/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "GrConfigConversionEffect.h"
#include "GrContext.h"
#include "GrDrawContext.h"
#include "GrInvariantOutput.h"
#include "GrSimpleTextureEffect.h"
#include "SkMatrix.h"
#include "glsl/GrGLSLFragmentProcessor.h"
#include "glsl/GrGLSLFragmentShaderBuilder.h"
class GrGLConfigConversionEffect : public GrGLSLFragmentProcessor {
public:
void emitCode(EmitArgs& args) override {
const GrConfigConversionEffect& cce = args.fFp.cast<GrConfigConversionEffect>();
const GrSwizzle& swizzle = cce.swizzle();
GrConfigConversionEffect::PMConversion pmConversion = cce.pmConversion();
// Using highp for GLES here in order to avoid some precision issues on specific GPUs.
GrGLSLShaderVar tmpVar("tmpColor", kVec4f_GrSLType, 0, kHigh_GrSLPrecision);
SkString tmpDecl;
tmpVar.appendDecl(args.fGLSLCaps, &tmpDecl);
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
fragBuilder->codeAppendf("%s;", tmpDecl.c_str());
fragBuilder->codeAppendf("%s = ", tmpVar.c_str());
fragBuilder->appendTextureLookup(args.fSamplers[0], args.fCoords[0].c_str(),
args.fCoords[0].getType());
fragBuilder->codeAppend(";");
if (GrConfigConversionEffect::kNone_PMConversion == pmConversion) {
SkASSERT(GrSwizzle::RGBA() != swizzle);
fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
swizzle.c_str());
} else {
switch (pmConversion) {
case GrConfigConversionEffect::kMulByAlpha_RoundUp_PMConversion:
fragBuilder->codeAppendf(
"%s = vec4(ceil(%s.rgb * %s.a * 255.0) / 255.0, %s.a);",
tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());
break;
case GrConfigConversionEffect::kMulByAlpha_RoundDown_PMConversion:
// Add a compensation(0.001) here to avoid the side effect of the floor operation.
// In Intel GPUs, the integer value converted from floor(%s.r * 255.0) / 255.0
// is less than the integer value converted from %s.r by 1 when the %s.r is
// converted from the integer value 2^n, such as 1, 2, 4, 8, etc.
fragBuilder->codeAppendf(
"%s = vec4(floor(%s.rgb * %s.a * 255.0 + 0.001) / 255.0, %s.a);",
tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());
break;
case GrConfigConversionEffect::kDivByAlpha_RoundUp_PMConversion:
fragBuilder->codeAppendf(
"%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(ceil(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
tmpVar.c_str());
break;
case GrConfigConversionEffect::kDivByAlpha_RoundDown_PMConversion:
fragBuilder->codeAppendf(
"%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(floor(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
tmpVar.c_str());
break;
default:
SkFAIL("Unknown conversion op.");
break;
}
fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
swizzle.c_str());
}
SkString modulate;
GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
fragBuilder->codeAppend(modulate.c_str());
}
static inline void GenKey(const GrProcessor& processor, const GrGLSLCaps&,
GrProcessorKeyBuilder* b) {
const GrConfigConversionEffect& cce = processor.cast<GrConfigConversionEffect>();
uint32_t key = (cce.swizzle().asKey()) | (cce.pmConversion() << 16);
b->add32(key);
}
private:
typedef GrGLSLFragmentProcessor INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
GrConfigConversionEffect::GrConfigConversionEffect(GrTexture* texture,
const GrSwizzle& swizzle,
PMConversion pmConversion,
const SkMatrix& matrix)
: INHERITED(texture, matrix)
, fSwizzle(swizzle)
, fPMConversion(pmConversion) {
this->initClassID<GrConfigConversionEffect>();
// We expect to get here with non-BGRA/RGBA only if we're doing not doing a premul/unpremul
// conversion.
SkASSERT((kRGBA_8888_GrPixelConfig == texture->config() ||
kBGRA_8888_GrPixelConfig == texture->config()) ||
kNone_PMConversion == pmConversion);
// Why did we pollute our texture cache instead of using a GrSingleTextureEffect?
SkASSERT(swizzle != GrSwizzle::RGBA() || kNone_PMConversion != pmConversion);
}
bool GrConfigConversionEffect::onIsEqual(const GrFragmentProcessor& s) const {
const GrConfigConversionEffect& other = s.cast<GrConfigConversionEffect>();
return other.fSwizzle == fSwizzle &&
other.fPMConversion == fPMConversion;
}
void GrConfigConversionEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
this->updateInvariantOutputForModulation(inout);
}
///////////////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrConfigConversionEffect);
const GrFragmentProcessor* GrConfigConversionEffect::TestCreate(GrProcessorTestData* d) {
PMConversion pmConv = static_cast<PMConversion>(d->fRandom->nextULessThan(kPMConversionCnt));
GrSwizzle swizzle;
do {
swizzle = GrSwizzle::CreateRandom(d->fRandom);
} while (pmConv == kNone_PMConversion && swizzle == GrSwizzle::RGBA());
return new GrConfigConversionEffect(d->fTextures[GrProcessorUnitTest::kSkiaPMTextureIdx],
swizzle, pmConv, GrTest::TestMatrix(d->fRandom));
}
///////////////////////////////////////////////////////////////////////////////
void GrConfigConversionEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
GrProcessorKeyBuilder* b) const {
GrGLConfigConversionEffect::GenKey(*this, caps, b);
}
GrGLSLFragmentProcessor* GrConfigConversionEffect::onCreateGLSLInstance() const {
return new GrGLConfigConversionEffect();
}
void GrConfigConversionEffect::TestForPreservingPMConversions(GrContext* context,
PMConversion* pmToUPMRule,
PMConversion* upmToPMRule) {
*pmToUPMRule = kNone_PMConversion;
*upmToPMRule = kNone_PMConversion;
SkAutoTMalloc<uint32_t> data(256 * 256 * 3);
uint32_t* srcData = data.get();
uint32_t* firstRead = data.get() + 256 * 256;
uint32_t* secondRead = data.get() + 2 * 256 * 256;
// Fill with every possible premultiplied A, color channel value. There will be 256-y duplicate
// values in row y. We set r,g, and b to the same value since they are handled identically.
for (int y = 0; y < 256; ++y) {
for (int x = 0; x < 256; ++x) {
uint8_t* color = reinterpret_cast<uint8_t*>(&srcData[256*y + x]);
color[3] = y;
color[2] = SkTMin(x, y);
color[1] = SkTMin(x, y);
color[0] = SkTMin(x, y);
}
}
GrSurfaceDesc desc;
desc.fFlags = kRenderTarget_GrSurfaceFlag;
desc.fWidth = 256;
desc.fHeight = 256;
desc.fConfig = kRGBA_8888_GrPixelConfig;
SkAutoTUnref<GrTexture> readTex(context->textureProvider()->createTexture(
desc, SkBudgeted::kYes, nullptr, 0));
if (!readTex.get()) {
return;
}
SkAutoTUnref<GrTexture> tempTex(context->textureProvider()->createTexture(
desc, SkBudgeted::kYes, nullptr, 0));
if (!tempTex.get()) {
return;
}
desc.fFlags = kNone_GrSurfaceFlags;
SkAutoTUnref<GrTexture> dataTex(context->textureProvider()->createTexture(
desc, SkBudgeted::kYes, data, 0));
if (!dataTex.get()) {
return;
}
static const PMConversion kConversionRules[][2] = {
{kDivByAlpha_RoundDown_PMConversion, kMulByAlpha_RoundUp_PMConversion},
{kDivByAlpha_RoundUp_PMConversion, kMulByAlpha_RoundDown_PMConversion},
};
bool failed = true;
for (size_t i = 0; i < SK_ARRAY_COUNT(kConversionRules) && failed; ++i) {
*pmToUPMRule = kConversionRules[i][0];
*upmToPMRule = kConversionRules[i][1];
static const SkRect kDstRect = SkRect::MakeWH(SkIntToScalar(256), SkIntToScalar(256));
static const SkRect kSrcRect = SkRect::MakeWH(SK_Scalar1, SK_Scalar1);
// We do a PM->UPM draw from dataTex to readTex and read the data. Then we do a UPM->PM draw
// from readTex to tempTex followed by a PM->UPM draw to readTex and finally read the data.
// We then verify that two reads produced the same values.
GrPaint paint1;
GrPaint paint2;
GrPaint paint3;
SkAutoTUnref<GrFragmentProcessor> pmToUPM1(new GrConfigConversionEffect(
dataTex, GrSwizzle::RGBA(), *pmToUPMRule, SkMatrix::I()));
SkAutoTUnref<GrFragmentProcessor> upmToPM(new GrConfigConversionEffect(
readTex, GrSwizzle::RGBA(), *upmToPMRule, SkMatrix::I()));
SkAutoTUnref<GrFragmentProcessor> pmToUPM2(new GrConfigConversionEffect(
tempTex, GrSwizzle::RGBA(), *pmToUPMRule, SkMatrix::I()));
paint1.addColorFragmentProcessor(pmToUPM1);
paint1.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
SkAutoTUnref<GrDrawContext> readDrawContext(
context->drawContext(readTex->asRenderTarget()));
if (!readDrawContext) {
failed = true;
break;
}
readDrawContext->fillRectToRect(GrClip::WideOpen(),
paint1,
SkMatrix::I(),
kDstRect,
kSrcRect);
readTex->readPixels(0, 0, 256, 256, kRGBA_8888_GrPixelConfig, firstRead);
paint2.addColorFragmentProcessor(upmToPM);
paint2.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
SkAutoTUnref<GrDrawContext> tempDrawContext(
context->drawContext(tempTex->asRenderTarget()));
if (!tempDrawContext) {
failed = true;
break;
}
tempDrawContext->fillRectToRect(GrClip::WideOpen(),
paint2,
SkMatrix::I(),
kDstRect,
kSrcRect);
paint3.addColorFragmentProcessor(pmToUPM2);
paint3.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
readDrawContext.reset(context->drawContext(readTex->asRenderTarget()));
if (!readDrawContext) {
failed = true;
break;
}
readDrawContext->fillRectToRect(GrClip::WideOpen(),
paint3,
SkMatrix::I(),
kDstRect,
kSrcRect);
readTex->readPixels(0, 0, 256, 256, kRGBA_8888_GrPixelConfig, secondRead);
failed = false;
for (int y = 0; y < 256 && !failed; ++y) {
for (int x = 0; x <= y; ++x) {
if (firstRead[256 * y + x] != secondRead[256 * y + x]) {
failed = true;
break;
}
}
}
}
if (failed) {
*pmToUPMRule = kNone_PMConversion;
*upmToPMRule = kNone_PMConversion;
}
}
const GrFragmentProcessor* GrConfigConversionEffect::Create(GrTexture* texture,
const GrSwizzle& swizzle,
PMConversion pmConversion,
const SkMatrix& matrix) {
if (swizzle == GrSwizzle::RGBA() && kNone_PMConversion == pmConversion) {
// If we returned a GrConfigConversionEffect that was equivalent to a GrSimpleTextureEffect
// then we may pollute our texture cache with redundant shaders. So in the case that no
// conversions were requested we instead return a GrSimpleTextureEffect.
return GrSimpleTextureEffect::Create(texture, matrix);
} else {
if (kRGBA_8888_GrPixelConfig != texture->config() &&
kBGRA_8888_GrPixelConfig != texture->config() &&
kNone_PMConversion != pmConversion) {
// The PM conversions assume colors are 0..255
return nullptr;
}
return new GrConfigConversionEffect(texture, swizzle, pmConversion, matrix);
}
}