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 "PathOpsTestCommon.h"
9 #include "PathOpsThreadedCommon.h"
10 #include "SkIntersections.h"
11 #include "SkPathOpsLine.h"
12 #include "SkPathOpsQuad.h"
13 #include "SkReduceOrder.h"
14 #include "SkString.h"
15 
doIntersect(SkIntersections & intersections,const SkDQuad & quad,const SkDLine & line,bool & flipped)16 static int doIntersect(SkIntersections& intersections, const SkDQuad& quad, const SkDLine& line,
17                        bool& flipped) {
18     int result;
19     flipped = false;
20     if (line[0].fX == line[1].fX) {
21         double top = line[0].fY;
22         double bottom = line[1].fY;
23         flipped = top > bottom;
24         if (flipped) {
25             SkTSwap<double>(top, bottom);
26         }
27         result = intersections.vertical(quad, top, bottom, line[0].fX, flipped);
28     } else if (line[0].fY == line[1].fY) {
29         double left = line[0].fX;
30         double right = line[1].fX;
31         flipped = left > right;
32         if (flipped) {
33             SkTSwap<double>(left, right);
34         }
35         result = intersections.horizontal(quad, left, right, line[0].fY, flipped);
36     } else {
37         intersections.intersect(quad, line);
38         result = intersections.used();
39     }
40     return result;
41 }
42 
testLineIntersect(skiatest::Reporter * reporter,const SkDQuad & quad,const SkDLine & line,const double x,const double y)43 static void testLineIntersect(skiatest::Reporter* reporter, const SkDQuad& quad,
44                               const SkDLine& line, const double x, const double y) {
45     SkString pathStr;
46     pathStr.appendf("    path.moveTo(%1.9g, %1.9g);\n", quad[0].fX, quad[0].fY);
47     pathStr.appendf("    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     pathStr.appendf("    path.moveTo(%1.9g, %1.9g);\n", line[0].fX, line[0].fY);
50     pathStr.appendf("    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
testQuadLineIntersectMain(PathOpsThreadState * data)73 static 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     QuadPts q = {{{(double) ax, (double) ay}, {(double) bx, (double) by},
84             {(double) cx, (double) cy}}};
85     SkDQuad quad;
86     quad.debugSet(q.fPts);
87     SkReduceOrder reducer;
88     int order = reducer.reduce(quad);
89     if (order < 3) {
90         return;
91     }
92     for (int tIndex = 0; tIndex <= 4; ++tIndex) {
93         SkDPoint xy = quad.ptAtT(tIndex / 4.0);
94         for (int h = -2; h <= 2; ++h) {
95             for (int v = -2; v <= 2; ++v) {
96                 if (h == v && SkTAbs(h) != 1) {
97                     continue;
98                 }
99                 double x = xy.fX;
100                 double y = xy.fY;
101                 SkDLine line = {{{x - h, y - v}, {x, y}}};
102                 testLineIntersect(state.fReporter, quad, line, x, y);
103                 state.fReporter->bumpTestCount();
104                 SkDLine line2 = {{{x, y}, {x + h, y + v}}};
105                 testLineIntersect(state.fReporter, quad, line2, x, y);
106                 state.fReporter->bumpTestCount();
107                 SkDLine line3 = {{{x - h, y - v}, {x + h, y + v}}};
108                 testLineIntersect(state.fReporter, quad, line3, x, y);
109                 state.fReporter->bumpTestCount();
110             }
111         }
112     }
113 }
114 
DEF_TEST(PathOpsQuadLineIntersectionThreaded,reporter)115 DEF_TEST(PathOpsQuadLineIntersectionThreaded, reporter) {
116     initializeTests(reporter, "testQuadLineIntersect");
117     PathOpsThreadedTestRunner testRunner(reporter);
118     for (int a = 0; a < 16; ++a) {
119         for (int b = 0 ; b < 16; ++b) {
120             for (int c = 0 ; c < 16; ++c) {
121                 *testRunner.fRunnables.append() = new PathOpsThreadedRunnable(
122                         &testQuadLineIntersectMain, a, b, c, 0, &testRunner);
123             }
124             if (!reporter->allowExtendedTest()) goto finish;
125         }
126     }
127 finish:
128     testRunner.render();
129 }
130