blob: ad8eab75028294ccd66631e3807fa76a975c4439 [file] [log] [blame]
/*
* 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);
}
}