Interpolate vertical linear gradients for improved quality.
Consolidate interpolation functions, add new faster more accurate dithering
interpolator.
git-svn-id: http://skia.googlecode.com/svn/trunk@3072 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/ColorTest.cpp b/tests/ColorTest.cpp
index 0efb892..83e2e3f 100644
--- a/tests/ColorTest.cpp
+++ b/tests/ColorTest.cpp
@@ -7,7 +7,9 @@
*/
#include "Test.h"
#include "SkColor.h"
+#include "SkColorPriv.h"
#include "SkMath.h"
+#include "SkRandom.h"
#include "SkUnPreMultiply.h"
static void test_premul(skiatest::Reporter* reporter) {
@@ -31,9 +33,49 @@
}
}
+/**
+ 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.
+*/
+/*
+static void test_interp(skiatest::Reporter* 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, SkFourByteInterp(src, dst, a0) == dst);
+ REPORTER_ASSERT(reporter, SkFourByteInterp(src, dst, a255) == src);
+ }
+}
+*/
+
+static void test_fast_interp(skiatest::Reporter* 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);
+ }
+}
static void TestColor(skiatest::Reporter* reporter) {
test_premul(reporter);
+ //test_interp(reporter);
+ test_fast_interp(reporter);
}
#include "TestClassDef.h"