1/*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7#include "PathOpsExtendedTest.h"
8#include "PathOpsThreadedCommon.h"
9#include "SkIntersections.h"
10#include "SkPathOpsLine.h"
11#include "SkPathOpsQuad.h"
12#include "SkReduceOrder.h"
13
14static int doIntersect(SkIntersections& intersections, const SkDQuad& quad, const SkDLine& line,
15                       bool& flipped) {
16    int result;
17    flipped = false;
18    if (line[0].fX == line[1].fX) {
19        double top = line[0].fY;
20        double bottom = line[1].fY;
21        flipped = top > bottom;
22        if (flipped) {
23            SkTSwap<double>(top, bottom);
24        }
25        result = intersections.vertical(quad, top, bottom, line[0].fX, flipped);
26    } else if (line[0].fY == line[1].fY) {
27        double left = line[0].fX;
28        double right = line[1].fX;
29        flipped = left > right;
30        if (flipped) {
31            SkTSwap<double>(left, right);
32        }
33        result = intersections.horizontal(quad, left, right, line[0].fY, flipped);
34    } else {
35        intersections.intersect(quad, line);
36        result = intersections.used();
37    }
38    return result;
39}
40
41static void testLineIntersect(skiatest::Reporter* reporter, const SkDQuad& quad,
42                              const SkDLine& line, const double x, const double y) {
43    char pathStr[1024];
44    sk_bzero(pathStr, sizeof(pathStr));
45    char* str = pathStr;
46    str += sprintf(str, "    path.moveTo(%1.9g, %1.9g);\n", quad[0].fX, quad[0].fY);
47    str += sprintf(str, "    path.quadTo(%1.9g, %1.9g, %1.9g, %1.9g);\n", quad[1].fX,
48            quad[1].fY, quad[2].fX, quad[2].fY);
49    str += sprintf(str, "    path.moveTo(%1.9g, %1.9g);\n", line[0].fX, line[0].fY);
50    str += sprintf(str, "    path.lineTo(%1.9g, %1.9g);\n", line[1].fX, line[1].fY);
51
52    SkIntersections intersections;
53    bool flipped = false;
54    int result = doIntersect(intersections, quad, line, flipped);
55    bool found = false;
56    for (int index = 0; index < result; ++index) {
57        double quadT = intersections[0][index];
58        SkDPoint quadXY = quad.ptAtT(quadT);
59        double lineT = intersections[1][index];
60        SkDPoint lineXY = line.ptAtT(lineT);
61        if (quadXY.approximatelyEqual(lineXY)) {
62            found = true;
63        }
64    }
65    REPORTER_ASSERT(reporter, found);
66}
67
68// find a point on a quad by choosing a t from 0 to 1
69// create a vertical span above and below the point
70// verify that intersecting the vertical span and the quad returns t
71// verify that a vertical span starting at quad[0] intersects at t=0
72// verify that a vertical span starting at quad[2] intersects at t=1
73static void testQuadLineIntersectMain(PathOpsThreadState* data)
74{
75    PathOpsThreadState& state = *data;
76    REPORTER_ASSERT(state.fReporter, data);
77    int ax = state.fA & 0x03;
78    int ay = state.fA >> 2;
79    int bx = state.fB & 0x03;
80    int by = state.fB >> 2;
81    int cx = state.fC & 0x03;
82    int cy = state.fC >> 2;
83    SkDQuad quad = {{{(double) ax, (double) ay}, {(double) bx, (double) by},
84            {(double) cx, (double) cy}}};
85    SkReduceOrder reducer;
86    int order = reducer.reduce(quad);
87    if (order < 3) {
88        return;
89    }
90    for (int tIndex = 0; tIndex <= 4; ++tIndex) {
91        SkDPoint xy = quad.ptAtT(tIndex / 4.0);
92        for (int h = -2; h <= 2; ++h) {
93            for (int v = -2; v <= 2; ++v) {
94                if (h == v && abs(h) != 1) {
95                    continue;
96                }
97                double x = xy.fX;
98                double y = xy.fY;
99                SkDLine line = {{{x - h, y - v}, {x, y}}};
100                testLineIntersect(state.fReporter, quad, line, x, y);
101                state.fReporter->bumpTestCount();
102                SkDLine line2 = {{{x, y}, {x + h, y + v}}};
103                testLineIntersect(state.fReporter, quad, line2, x, y);
104                state.fReporter->bumpTestCount();
105                SkDLine line3 = {{{x - h, y - v}, {x + h, y + v}}};
106                testLineIntersect(state.fReporter, quad, line3, x, y);
107                state.fReporter->bumpTestCount();
108            }
109        }
110    }
111}
112
113DEF_TEST(PathOpsQuadLineIntersectionThreaded, reporter) {
114    initializeTests(reporter, "testQuadLineIntersect");
115    PathOpsThreadedTestRunner testRunner(reporter);
116    for (int a = 0; a < 16; ++a) {
117        for (int b = 0 ; b < 16; ++b) {
118            for (int c = 0 ; c < 16; ++c) {
119                    *testRunner.fRunnables.append() = SkNEW_ARGS(PathOpsThreadedRunnable,
120                            (&testQuadLineIntersectMain, a, b, c, 0, &testRunner));
121            }
122            if (!reporter->allowExtendedTest()) goto finish;
123        }
124    }
125finish:
126    testRunner.render();
127}
128