1f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 2f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Mesa 3-D graphics library 3f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Version: 6.5.3 4f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 5f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. 6f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 7f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Permission is hereby granted, free of charge, to any person obtaining a 8f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * copy of this software and associated documentation files (the "Software"), 9f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * to deal in the Software without restriction, including without limitation 10f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * and/or sell copies of the Software, and to permit persons to whom the 12f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Software is furnished to do so, subject to the following conditions: 13f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 14f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * The above copyright notice and this permission notice shall be included 15f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * in all copies or substantial portions of the Software. 16f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 17f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 21f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 22f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 24f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 25f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 26f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 27f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Antialiased Triangle rasterizers 28f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 29f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 30f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 31f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/glheader.h" 32f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/context.h" 33f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/colormac.h" 34f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/macros.h" 35f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/imports.h" 36f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "main/state.h" 37f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "s_aatriangle.h" 38f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "s_context.h" 39f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "s_span.h" 40f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 41f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 42f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 43f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Compute coefficients of a plane using the X,Y coords of the v0, v1, v2 44f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * vertices and the given Z values. 45f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * A point (x,y,z) lies on plane iff a*x+b*y+c*z+d = 0. 46f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 47f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline void 48f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgcompute_plane(const GLfloat v0[], const GLfloat v1[], const GLfloat v2[], 49f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org GLfloat z0, GLfloat z1, GLfloat z2, GLfloat plane[4]) 50f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 51f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat px = v1[0] - v0[0]; 52f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat py = v1[1] - v0[1]; 53f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat pz = z1 - z0; 54f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 55f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat qx = v2[0] - v0[0]; 56f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat qy = v2[1] - v0[1]; 57f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat qz = z2 - z0; 58f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 59f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* Crossproduct "(a,b,c):= dv1 x dv2" is orthogonal to plane. */ 60f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat a = py * qz - pz * qy; 61f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat b = pz * qx - px * qz; 62f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat c = px * qy - py * qx; 63f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* Point on the plane = "r*(a,b,c) + w", with fixed "r" depending 64f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org on the distance of plane from origin and arbitrary "w" parallel 65f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org to the plane. */ 66f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* The scalar product "(r*(a,b,c)+w)*(a,b,c)" is "r*(a^2+b^2+c^2)", 67f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org which is equal to "-d" below. */ 68f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat d = -(a * v0[0] + b * v0[1] + c * z0); 69f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 70f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[0] = a; 71f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[1] = b; 72f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[2] = c; 73f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[3] = d; 74f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 75f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 76f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 77f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 78f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Compute coefficients of a plane with a constant Z value. 79f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 80f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline void 81f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgconstant_plane(GLfloat value, GLfloat plane[4]) 82f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 83f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[0] = 0.0; 84f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[1] = 0.0; 85f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[2] = -1.0; 86f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org plane[3] = value; 87f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 88f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 89f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define CONSTANT_PLANE(VALUE, PLANE) \ 90f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgdo { \ 91f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org PLANE[0] = 0.0F; \ 92f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org PLANE[1] = 0.0F; \ 93f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org PLANE[2] = -1.0F; \ 94f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org PLANE[3] = VALUE; \ 95f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} while (0) 96f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 97f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 98f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 99f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 100f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Solve plane equation for Z at (X,Y). 101f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 102f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline GLfloat 103f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgsolve_plane(GLfloat x, GLfloat y, const GLfloat plane[4]) 104f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 105f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org ASSERT(plane[2] != 0.0F); 106f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return (plane[3] + plane[0] * x + plane[1] * y) / -plane[2]; 107f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 108f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 109f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 110f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define SOLVE_PLANE(X, Y, PLANE) \ 111f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org ((PLANE[3] + PLANE[0] * (X) + PLANE[1] * (Y)) / -PLANE[2]) 112f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 113f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 114f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 115f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Return 1 / solve_plane(). 116f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 117f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline GLfloat 118f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgsolve_plane_recip(GLfloat x, GLfloat y, const GLfloat plane[4]) 119f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 120f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat denom = plane[3] + plane[0] * x + plane[1] * y; 121f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (denom == 0.0F) 122f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return 0.0F; 123f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else 124f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return -plane[2] / denom; 125f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 126f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 127f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 128f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 129f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Solve plane and return clamped GLchan value. 130f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 131f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline GLchan 132f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgsolve_plane_chan(GLfloat x, GLfloat y, const GLfloat plane[4]) 133f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 134f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2]; 135f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#if CHAN_TYPE == GL_FLOAT 136f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return CLAMP(z, 0.0F, CHAN_MAXF); 137f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#else 138f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (z < 0) 139f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return 0; 140f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else if (z > CHAN_MAX) 141f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return CHAN_MAX; 142f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return (GLchan) IROUND_POS(z); 143f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#endif 144f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 145f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 146f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 147f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline GLfloat 148f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgplane_dx(const GLfloat plane[4]) 149f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 150f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return -plane[0] / plane[2]; 151f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 152f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 153f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic inline GLfloat 154f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgplane_dy(const GLfloat plane[4]) 155f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 156f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return -plane[1] / plane[2]; 157f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 158f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 159f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 160f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 161f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 162f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Compute how much (area) of the given pixel is inside the triangle. 163f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Vertices MUST be specified in counter-clockwise order. 164f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Return: coverage in [0, 1]. 165f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 166f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic GLfloat 167f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgcompute_coveragef(const GLfloat v0[3], const GLfloat v1[3], 168f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat v2[3], GLint winx, GLint winy) 169f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 170f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* Given a position [0,3]x[0,3] return the sub-pixel sample position. 171f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Contributed by Ray Tice. 172f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 173f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Jitter sample positions - 174f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * - average should be .5 in x & y for each column 175f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * - each of the 16 rows and columns should be used once 176f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * - the rectangle formed by the first four points 177f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * should contain the other points 178f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * - the distrubition should be fairly even in any given direction 179f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * 180f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * The pattern drawn below isn't optimal, but it's better than a regular 181f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * grid. In the drawing, the center of each subpixel is surrounded by 182f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * four dots. The "x" marks the jittered position relative to the 183f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * subpixel center. 184f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 185f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define POS(a, b) (0.5+a*4+b)/16 186f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org static const GLfloat samples[16][2] = { 187f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* start with the four corners */ 188f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(0, 2), POS(0, 0) }, 189f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(3, 3), POS(0, 2) }, 190f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(0, 0), POS(3, 1) }, 191f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(3, 1), POS(3, 3) }, 192f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* continue with interior samples */ 193f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(1, 1), POS(0, 1) }, 194f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(2, 0), POS(0, 3) }, 195f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(0, 3), POS(1, 3) }, 196f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(1, 2), POS(1, 0) }, 197f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(2, 3), POS(1, 2) }, 198f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(3, 2), POS(1, 1) }, 199f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(0, 1), POS(2, 2) }, 200f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(1, 0), POS(2, 1) }, 201f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(2, 1), POS(2, 3) }, 202f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(3, 0), POS(2, 0) }, 203f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(1, 3), POS(3, 0) }, 204f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org { POS(2, 2), POS(3, 2) } 205f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org }; 206f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 207f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat x = (GLfloat) winx; 208f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat y = (GLfloat) winy; 209f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dx0 = v1[0] - v0[0]; 210f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dy0 = v1[1] - v0[1]; 211f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dx1 = v2[0] - v1[0]; 212f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dy1 = v2[1] - v1[1]; 213f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dx2 = v0[0] - v2[0]; 214f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat dy2 = v0[1] - v2[1]; 215f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org GLint stop = 4, i; 216f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org GLfloat insideCount = 16.0F; 217f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 218f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org ASSERT(dx0 * dy1 - dx1 * dy0 >= 0.0); /* area >= 0.0 */ 219f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 220f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org for (i = 0; i < stop; i++) { 221f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat sx = x + samples[i][0]; 222f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const GLfloat sy = y + samples[i][1]; 223f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* cross product determines if sample is inside or outside each edge */ 224f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org GLfloat cross = (dx0 * (sy - v0[1]) - dy0 * (sx - v0[0])); 225f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* Check if the sample is exactly on an edge. If so, let cross be a 226f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * positive or negative value depending on the direction of the edge. 227f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 228f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross == 0.0F) 229f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org cross = dx0 + dy0; 230f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross < 0.0F) { 231f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* sample point is outside first edge */ 232f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org insideCount -= 1.0F; 233f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org stop = 16; 234f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 235f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else { 236f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* sample point is inside first edge */ 237f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org cross = (dx1 * (sy - v1[1]) - dy1 * (sx - v1[0])); 238f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross == 0.0F) 239f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org cross = dx1 + dy1; 240f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross < 0.0F) { 241f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* sample point is outside second edge */ 242f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org insideCount -= 1.0F; 243f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org stop = 16; 244f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 245f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else { 246f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* sample point is inside first and second edges */ 247f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org cross = (dx2 * (sy - v2[1]) - dy2 * (sx - v2[0])); 248f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross == 0.0F) 249f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org cross = dx2 + dy2; 250f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (cross < 0.0F) { 251f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org /* sample point is outside third edge */ 252f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org insideCount -= 1.0F; 253f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org stop = 16; 254f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 255f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 256f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 257f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 258f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (stop == 4) 259f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return 1.0F; 260f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else 261f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org return insideCount * (1.0F / 16.0F); 262f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 263f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 264f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 265f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 266f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic void 267f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgrgba_aa_tri(struct gl_context *ctx, 268f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v0, 269f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v1, 270f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v2) 271f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 272f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define DO_Z 273f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "s_aatritemp.h" 274f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 275f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 276f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 277f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgstatic void 278f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orggeneral_aa_tri(struct gl_context *ctx, 279f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v0, 280f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v1, 281f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org const SWvertex *v2) 282f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 283f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define DO_Z 284f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#define DO_ATTRIBS 285f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org#include "s_aatritemp.h" 286f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 287f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 288f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 289f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 290f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org/* 291f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * Examine GL state and set swrast->Triangle to an 292f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org * appropriate antialiased triangle rasterizer function. 293f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org */ 294f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.orgvoid 295f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org_swrast_set_aa_triangle_function(struct gl_context *ctx) 296f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org{ 297f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org SWcontext *swrast = SWRAST_CONTEXT(ctx); 298f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 299f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org ASSERT(ctx->Polygon.SmoothFlag); 300f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 301f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org if (ctx->Texture._EnabledCoordUnits != 0 302f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org || _swrast_use_fragment_program(ctx) 303f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org || swrast->_FogEnabled 304f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org || _mesa_need_secondary_color(ctx)) { 305f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org SWRAST_CONTEXT(ctx)->Triangle = general_aa_tri; 306f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 307f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org else { 308f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org SWRAST_CONTEXT(ctx)->Triangle = rgba_aa_tri; 309f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org } 310f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org 311f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org ASSERT(SWRAST_CONTEXT(ctx)->Triangle); 312f2ba7591b1407a7ee9209f842c50696914dc2dedkbr@chromium.org} 313