From 353c148d8e8c9031daca34c6f9d6bcc6f08706c7 Mon Sep 17 00:00:00 2001 From: reed Date: Thu, 21 Jan 2016 15:29:10 -0800 Subject: experiment: float color components BUG=skia: GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1617813002 Review URL: https://codereview.chromium.org/1617813002 --- tests/SkColor4fTest.cpp | 62 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 tests/SkColor4fTest.cpp (limited to 'tests/SkColor4fTest.cpp') diff --git a/tests/SkColor4fTest.cpp b/tests/SkColor4fTest.cpp new file mode 100644 index 0000000000..b09b0c479a --- /dev/null +++ b/tests/SkColor4fTest.cpp @@ -0,0 +1,62 @@ +/* + * Copyright 2016 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#include "SkColor.h" +#include "SkShader.h" +#include "SkColorMatrixFilter.h" +#include "Test.h" +#include "SkRandom.h" + +DEF_TEST(SkColor4f_FromColor, reporter) { + const struct { + SkColor fC; + SkColor4f fC4; + } recs[] = { + { SK_ColorBLACK, { 1, 0, 0, 0 } }, + { SK_ColorWHITE, { 1, 1, 1, 1 } }, + { SK_ColorRED, { 1, 1, 0, 0 } }, + { SK_ColorGREEN, { 1, 0, 1, 0 } }, + { SK_ColorBLUE, { 1, 0, 0, 1 } }, + { 0, { 0, 0, 0, 0 } }, + { 0x55AAFF00, { 1/3.0f, 2/3.0f, 1, 0 } }, + }; + + for (const auto& r : recs) { + SkColor4f c4 = SkColor4f::FromColor(r.fC); + REPORTER_ASSERT(reporter, c4 == r.fC4); + } +} + +static bool nearly_equal(float a, float b) { + const float kTolerance = 1.0f / (1 << 20); + return fabsf(a - b) < kTolerance; +} + +DEF_TEST(SkColor4f_premul, reporter) { + SkRandom rand; + + for (int i = 0; i < 1000000; ++i) { + // First just test opaque colors, so that the premul should be exact + SkColor4f c4 { + 1, rand.nextUScalar1(), rand.nextUScalar1(), rand.nextUScalar1() + }; + SkPM4f pm4 = c4.premul(); + REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA); + REPORTER_ASSERT(reporter, pm4.fVec[SK_R_INDEX] == c4.fA * c4.fR); + REPORTER_ASSERT(reporter, pm4.fVec[SK_G_INDEX] == c4.fA * c4.fG); + REPORTER_ASSERT(reporter, pm4.fVec[SK_B_INDEX] == c4.fA * c4.fB); + + // We compare with a tolerance, in case our premul multiply is implemented at slightly + // different precision than the test code. + c4.fA = rand.nextUScalar1(); + pm4 = c4.premul(); + REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA); + REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_R_INDEX], c4.fA * c4.fR)); + REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_G_INDEX], c4.fA * c4.fG)); + REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_B_INDEX], c4.fA * c4.fB)); + } +} -- cgit v1.2.3