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 "include/core/SkString.h"
8#include "src/pathops/SkIntersections.h"
9#include "src/pathops/SkPathOpsLine.h"
10#include "src/pathops/SkPathOpsQuad.h"
11#include "src/pathops/SkReduceOrder.h"
12#include "tests/PathOpsExtendedTest.h"
13#include "tests/PathOpsTestCommon.h"
14#include "tests/PathOpsThreadedCommon.h"
15
16#include <utility>
17
18static int doIntersect(SkIntersections& intersections, const SkDQuad& quad, const SkDLine& line,
19                       bool& flipped) {
20    int result;
21    flipped = false;
22    if (line[0].fX == line[1].fX) {
23        double top = line[0].fY;
24        double bottom = line[1].fY;
25        flipped = top > bottom;
26        if (flipped) {
27            using std::swap;
28            swap(top, bottom);
29        }
30        result = intersections.vertical(quad, top, bottom, line[0].fX, flipped);
31    } else if (line[0].fY == line[1].fY) {
32        double left = line[0].fX;
33        double right = line[1].fX;
34        flipped = left > right;
35        if (flipped) {
36            using std::swap;
37            swap(left, right);
38        }
39        result = intersections.horizontal(quad, left, right, line[0].fY, flipped);
40    } else {
41        intersections.intersect(quad, line);
42        result = intersections.used();
43    }
44    return result;
45}
46
47static void testLineIntersect(skiatest::Reporter* reporter, const SkDQuad& quad,
48                              const SkDLine& line, const double x, const double y) {
49    SkString pathStr;
50    pathStr.appendf("    path.moveTo(%1.9g, %1.9g);\n", quad[0].fX, quad[0].fY);
51    pathStr.appendf("    path.quadTo(%1.9g, %1.9g, %1.9g, %1.9g);\n", quad[1].fX,
52            quad[1].fY, quad[2].fX, quad[2].fY);
53    pathStr.appendf("    path.moveTo(%1.9g, %1.9g);\n", line[0].fX, line[0].fY);
54    pathStr.appendf("    path.lineTo(%1.9g, %1.9g);\n", line[1].fX, line[1].fY);
55
56    SkIntersections intersections;
57    bool flipped = false;
58    int result = doIntersect(intersections, quad, line, flipped);
59    bool found = false;
60    for (int index = 0; index < result; ++index) {
61        double quadT = intersections[0][index];
62        SkDPoint quadXY = quad.ptAtT(quadT);
63        double lineT = intersections[1][index];
64        SkDPoint lineXY = line.ptAtT(lineT);
65        if (quadXY.approximatelyEqual(lineXY)) {
66            found = true;
67        }
68    }
69    REPORTER_ASSERT(reporter, found);
70}
71
72// find a point on a quad by choosing a t from 0 to 1
73// create a vertical span above and below the point
74// verify that intersecting the vertical span and the quad returns t
75// verify that a vertical span starting at quad[0] intersects at t=0
76// verify that a vertical span starting at quad[2] intersects at t=1
77static void testQuadLineIntersectMain(PathOpsThreadState* data)
78{
79    PathOpsThreadState& state = *data;
80    REPORTER_ASSERT(state.fReporter, data);
81    int ax = state.fA & 0x03;
82    int ay = state.fA >> 2;
83    int bx = state.fB & 0x03;
84    int by = state.fB >> 2;
85    int cx = state.fC & 0x03;
86    int cy = state.fC >> 2;
87    QuadPts q = {{{(double) ax, (double) ay}, {(double) bx, (double) by},
88            {(double) cx, (double) cy}}};
89    SkDQuad quad;
90    quad.debugSet(q.fPts);
91    SkReduceOrder reducer;
92    int order = reducer.reduce(quad);
93    if (order < 3) {
94        return;
95    }
96    for (int tIndex = 0; tIndex <= 4; ++tIndex) {
97        SkDPoint xy = quad.ptAtT(tIndex / 4.0);
98        for (int h = -2; h <= 2; ++h) {
99            for (int v = -2; v <= 2; ++v) {
100                if (h == v && SkTAbs(h) != 1) {
101                    continue;
102                }
103                double x = xy.fX;
104                double y = xy.fY;
105                SkDLine line = {{{x - h, y - v}, {x, y}}};
106                testLineIntersect(state.fReporter, quad, line, x, y);
107                state.fReporter->bumpTestCount();
108                SkDLine line2 = {{{x, y}, {x + h, y + v}}};
109                testLineIntersect(state.fReporter, quad, line2, x, y);
110                state.fReporter->bumpTestCount();
111                SkDLine line3 = {{{x - h, y - v}, {x + h, y + v}}};
112                testLineIntersect(state.fReporter, quad, line3, x, y);
113                state.fReporter->bumpTestCount();
114            }
115        }
116    }
117}
118
119DEF_TEST(PathOpsQuadLineIntersectionThreaded, reporter) {
120    initializeTests(reporter, "testQuadLineIntersect");
121    PathOpsThreadedTestRunner testRunner(reporter);
122    for (int a = 0; a < 16; ++a) {
123        for (int b = 0 ; b < 16; ++b) {
124            for (int c = 0 ; c < 16; ++c) {
125                *testRunner.fRunnables.append() = new PathOpsThreadedRunnable(
126                        &testQuadLineIntersectMain, a, b, c, 0, &testRunner);
127            }
128            if (!reporter->allowExtendedTest()) goto finish;
129        }
130    }
131finish:
132    testRunner.render();
133}
134