blob: cd0fa5935a3d57b921c6c90b5ba7c06f545e346e [file] [log] [blame]
/*
* 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 "SkColorSpaceXformSteps.h"
#include "SkRasterPipeline.h"
#include "SkTypes.h"
#include "Test.h"
#include <math.h>
DEF_TEST(srgb_roundtrip, r) {
for (int normalized = 0; normalized < 2; normalized++) {
uint32_t reds[256];
for (int i = 0; i < 256; i++) {
reds[i] = i;
}
SkRasterPipeline_MemoryCtx ptr = { reds, 0 };
sk_sp<SkColorSpace> sRGB = SkColorSpace::MakeSRGB(),
linear = sRGB->makeLinearGamma();
const SkAlphaType upm = kUnpremul_SkAlphaType;
SkColorSpaceXformSteps linearize{ sRGB.get(),upm, linear.get(),upm},
reencode {linear.get(),upm, sRGB.get(),upm};
SkRasterPipeline_<256> p;
p.append(SkRasterPipeline::load_8888, &ptr);
linearize.apply(&p, !!normalized);
reencode .apply(&p, !!normalized);
p.append(SkRasterPipeline::store_8888, &ptr);
p.run(0,0,256,1);
for (int i = 0; i < 256; i++) {
if (reds[i] != (uint32_t)i) {
ERRORF(r, "%d doesn't round trip, %d", i, reds[i]);
}
}
}
}
DEF_TEST(srgb_edge_cases, r) {
// We need to run at least 4 pixels to make sure we hit all specializations.
float colors[4][4] = { {0,1,1,1}, {0,0,0,0}, {0,0,0,0}, {0,0,0,0} };
auto& color = colors[0];
SkRasterPipeline_MemoryCtx dst = { &color, 0 };
sk_sp<SkColorSpace> sRGB = SkColorSpace::MakeSRGB(),
linear = sRGB->makeLinearGamma();
const SkAlphaType upm = kUnpremul_SkAlphaType;
SkColorSpaceXformSteps steps {linear.get(),upm, sRGB.get(),upm};
SkSTArenaAlloc<256> alloc;
SkRasterPipeline p(&alloc);
p.append_constant_color(&alloc, color);
steps.apply(&p, true/*inputs are normalized*/);
p.append(SkRasterPipeline::store_f32, &dst);
p.run(0,0,4,1);
if (color[0] != 0.0f) {
ERRORF(r, "expected to_srgb() to map 0.0f to 0.0f, got %f", color[0]);
}
if (color[1] != 1.0f) {
float f = color[1];
uint32_t x;
memcpy(&x, &f, 4);
ERRORF(r, "expected to_srgb() to map 1.0f to 1.0f, got %f (%08x)", color[1], x);
}
}
// Linearize and then re-encode pixel values, testing that the output is close to the input.
static void test_roundtripping(skiatest::Reporter* r,
sk_sp<SkColorSpace> cs,
float range,
float tolerance,
bool normalized) {
static const int kSteps = 128;
SkColor4f rgba[kSteps];
auto expected = [=](int i) {
float scale = range / (3*kSteps);
return SkColor4f{
(3*i+0) * scale,
(3*i+1) * scale,
(3*i+2) * scale,
1.0f,
};
};
for (int i = 0; i < kSteps; i++) {
rgba[i] = expected(i);
}
SkRasterPipeline_MemoryCtx ptr = { rgba, 0 };
sk_sp<SkColorSpace> linear = cs->makeLinearGamma();
const SkAlphaType upm = kUnpremul_SkAlphaType;
SkColorSpaceXformSteps linearize{ cs.get(),upm, linear.get(),upm},
reencode {linear.get(),upm, cs.get(),upm};
SkRasterPipeline_<256> p;
p.append(SkRasterPipeline::load_f32, &ptr);
linearize.apply(&p, normalized);
reencode .apply(&p, normalized);
p.append(SkRasterPipeline::store_f32, &ptr);
p.run(0,0,kSteps,1);
auto close = [=](float x, float y) {
return x == y
|| (x/y < tolerance && y/x < tolerance);
};
for (int i = 0; i < kSteps; i++) {
SkColor4f want = expected(i);
#if 0
SkDebugf("got %g %g %g, want %g %g %g\n",
rgba[i].fR, rgba[i].fG, rgba[i].fB,
want.fR, want.fG, want.fB);
#endif
REPORTER_ASSERT(r, close(rgba[i].fR, want.fR));
REPORTER_ASSERT(r, close(rgba[i].fG, want.fG));
REPORTER_ASSERT(r, close(rgba[i].fB, want.fB));
}
}
DEF_TEST(srgb_roundtrip_extended, r) {
// We're lying when we set normalized=true, but it allows us to test the to_srgb/from_srgb path.
test_roundtripping(r, SkColorSpace::MakeSRGB(), 2.0f, 1.025f, true);
// This normalized=false path should have much better round-tripping properties.
test_roundtripping(r, SkColorSpace::MakeSRGB(), 10000.0f, 1.001f, false);
}