1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 #include "Test.h" 9 #include "SkColor.h" 10 #include "SkColorPriv.h" 11 #include "SkMathPriv.h" 12 #include "SkRandom.h" 13 #include "SkUnPreMultiply.h" 14 15 #define GetPackedR16As32(packed) (SkGetPackedR16(dc) << (8 - SK_R16_BITS)) 16 #define GetPackedG16As32(packed) (SkGetPackedG16(dc) << (8 - SK_G16_BITS)) 17 #define GetPackedB16As32(packed) (SkGetPackedB16(dc) << (8 - SK_B16_BITS)) 18 19 static inline bool S32A_D565_Blend_0(SkPMColor sc, uint16_t dc, U8CPU alpha) { 20 unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha); 21 unsigned dr = SkMulS16(SkPacked32ToR16(sc), alpha) + SkMulS16(SkGetPackedR16(dc), dst_scale); 22 unsigned dg = SkMulS16(SkPacked32ToG16(sc), alpha) + SkMulS16(SkGetPackedG16(dc), dst_scale); 23 24 unsigned rr = SkDiv255Round(dr); 25 unsigned rg = SkDiv255Round(dg); 26 27 if (rr <= 31 && rg <= 63) { 28 return true; 29 } 30 return false; 31 } 32 33 static inline bool S32A_D565_Blend_01(SkPMColor sc, uint16_t dc, U8CPU alpha) { 34 unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha); 35 unsigned dr = SkMulS16(SkGetPackedR32(sc), alpha) + SkMulS16(SkGetPackedR16(dc) << 3, dst_scale); 36 unsigned dg = SkMulS16(SkGetPackedG32(sc), alpha) + SkMulS16(SkGetPackedG16(dc) << 2, dst_scale); 37 38 unsigned rr = SkDiv255Round(dr) >> 3; 39 unsigned rg = SkDiv255Round(dg) >> 2; 40 41 if (rr <= 31 && rg <= 63) { 42 return true; 43 } 44 return false; 45 } 46 47 static inline bool S32A_D565_Blend_02(SkPMColor sc, uint16_t dc, U8CPU alpha) { 48 unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha); 49 unsigned dr = SkMulS16(SkGetPackedR32(sc), alpha) + SkMulS16(GetPackedR16As32(dc), dst_scale); 50 unsigned dg = SkMulS16(SkGetPackedG32(sc), alpha) + SkMulS16(GetPackedG16As32(dc), dst_scale); 51 unsigned db = SkMulS16(SkGetPackedB32(sc), alpha) + SkMulS16(GetPackedB16As32(dc), dst_scale); 52 int rc = SkPack888ToRGB16(SkDiv255Round(dr), 53 SkDiv255Round(dg), 54 SkDiv255Round(db)); 55 56 unsigned rr = SkGetPackedR16(rc); 57 unsigned rg = SkGetPackedG16(rc); 58 59 if (rr <= 31 && rg <= 63) { 60 return true; 61 } 62 return false; 63 } 64 65 static inline bool S32A_D565_Blend_1(SkPMColor sc, uint16_t dc, U8CPU alpha) { 66 unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha); 67 unsigned dr = (SkMulS16(SkGetPackedR32(sc), alpha) >> 3) + SkMulS16(SkGetPackedR16(dc), dst_scale); 68 unsigned dg = (SkMulS16(SkGetPackedG32(sc), alpha) >> 2) + SkMulS16(SkGetPackedG16(dc), dst_scale); 69 70 unsigned rr = SkDiv255Round(dr); 71 unsigned rg = SkDiv255Round(dg); 72 73 if (rr <= 31 && rg <= 63) { 74 return true; 75 } 76 return false; 77 } 78 79 static inline int SkDiv65025Round(int x) { 80 return (x + 65025/2) / 65025; 81 // return x / 65025; 82 } 83 static inline bool S32A_D565_Blend_2(SkPMColor sc, uint16_t dc, U8CPU alpha) { 84 unsigned dst_scale = 255*255 - SkGetPackedA32(sc) * alpha; 85 alpha *= 255; 86 unsigned dr = (SkGetPackedR32(sc) >> 3) * alpha + SkGetPackedR16(dc) * dst_scale; 87 unsigned dg = (SkGetPackedG32(sc) >> 2) * alpha + SkGetPackedG16(dc) * dst_scale; 88 89 unsigned rr = SkDiv65025Round(dr); 90 unsigned rg = SkDiv65025Round(dg); 91 92 if (rr <= 31 && rg <= 63) { 93 return true; 94 } 95 return false; 96 } 97 98 static inline void test_565blend() { 99 int total_failures = 0; 100 for (int global_alpha = 0; global_alpha <= 255; ++global_alpha) { 101 int failures = 0; 102 int total = 0; 103 for (int src_a = 0; src_a <= 255; ++src_a) { 104 for (int src_c = 0; src_c <= src_a; ++src_c) { 105 SkPMColor sc = SkPackARGB32(src_a, src_c, src_c, src_c); 106 for (int dst_r = 0; dst_r <= 31; ++dst_r) { 107 for (int dst_g = 0; dst_g <= 63; ++dst_g) { 108 uint16_t dc = SkPackRGB16(dst_r, dst_g, dst_r); 109 failures += !S32A_D565_Blend_0(sc, dc, global_alpha); 110 total += 1; 111 } 112 } 113 } 114 } 115 SkDebugf("global_alpha=%d failures=%d total=%d %g\n", global_alpha, failures, total, failures * 100.0 / total); 116 total_failures += failures; 117 } 118 SkDebugf("total failures %d\n", total_failures); 119 } 120 121 static inline void test_premul(skiatest::Reporter* reporter) { 122 for (int a = 0; a <= 255; a++) { 123 for (int x = 0; x <= 255; x++) { 124 SkColor c0 = SkColorSetARGB(a, x, x, x); 125 SkPMColor p0 = SkPreMultiplyColor(c0); 126 127 SkColor c1 = SkUnPreMultiply::PMColorToColor(p0); 128 SkPMColor p1 = SkPreMultiplyColor(c1); 129 130 // we can't promise that c0 == c1, since c0 -> p0 is a many to one 131 // function, however, we can promise that p0 -> c1 -> p1 : p0 == p1 132 REPORTER_ASSERT(reporter, p0 == p1); 133 134 { 135 int ax = SkMulDiv255Ceiling(x, a); 136 REPORTER_ASSERT(reporter, ax <= a); 137 } 138 } 139 } 140 } 141 142 /** 143 This test fails: SkFourByteInterp does *not* preserve opaque destinations. 144 SkAlpha255To256 implemented as (alpha + 1) is faster than 145 (alpha + (alpha >> 7)), but inaccurate, and Skia intends to phase it out. 146 */ 147 /* 148 static void test_interp(skiatest::Reporter* reporter) { 149 SkMWCRandom r; 150 151 U8CPU a0 = 0; 152 U8CPU a255 = 255; 153 for (int i = 0; i < 200; i++) { 154 SkColor colorSrc = r.nextU(); 155 SkColor colorDst = r.nextU(); 156 SkPMColor src = SkPreMultiplyColor(colorSrc); 157 SkPMColor dst = SkPreMultiplyColor(colorDst); 158 159 REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a0) == dst); 160 REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a255) == src); 161 } 162 } 163 */ 164 165 static inline void test_fast_interp(skiatest::Reporter* reporter) { 166 SkMWCRandom r; 167 168 U8CPU a0 = 0; 169 U8CPU a255 = 255; 170 for (int i = 0; i < 200; i++) { 171 SkColor colorSrc = r.nextU(); 172 SkColor colorDst = r.nextU(); 173 SkPMColor src = SkPreMultiplyColor(colorSrc); 174 SkPMColor dst = SkPreMultiplyColor(colorDst); 175 176 REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a0) == dst); 177 REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a255) == src); 178 } 179 } 180 181 static void TestColor(skiatest::Reporter* reporter) { 182 test_premul(reporter); 183 //test_interp(reporter); 184 test_fast_interp(reporter); 185 // test_565blend(); 186 } 187 188 #include "TestClassDef.h" 189 DEFINE_TESTCLASS("Color", ColorTestClass, TestColor) 190
