skia2/gm/gammaencodedpremul.cpp
Matt Sarett 35b8b26eee Add gm to compare premuls in dst vs. src color space
BUG=skia:

Change-Id: I36755f4bbc405a8af12990573e1f554df012b30a
Reviewed-on: https://skia-review.googlesource.com/9402
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2017-03-08 17:07:59 +00:00

132 lines
5.0 KiB
C++

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm.h"
#include "SkColorSpaceXform.h"
#include "SkColorSpaceXformPriv.h"
#include "SkOpts.h"
#include "SkUtils.h"
static void clamp_to_alpha(uint32_t* pixels, int count) {
for (int i = 0; i < count; i++) {
uint8_t a = SkGetPackedA32(pixels[i]);
uint8_t r = SkGetPackedR32(pixels[i]);
uint8_t g = SkGetPackedG32(pixels[i]);
uint8_t b = SkGetPackedB32(pixels[i]);
pixels[i] = SkPackARGB32(a,
SkTMin(a, r),
SkTMin(a, g),
SkTMin(a, b));
}
}
class GammaEncodedPremulGM : public skiagm::GM {
public:
GammaEncodedPremulGM(sk_sp<SkColorSpace> dst, sk_sp<SkColorSpace> src, const char* desc)
: fDstSpace(dst)
, fSrcSpace(src)
, fXform(SkColorSpaceXform::New(src.get(), dst.get()))
, fName(SkStringPrintf("gamma_encoded_premul_dst-v-src_%s", desc))
{
int i = 0;
for (int r = 0; r < kColorSteps; r++) {
for (int g = 0; g < kColorSteps; g++) {
for (int b = 0; b < kColorSteps; b++) {
fColors[i++] = SkColorSetARGBInline(0xFF,
r * kColorScale,
g * kColorScale,
b * kColorScale);
}
}
}
}
protected:
virtual SkISize onISize() override {
return SkISize::Make(kAlphaMax, kNumColors * 2 * kStripeHeight);
}
SkString onShortName() override {
return fName;
}
void onDraw(SkCanvas* canvas) override {
if (canvas->imageInfo().isOpaque()) {
return;
}
SkBitmap bitmap;
SkImageInfo bitmapInfo = SkImageInfo::MakeN32Premul(kAlphaMax, 1,
canvas->imageInfo().refColorSpace());
bitmap.allocPixels(bitmapInfo);
uint32_t* pixels = bitmap.getAddr32(0, 0);
for (int i = 0; i < kNumColors; i++) {
// Create an entire row of the same color, with the alpha from 0 to kAlphaMax.
uint32_t row[kAlphaMax];
sk_memset32(row, fColors[i], kAlphaMax);
for (int a = 0; a < kAlphaMax; a++) {
row[a] = (row[a] & 0x00FFFFFF) | (a << 24);
}
// Tranform row to dst, then premultiply.
fXform->apply(select_xform_format(kN32_SkColorType), pixels,
SkColorSpaceXform::kBGRA_8888_ColorFormat, row, kAlphaMax,
kUnpremul_SkAlphaType);
SkOpts::RGBA_to_rgbA(pixels, pixels, kAlphaMax);
// Write the dst space premultiplied row to the canvas.
for (int j = 0; j < kStripeHeight; j++) {
canvas->drawBitmap(bitmap, 0, 2 * i * kStripeHeight + j);
}
// Premultiply, then transform the row to dst.
SkOpts::RGBA_to_rgbA(pixels, row, kAlphaMax);
fXform->apply(select_xform_format(kN32_SkColorType), pixels,
SkColorSpaceXform::kBGRA_8888_ColorFormat, pixels, kAlphaMax,
kUnpremul_SkAlphaType);
clamp_to_alpha(pixels, kAlphaMax);
// Write the src space premultiplied row to the canvas.
for (int j = 0; j < kStripeHeight; j++) {
canvas->drawBitmap(bitmap, 0, (2 * i + 1) * kStripeHeight + j);
}
}
}
private:
static constexpr int kColorSteps = 4;
static constexpr int kNumColors = kColorSteps * kColorSteps * kColorSteps;
static constexpr int kColorScale = 255 / (kColorSteps - 1);
static constexpr int kStripeHeight = 10;
static constexpr int kAlphaMax = 255;
sk_sp<SkColorSpace> fDstSpace;
sk_sp<SkColorSpace> fSrcSpace;
std::unique_ptr<SkColorSpaceXform> fXform;
SkString fName;
SkColor fColors[kNumColors];
typedef GM INHERITED;
};
DEF_GM(return new GammaEncodedPremulGM(SkColorSpace::MakeSRGB(),
SkColorSpace::MakeRGB(SkColorSpace::kSRGB_RenderTargetGamma, SkColorSpace::kRec2020_Gamut),
"toWideGamut");)
DEF_GM(return new GammaEncodedPremulGM(SkColorSpace::MakeRGB(SkColorSpace::kSRGB_RenderTargetGamma,
SkColorSpace::kRec2020_Gamut), SkColorSpace::MakeSRGB(), "fromWideGamut");)
DEF_GM(return new GammaEncodedPremulGM(SkColorSpace::MakeSRGB(),
SkColorSpace::MakeRGB(SkColorSpace::kLinear_RenderTargetGamma, SkColorSpace::kSRGB_Gamut),
"toLinear");)
DEF_GM(return new GammaEncodedPremulGM(
SkColorSpace::MakeRGB(SkColorSpace::kLinear_RenderTargetGamma, SkColorSpace::kSRGB_Gamut),
SkColorSpace::MakeSRGB(), "fromLinear");)
DEF_GM(return new GammaEncodedPremulGM(
SkColorSpace::MakeRGB({ 1.8f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f },
SkColorSpace::kSRGB_Gamut), SkColorSpace::MakeSRGB(), "from1.8");)