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 "SkColor.h" 9 #include "SkColorPriv.h" 10 #include "SkMathPriv.h" 11 #include "SkRandom.h" 12 #include "SkUnPreMultiply.h" 13 #include "Test.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 void test_premul(skiatest::Reporter* reporter) { 20 for (int a = 0; a <= 255; a++) { 21 for (int x = 0; x <= 255; x++) { 22 SkColor c0 = SkColorSetARGB(a, x, x, x); 23 SkPMColor p0 = SkPreMultiplyColor(c0); 24 25 SkColor c1 = SkUnPreMultiply::PMColorToColor(p0); 26 SkPMColor p1 = SkPreMultiplyColor(c1); 27 28 // we can't promise that c0 == c1, since c0 -> p0 is a many to one 29 // function, however, we can promise that p0 -> c1 -> p1 : p0 == p1 30 REPORTER_ASSERT(reporter, p0 == p1); 31 32 { 33 int ax = SkMulDiv255Ceiling(x, a); 34 REPORTER_ASSERT(reporter, ax <= a); 35 } 36 } 37 } 38 } 39 40 /** 41 This test fails: SkFourByteInterp does *not* preserve opaque destinations. 42 SkAlpha255To256 implemented as (alpha + 1) is faster than 43 (alpha + (alpha >> 7)), but inaccurate, and Skia intends to phase it out. 44 */ 45 /* 46 static void test_interp(skiatest::Reporter* reporter) { 47 SkRandom r; 48 49 U8CPU a0 = 0; 50 U8CPU a255 = 255; 51 for (int i = 0; i < 200; i++) { 52 SkColor colorSrc = r.nextU(); 53 SkColor colorDst = r.nextU(); 54 SkPMColor src = SkPreMultiplyColor(colorSrc); 55 SkPMColor dst = SkPreMultiplyColor(colorDst); 56 57 REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a0) == dst); 58 REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a255) == src); 59 } 60 } 61 */ 62 63 static inline void test_fast_interp(skiatest::Reporter* reporter) { 64 SkRandom r; 65 66 U8CPU a0 = 0; 67 U8CPU a255 = 255; 68 for (int i = 0; i < 200; i++) { 69 SkColor colorSrc = r.nextU(); 70 SkColor colorDst = r.nextU(); 71 SkPMColor src = SkPreMultiplyColor(colorSrc); 72 SkPMColor dst = SkPreMultiplyColor(colorDst); 73 74 REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a0) == dst); 75 REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a255) == src); 76 } 77 } 78 79 DEF_TEST(Color, reporter) { 80 test_premul(reporter); 81 //test_interp(reporter); 82 test_fast_interp(reporter); 83 //test_565blend(); 84 } 85
