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 
16 #include <utility>
17 
doIntersect(SkIntersections & intersections,const SkDQuad & quad,const SkDLine & line,bool & flipped)18 static 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 
testLineIntersect(skiatest::Reporter * reporter,const SkDQuad & quad,const SkDLine & line,const double x,const double y)47 static 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
testQuadLineIntersectMain(PathOpsThreadState * data)77 static 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 
DEF_TEST(PathOpsQuadLineIntersectionThreaded,reporter)119 DEF_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     }
131 finish:
132     testRunner.render();
133 }
134