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancoPoly* contours_to_polys(Vertex** contours, int contourCnt, SkPath::FillType fillType, 1671f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco const SkRect& pathBounds, bool antialias, 16725cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby SkArenaAlloc& alloc) { 167316a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White Comparator c(pathBounds.width() > pathBounds.height() ? Comparator::Direction::kHorizontal 167416a40cb65adeb4d94b84479f9946c360ed73e1bbStephen White : Comparator::Direction::kVertical); 1675bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White VertexList mesh; 1676bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White contours_to_mesh(contours, contourCnt, antialias, &mesh, c, alloc); 1677497890630b80a381a2ac4cbb9114b0320560bf8cStephen White sort_and_simplify(&mesh, c, alloc); 1678f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (antialias) { 1679f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco VertexList aaMesh; 16805ad721e94682b51b9f773d95704f11990468fef6Stephen White extract_boundaries(mesh, &aaMesh, fillType, c, alloc); 1681bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White sort_and_simplify(&aaMesh, c, alloc); 1682bf6137e08b703abd98b3e4d938e1cccef2350f4eStephen White return tessellate(aaMesh, alloc); 1683497890630b80a381a2ac4cbb9114b0320560bf8cStephen White } else { 1684497890630b80a381a2ac4cbb9114b0320560bf8cStephen White return tessellate(mesh, alloc); 1685f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1686f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco} 1687f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1688f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco// Stage 6: Triangulate the monotone polygons into a vertex buffer. 1689f57372daf0562a187c24d427366ac6d0cb980c9bsenorblancovoid* polys_to_triangles(Poly* polys, SkPath::FillType fillType, const AAParams* aaParams, 1690f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void* data) { 1691f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco for (Poly* poly = polys; poly; poly = poly->fNext) { 1692f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (apply_fill_type(fillType, poly)) { 1693f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco data = poly->emit(aaParams, data); 1694f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1695f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco } 1696f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return data; 1697e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1698e9709e831954c3427d5cb839e84221a177bfedebethannicholas 16999d524f22bfde5dc3dc8f48e1be39bdebd3bb0304halcanaryPoly* path_to_polys(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, 17005cdc9dda330db41d34e452a91b6b0995b5a57626Herb Derby int contourCnt, SkArenaAlloc& alloc, bool antialias, bool* isLinear) { 1701e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPath::FillType fillType = path.getFillType(); 1702e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (SkPath::IsInverseFillType(fillType)) { 1703e9709e831954c3427d5cb839e84221a177bfedebethannicholas contourCnt++; 1704e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 17057ecc59610de72043e9b7ebaf1ef45c43425e54fcBen Wagner std::unique_ptr<Vertex*[]> contours(new Vertex* [contourCnt]); 1706e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1707e9709e831954c3427d5cb839e84221a177bfedebethannicholas path_to_contours(path, tolerance, clipBounds, contours.get(), alloc, isLinear); 1708f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco return contours_to_polys(contours.get(), contourCnt, path.getFillType(), path.getBounds(), 1709f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco antialias, alloc); 1710e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1711e9709e831954c3427d5cb839e84221a177bfedebethannicholas 171211f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen Whiteint get_contour_count(const SkPath& path, SkScalar tolerance) { 171311f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White int contourCnt; 171411f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White int maxPts = GrPathUtils::worstCasePointCount(path, &contourCnt, tolerance); 1715e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (maxPts <= 0) { 171611f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White return 0; 1717e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1718e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (maxPts > ((int)SK_MaxU16 + 1)) { 1719e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkDebugf("Path not rendered, too many verts (%d)\n", maxPts); 172011f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White return 0; 1721e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 172211f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White return contourCnt; 1723e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1724e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1725e9709e831954c3427d5cb839e84221a177bfedebethannicholasint count_points(Poly* polys, SkPath::FillType fillType) { 1726e9709e831954c3427d5cb839e84221a177bfedebethannicholas int count = 0; 1727e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Poly* poly = polys; poly; poly = poly->fNext) { 1728f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (apply_fill_type(fillType, poly) && poly->fCount >= 3) { 1729e9709e831954c3427d5cb839e84221a177bfedebethannicholas count += (poly->fCount - 2) * (TESSELLATOR_WIREFRAME ? 6 : 3); 1730e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1731e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1732e9709e831954c3427d5cb839e84221a177bfedebethannicholas return count; 1733e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1734e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1735e9709e831954c3427d5cb839e84221a177bfedebethannicholas} // namespace 1736e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1737e9709e831954c3427d5cb839e84221a177bfedebethannicholasnamespace GrTessellator { 1738e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1739e9709e831954c3427d5cb839e84221a177bfedebethannicholas// Stage 6: Triangulate the monotone polygons into a vertex buffer. 1740e9709e831954c3427d5cb839e84221a177bfedebethannicholas 17419d524f22bfde5dc3dc8f48e1be39bdebd3bb0304halcanaryint PathToTriangles(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, 1742f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco VertexAllocator* vertexAllocator, bool antialias, const GrColor& color, 1743f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco bool canTweakAlphaForCoverage, bool* isLinear) { 174411f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White int contourCnt = get_contour_count(path, tolerance); 1745e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (contourCnt <= 0) { 1746e9709e831954c3427d5cb839e84221a177bfedebethannicholas *isLinear = true; 1747e9709e831954c3427d5cb839e84221a177bfedebethannicholas return 0; 1748e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 174911f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White SkArenaAlloc alloc(kArenaChunkSize); 1750f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Poly* polys = path_to_polys(path, tolerance, clipBounds, contourCnt, alloc, antialias, 1751f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco isLinear); 17527ab96e92196dd74d5b95d33c8477b256813f3046senorblanco SkPath::FillType fillType = antialias ? SkPath::kWinding_FillType : path.getFillType(); 1753e9709e831954c3427d5cb839e84221a177bfedebethannicholas int count = count_points(polys, fillType); 1754e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (0 == count) { 1755e9709e831954c3427d5cb839e84221a177bfedebethannicholas return 0; 1756e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1757e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1758f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void* verts = vertexAllocator->lock(count); 17596599efffeef3168dfc68dca99c30454c5c23b859senorblanco if (!verts) { 1760e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkDebugf("Could not allocate vertices\n"); 1761e9709e831954c3427d5cb839e84221a177bfedebethannicholas return 0; 1762e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1763f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1764f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco LOG("emitting %d verts\n", count); 1765f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco AAParams aaParams; 1766f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco aaParams.fTweakAlpha = canTweakAlphaForCoverage; 1767f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco aaParams.fColor = color; 1768f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco 1769f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco void* end = polys_to_triangles(polys, fillType, antialias ? &aaParams : nullptr, verts); 1770f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco int actualCount = static_cast<int>((static_cast<uint8_t*>(end) - static_cast<uint8_t*>(verts)) 1771f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco / vertexAllocator->stride()); 1772e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(actualCount <= count); 17736599efffeef3168dfc68dca99c30454c5c23b859senorblanco vertexAllocator->unlock(actualCount); 1774e9709e831954c3427d5cb839e84221a177bfedebethannicholas return actualCount; 1775e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1776e9709e831954c3427d5cb839e84221a177bfedebethannicholas 17779d524f22bfde5dc3dc8f48e1be39bdebd3bb0304halcanaryint PathToVertices(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, 1778e9709e831954c3427d5cb839e84221a177bfedebethannicholas GrTessellator::WindingVertex** verts) { 177911f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White int contourCnt = get_contour_count(path, tolerance); 1780e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (contourCnt <= 0) { 1781e9709e831954c3427d5cb839e84221a177bfedebethannicholas return 0; 1782e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 178311f65e0bb44f33b18e8bbb792d4f904ce1da0d5bStephen White SkArenaAlloc alloc(kArenaChunkSize); 1784e9709e831954c3427d5cb839e84221a177bfedebethannicholas bool isLinear; 1785f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco Poly* polys = path_to_polys(path, tolerance, clipBounds, contourCnt, alloc, false, &isLinear); 1786e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPath::FillType fillType = path.getFillType(); 1787e9709e831954c3427d5cb839e84221a177bfedebethannicholas int count = count_points(polys, fillType); 1788e9709e831954c3427d5cb839e84221a177bfedebethannicholas if (0 == count) { 1789e9709e831954c3427d5cb839e84221a177bfedebethannicholas *verts = nullptr; 1790e9709e831954c3427d5cb839e84221a177bfedebethannicholas return 0; 1791e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1792e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1793e9709e831954c3427d5cb839e84221a177bfedebethannicholas *verts = new GrTessellator::WindingVertex[count]; 1794e9709e831954c3427d5cb839e84221a177bfedebethannicholas GrTessellator::WindingVertex* vertsEnd = *verts; 1795e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint* points = new SkPoint[count]; 1796e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint* pointsEnd = points; 1797e9709e831954c3427d5cb839e84221a177bfedebethannicholas for (Poly* poly = polys; poly; poly = poly->fNext) { 1798f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco if (apply_fill_type(fillType, poly)) { 1799e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkPoint* start = pointsEnd; 1800f57372daf0562a187c24d427366ac6d0cb980c9bsenorblanco pointsEnd = static_cast<SkPoint*>(poly->emit(nullptr, pointsEnd)); 1801e9709e831954c3427d5cb839e84221a177bfedebethannicholas while (start != pointsEnd) { 1802e9709e831954c3427d5cb839e84221a177bfedebethannicholas vertsEnd->fPos = *start; 1803e9709e831954c3427d5cb839e84221a177bfedebethannicholas vertsEnd->fWinding = poly->fWinding; 1804e9709e831954c3427d5cb839e84221a177bfedebethannicholas ++start; 1805e9709e831954c3427d5cb839e84221a177bfedebethannicholas ++vertsEnd; 1806e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1807e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1808e9709e831954c3427d5cb839e84221a177bfedebethannicholas } 1809e9709e831954c3427d5cb839e84221a177bfedebethannicholas int actualCount = static_cast<int>(vertsEnd - *verts); 1810e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(actualCount <= count); 1811e9709e831954c3427d5cb839e84221a177bfedebethannicholas SkASSERT(pointsEnd - points == actualCount); 1812e9709e831954c3427d5cb839e84221a177bfedebethannicholas delete[] points; 1813e9709e831954c3427d5cb839e84221a177bfedebethannicholas return actualCount; 1814e9709e831954c3427d5cb839e84221a177bfedebethannicholas} 1815e9709e831954c3427d5cb839e84221a177bfedebethannicholas 1816e9709e831954c3427d5cb839e84221a177bfedebethannicholas} // namespace 1817