Revert[2] of float color components
This reverts commit 2a2bdc698460c38ac9e24ba4abdeefec67bcba37.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1622483002
TBR=
NOTRY=True
Test-Ubuntu-GCC-ShuttleA-GPU-GTX660-x86_64-Release-Trybot seems wicked slow
Review URL: https://codereview.chromium.org/1622483002
diff --git a/tests/SkColor4fTest.cpp b/tests/SkColor4fTest.cpp
new file mode 100644
index 0000000..b09b0c4
--- /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));
+ }
+}