/* * Copyright 2011 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "include/core/SkColor.h" #include "include/core/SkTypes.h" #include "include/core/SkUnPreMultiply.h" #include "include/private/SkColorData.h" #include "include/utils/SkRandom.h" #include "src/core/SkMathPriv.h" #include "tests/Test.h" DEF_TEST(ColorPremul, reporter) { for (int a = 0; a <= 255; a++) { for (int x = 0; x <= 255; x++) { SkColor c0 = SkColorSetARGB(a, x, x, x); SkPMColor p0 = SkPreMultiplyColor(c0); SkColor c1 = SkUnPreMultiply::PMColorToColor(p0); SkPMColor p1 = SkPreMultiplyColor(c1); // we can't promise that c0 == c1, since c0 -> p0 is a many to one // function, however, we can promise that p0 -> c1 -> p1 : p0 == p1 REPORTER_ASSERT(reporter, p0 == p1); { int ax = SkMulDiv255Ceiling(x, a); REPORTER_ASSERT(reporter, ax <= a); } } } } /** This test fails: SkFourByteInterp does *not* preserve opaque destinations. SkAlpha255To256 implemented as (alpha + 1) is faster than (alpha + (alpha >> 7)), but inaccurate, and Skia intends to phase it out. */ DEF_TEST(ColorInterp, reporter) { SkRandom r; U8CPU a0 = 0; U8CPU a255 = 255; for (int i = 0; i < 200; i++) { SkColor colorSrc = r.nextU(); SkColor colorDst = r.nextU(); SkPMColor src = SkPreMultiplyColor(colorSrc); SkPMColor dst = SkPreMultiplyColor(colorDst); if (false) { REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a0) == dst); REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a255) == src); } } } DEF_TEST(ColorFastIterp, reporter) { SkRandom r; U8CPU a0 = 0; U8CPU a255 = 255; for (int i = 0; i < 200; i++) { SkColor colorSrc = r.nextU(); SkColor colorDst = r.nextU(); SkPMColor src = SkPreMultiplyColor(colorSrc); SkPMColor dst = SkPreMultiplyColor(colorDst); REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a0) == dst); REPORTER_ASSERT(reporter, SkFastFourByteInterp(src, dst, a255) == src); } }