1 /* 2 * Copyright 2011 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 8 #include "SkCanvas.h" 9 #include "SkEdgeClipper.h" 10 #include "SkLineClipper.h" 11 #include "SkPath.h" 12 #include "Test.h" 13 14 static void test_hairclipping(skiatest::Reporter* reporter) { 15 SkBitmap bm; 16 bm.allocN32Pixels(4, 4); 17 bm.eraseColor(SK_ColorWHITE); 18 19 SkPaint paint; 20 paint.setAntiAlias(true); 21 22 SkCanvas canvas(bm); 23 canvas.clipRect(SkRect::MakeWH(SkIntToScalar(4), SkIntToScalar(2))); 24 canvas.drawLine(1.5f, 1.5f, 25 3.5f, 3.5f, paint); 26 27 /** 28 * We had a bug where we misinterpreted the bottom of the clip, and 29 * would draw another pixel (to the right in this case) on the same 30 * last scanline. i.e. we would draw to [2,1], even though this hairline 31 * should just draw to [1,1], [2,2], [3,3] modulo the clip. 32 * 33 * The result of this entire draw should be that we only draw to [1,1] 34 * 35 * Fixed in rev. 3366 36 */ 37 for (int y = 0; y < 4; ++y) { 38 for (int x = 0; x < 4; ++x) { 39 bool nonWhite = (1 == y) && (1 == x); 40 SkPMColor c = *bm.getAddr32(x, y); 41 if (nonWhite) { 42 REPORTER_ASSERT(reporter, 0xFFFFFFFF != c); 43 } else { 44 REPORTER_ASSERT(reporter, 0xFFFFFFFF == c); 45 } 46 } 47 } 48 } 49 50 static void test_edgeclipper() { 51 SkEdgeClipper clipper(false); 52 53 const SkPoint pts[] = { 54 { 3.0995476e+010f, 42.929779f }, 55 { -3.0995163e+010f, 51.050385f }, 56 { -3.0995157e+010f, 51.050392f }, 57 { -3.0995134e+010f, 51.050400f }, 58 }; 59 60 const SkRect clip = { 0, 0, SkIntToScalar(300), SkIntToScalar(200) }; 61 62 // this should not assert, even though our choppers do a poor numerical 63 // job when computing their t values. 64 // http://code.google.com/p/skia/issues/detail?id=444 65 clipper.clipCubic(pts, clip); 66 } 67 68 static void test_intersectline(skiatest::Reporter* reporter) { 69 static const SkScalar L = 0; 70 static const SkScalar T = 0; 71 static const SkScalar R = SkIntToScalar(100); 72 static const SkScalar B = SkIntToScalar(100); 73 static const SkScalar CX = SkScalarHalf(L + R); 74 static const SkScalar CY = SkScalarHalf(T + B); 75 static const SkRect gR = { L, T, R, B }; 76 77 size_t i; 78 SkPoint dst[2]; 79 80 static const SkPoint gEmpty[] = { 81 // sides 82 { L, CY }, { L - 10, CY }, 83 { R, CY }, { R + 10, CY }, 84 { CX, T }, { CX, T - 10 }, 85 { CX, B }, { CX, B + 10 }, 86 // corners 87 { L, T }, { L - 10, T - 10 }, 88 { L, B }, { L - 10, B + 10 }, 89 { R, T }, { R + 10, T - 10 }, 90 { R, B }, { R + 10, B + 10 }, 91 }; 92 for (i = 0; i < SK_ARRAY_COUNT(gEmpty); i += 2) { 93 bool valid = SkLineClipper::IntersectLine(&gEmpty[i], gR, dst); 94 if (valid) { 95 SkDebugf("----- [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY); 96 } 97 REPORTER_ASSERT(reporter, !valid); 98 } 99 100 static const SkPoint gFull[] = { 101 // diagonals, chords 102 { L, T }, { R, B }, 103 { L, B }, { R, T }, 104 { CX, T }, { CX, B }, 105 { L, CY }, { R, CY }, 106 { CX, T }, { R, CY }, 107 { CX, T }, { L, CY }, 108 { L, CY }, { CX, B }, 109 { R, CY }, { CX, B }, 110 // edges 111 { L, T }, { L, B }, 112 { R, T }, { R, B }, 113 { L, T }, { R, T }, 114 { L, B }, { R, B }, 115 }; 116 for (i = 0; i < SK_ARRAY_COUNT(gFull); i += 2) { 117 bool valid = SkLineClipper::IntersectLine(&gFull[i], gR, dst); 118 if (!valid || memcmp(&gFull[i], dst, sizeof(dst))) { 119 SkDebugf("++++ [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY); 120 } 121 REPORTER_ASSERT(reporter, valid && !memcmp(&gFull[i], dst, sizeof(dst))); 122 } 123 124 static const SkPoint gPartial[] = { 125 { L - 10, CY }, { CX, CY }, { L, CY }, { CX, CY }, 126 { CX, T - 10 }, { CX, CY }, { CX, T }, { CX, CY }, 127 { R + 10, CY }, { CX, CY }, { R, CY }, { CX, CY }, 128 { CX, B + 10 }, { CX, CY }, { CX, B }, { CX, CY }, 129 // extended edges 130 { L, T - 10 }, { L, B + 10 }, { L, T }, { L, B }, 131 { R, T - 10 }, { R, B + 10 }, { R, T }, { R, B }, 132 { L - 10, T }, { R + 10, T }, { L, T }, { R, T }, 133 { L - 10, B }, { R + 10, B }, { L, B }, { R, B }, 134 }; 135 for (i = 0; i < SK_ARRAY_COUNT(gPartial); i += 4) { 136 bool valid = SkLineClipper::IntersectLine(&gPartial[i], gR, dst); 137 if (!valid || memcmp(&gPartial[i+2], dst, sizeof(dst))) { 138 SkDebugf("++++ [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY); 139 } 140 REPORTER_ASSERT(reporter, valid && 141 !memcmp(&gPartial[i+2], dst, sizeof(dst))); 142 } 143 144 } 145 146 DEF_TEST(Clipper, reporter) { 147 test_intersectline(reporter); 148 test_edgeclipper(); 149 test_hairclipping(reporter); 150 } 151
