1 /* 2 * Copyright 2017 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 "Test.h" 8 #include "SkInsetConvexPolygon.h" 9 10 static bool is_convex(const SkTDArray<SkPoint>& poly) { 11 if (poly.count() < 3) { 12 return false; 13 } 14 15 SkVector v0 = poly[0] - poly[poly.count() - 1]; 16 SkVector v1 = poly[1] - poly[poly.count() - 1]; 17 SkScalar winding = v0.cross(v1); 18 19 for (int i = 0; i < poly.count()-1; ++i) { 20 int j = i + 1; 21 int k = (i + 2) % poly.count(); 22 23 SkVector v0 = poly[j] - poly[i]; 24 SkVector v1 = poly[k] - poly[i]; 25 SkScalar perpDot = v0.cross(v1); 26 if (winding*perpDot < 0) { 27 return false; 28 } 29 } 30 31 return true; 32 } 33 34 DEF_TEST(InsetConvexPoly, reporter) { 35 SkTDArray<SkPoint> rrectPoly; 36 37 // round rect 38 *rrectPoly.push() = SkPoint::Make(-100, 55); 39 *rrectPoly.push() = SkPoint::Make(100, 55); 40 *rrectPoly.push() = SkPoint::Make(100 + 2.5f, 50 + 4.330127f); 41 *rrectPoly.push() = SkPoint::Make(100 + 3.535534f, 50 + 3.535534f); 42 *rrectPoly.push() = SkPoint::Make(100 + 4.330127f, 50 + 2.5f); 43 *rrectPoly.push() = SkPoint::Make(105, 50); 44 *rrectPoly.push() = SkPoint::Make(105, -50); 45 *rrectPoly.push() = SkPoint::Make(100 + 4.330127f, -50 - 2.5f); 46 *rrectPoly.push() = SkPoint::Make(100 + 3.535534f, -50 - 3.535534f); 47 *rrectPoly.push() = SkPoint::Make(100 + 2.5f, -50 - 4.330127f); 48 *rrectPoly.push() = SkPoint::Make(100, -55); 49 *rrectPoly.push() = SkPoint::Make(-100, -55); 50 *rrectPoly.push() = SkPoint::Make(-100 - 2.5f, -50 - 4.330127f); 51 *rrectPoly.push() = SkPoint::Make(-100 - 3.535534f, -50 - 3.535534f); 52 *rrectPoly.push() = SkPoint::Make(-100 - 4.330127f, -50 - 2.5f); 53 *rrectPoly.push() = SkPoint::Make(-105, -50); 54 *rrectPoly.push() = SkPoint::Make(-105, 50); 55 *rrectPoly.push() = SkPoint::Make(-100 - 4.330127f, 50 + 2.5f); 56 *rrectPoly.push() = SkPoint::Make(-100 - 3.535534f, 50 + 3.535534f); 57 *rrectPoly.push() = SkPoint::Make(-100 - 2.5f, 50 + 4.330127f); 58 REPORTER_ASSERT(reporter, is_convex(rrectPoly)); 59 60 // inset a little 61 SkTDArray<SkPoint> insetPoly; 62 bool result = SkInsetConvexPolygon(&rrectPoly[0], rrectPoly.count(), 3, &insetPoly); 63 REPORTER_ASSERT(reporter, result); 64 REPORTER_ASSERT(reporter, is_convex(insetPoly)); 65 66 // inset to rect 67 result = SkInsetConvexPolygon(&rrectPoly[0], rrectPoly.count(), 10, &insetPoly); 68 REPORTER_ASSERT(reporter, result); 69 REPORTER_ASSERT(reporter, is_convex(insetPoly)); 70 REPORTER_ASSERT(reporter, insetPoly.count() == 4); 71 if (insetPoly.count() == 4) { 72 REPORTER_ASSERT(reporter, insetPoly[0].equals(-95, 45)); 73 REPORTER_ASSERT(reporter, insetPoly[1].equals(95, 45)); 74 REPORTER_ASSERT(reporter, insetPoly[2].equals(95, -45)); 75 REPORTER_ASSERT(reporter, insetPoly[3].equals(-95, -45)); 76 } 77 78 // just to full inset 79 // fails, but outputs a line segment 80 result = SkInsetConvexPolygon(&rrectPoly[0], rrectPoly.count(), 55, &insetPoly); 81 REPORTER_ASSERT(reporter, !result); 82 REPORTER_ASSERT(reporter, !is_convex(insetPoly)); 83 REPORTER_ASSERT(reporter, insetPoly.count() == 2); 84 if (insetPoly.count() == 2) { 85 REPORTER_ASSERT(reporter, insetPoly[0].equals(-50, 0)); 86 REPORTER_ASSERT(reporter, insetPoly[1].equals(50, 0)); 87 } 88 89 // past full inset 90 result = SkInsetConvexPolygon(&rrectPoly[0], rrectPoly.count(), 75, &insetPoly); 91 REPORTER_ASSERT(reporter, !result); 92 REPORTER_ASSERT(reporter, insetPoly.count() == 0); 93 94 // troublesome case 95 SkTDArray<SkPoint> clippedRRectPoly; 96 *clippedRRectPoly.push() = SkPoint::Make(335.928101f, 428.219055f); 97 *clippedRRectPoly.push() = SkPoint::Make(330.414459f, 423.034912f); 98 *clippedRRectPoly.push() = SkPoint::Make(325.749084f, 417.395508f); 99 *clippedRRectPoly.push() = SkPoint::Make(321.931946f, 411.300842f); 100 *clippedRRectPoly.push() = SkPoint::Make(318.963074f, 404.750977f); 101 *clippedRRectPoly.push() = SkPoint::Make(316.842468f, 397.745850f); 102 *clippedRRectPoly.push() = SkPoint::Make(315.570068f, 390.285522f); 103 *clippedRRectPoly.push() = SkPoint::Make(315.145966f, 382.369965f); 104 *clippedRRectPoly.push() = SkPoint::Make(315.570068f, 374.454346f); 105 *clippedRRectPoly.push() = SkPoint::Make(316.842468f, 366.994019f); 106 *clippedRRectPoly.push() = SkPoint::Make(318.963074f, 359.988892f); 107 *clippedRRectPoly.push() = SkPoint::Make(321.931946f, 353.439056f); 108 *clippedRRectPoly.push() = SkPoint::Make(325.749084f, 347.344421f); 109 *clippedRRectPoly.push() = SkPoint::Make(330.414459f, 341.705017f); 110 *clippedRRectPoly.push() = SkPoint::Make(335.928101f, 336.520813f); 111 *clippedRRectPoly.push() = SkPoint::Make(342.289948f, 331.791901f); 112 *clippedRRectPoly.push() = SkPoint::Make(377.312134f, 331.791901f); 113 *clippedRRectPoly.push() = SkPoint::Make(381.195313f, 332.532593f); 114 *clippedRRectPoly.push() = SkPoint::Make(384.464935f, 334.754700f); 115 *clippedRRectPoly.push() = SkPoint::Make(386.687042f, 338.024292f); 116 *clippedRRectPoly.push() = SkPoint::Make(387.427765f, 341.907532f); 117 *clippedRRectPoly.push() = SkPoint::Make(387.427765f, 422.832367f); 118 *clippedRRectPoly.push() = SkPoint::Make(386.687042f, 426.715576f); 119 *clippedRRectPoly.push() = SkPoint::Make(384.464935f, 429.985168f); 120 *clippedRRectPoly.push() = SkPoint::Make(381.195313f, 432.207275f); 121 *clippedRRectPoly.push() = SkPoint::Make(377.312134f, 432.947998f); 122 *clippedRRectPoly.push() = SkPoint::Make(342.289948f, 432.947998f); 123 REPORTER_ASSERT(reporter, is_convex(clippedRRectPoly)); 124 125 result = SkInsetConvexPolygon(&clippedRRectPoly[0], clippedRRectPoly.count(), 32.3699417f, 126 &insetPoly); 127 REPORTER_ASSERT(reporter, result); 128 REPORTER_ASSERT(reporter, is_convex(insetPoly)); 129 } 130