1 /*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "GrConfigConversionEffect.h"
9 #include "GrContext.h"
10 #include "GrInvariantOutput.h"
11 #include "GrSimpleTextureEffect.h"
12 #include "SkMatrix.h"
13 #include "gl/GrGLProcessor.h"
14 #include "gl/builders/GrGLProgramBuilder.h"
15
16 class GrGLConfigConversionEffect : public GrGLFragmentProcessor {
17 public:
GrGLConfigConversionEffect(const GrProcessor & processor)18 GrGLConfigConversionEffect(const GrProcessor& processor) {
19 const GrConfigConversionEffect& configConversionEffect =
20 processor.cast<GrConfigConversionEffect>();
21 fSwapRedAndBlue = configConversionEffect.swapsRedAndBlue();
22 fPMConversion = configConversionEffect.pmConversion();
23 }
24
emitCode(GrGLFPBuilder * builder,const GrFragmentProcessor &,const char * outputColor,const char * inputColor,const TransformedCoordsArray & coords,const TextureSamplerArray & samplers)25 virtual void emitCode(GrGLFPBuilder* builder,
26 const GrFragmentProcessor&,
27 const char* outputColor,
28 const char* inputColor,
29 const TransformedCoordsArray& coords,
30 const TextureSamplerArray& samplers) override {
31 // Using highp for GLES here in order to avoid some precision issues on specific GPUs.
32 GrGLShaderVar tmpVar("tmpColor", kVec4f_GrSLType, 0, kHigh_GrSLPrecision);
33 SkString tmpDecl;
34 tmpVar.appendDecl(builder->ctxInfo(), &tmpDecl);
35
36 GrGLFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
37
38 fsBuilder->codeAppendf("%s;", tmpDecl.c_str());
39
40 fsBuilder->codeAppendf("%s = ", tmpVar.c_str());
41 fsBuilder->appendTextureLookup(samplers[0], coords[0].c_str(), coords[0].getType());
42 fsBuilder->codeAppend(";");
43
44 if (GrConfigConversionEffect::kNone_PMConversion == fPMConversion) {
45 SkASSERT(fSwapRedAndBlue);
46 fsBuilder->codeAppendf("%s = %s.bgra;", outputColor, tmpVar.c_str());
47 } else {
48 const char* swiz = fSwapRedAndBlue ? "bgr" : "rgb";
49 switch (fPMConversion) {
50 case GrConfigConversionEffect::kMulByAlpha_RoundUp_PMConversion:
51 fsBuilder->codeAppendf(
52 "%s = vec4(ceil(%s.%s * %s.a * 255.0) / 255.0, %s.a);",
53 tmpVar.c_str(), tmpVar.c_str(), swiz, tmpVar.c_str(), tmpVar.c_str());
54 break;
55 case GrConfigConversionEffect::kMulByAlpha_RoundDown_PMConversion:
56 // Add a compensation(0.001) here to avoid the side effect of the floor operation.
57 // In Intel GPUs, the integer value converted from floor(%s.r * 255.0) / 255.0
58 // is less than the integer value converted from %s.r by 1 when the %s.r is
59 // converted from the integer value 2^n, such as 1, 2, 4, 8, etc.
60 fsBuilder->codeAppendf(
61 "%s = vec4(floor(%s.%s * %s.a * 255.0 + 0.001) / 255.0, %s.a);",
62 tmpVar.c_str(), tmpVar.c_str(), swiz, tmpVar.c_str(), tmpVar.c_str());
63 break;
64 case GrConfigConversionEffect::kDivByAlpha_RoundUp_PMConversion:
65 fsBuilder->codeAppendf(
66 "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(ceil(%s.%s / %s.a * 255.0) / 255.0, %s.a);",
67 tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), swiz, tmpVar.c_str(), tmpVar.c_str());
68 break;
69 case GrConfigConversionEffect::kDivByAlpha_RoundDown_PMConversion:
70 fsBuilder->codeAppendf(
71 "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(floor(%s.%s / %s.a * 255.0) / 255.0, %s.a);",
72 tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), swiz, tmpVar.c_str(), tmpVar.c_str());
73 break;
74 default:
75 SkFAIL("Unknown conversion op.");
76 break;
77 }
78 fsBuilder->codeAppendf("%s = %s;", outputColor, tmpVar.c_str());
79 }
80 SkString modulate;
81 GrGLSLMulVarBy4f(&modulate, outputColor, inputColor);
82 fsBuilder->codeAppend(modulate.c_str());
83 }
84
GenKey(const GrProcessor & processor,const GrGLSLCaps &,GrProcessorKeyBuilder * b)85 static inline void GenKey(const GrProcessor& processor, const GrGLSLCaps&,
86 GrProcessorKeyBuilder* b) {
87 const GrConfigConversionEffect& conv = processor.cast<GrConfigConversionEffect>();
88 uint32_t key = (conv.swapsRedAndBlue() ? 0 : 1) | (conv.pmConversion() << 1);
89 b->add32(key);
90 }
91
92 private:
93 bool fSwapRedAndBlue;
94 GrConfigConversionEffect::PMConversion fPMConversion;
95
96 typedef GrGLFragmentProcessor INHERITED;
97
98 };
99
100 ///////////////////////////////////////////////////////////////////////////////
101
GrConfigConversionEffect(GrTexture * texture,bool swapRedAndBlue,PMConversion pmConversion,const SkMatrix & matrix)102 GrConfigConversionEffect::GrConfigConversionEffect(GrTexture* texture,
103 bool swapRedAndBlue,
104 PMConversion pmConversion,
105 const SkMatrix& matrix)
106 : GrSingleTextureEffect(texture, matrix)
107 , fSwapRedAndBlue(swapRedAndBlue)
108 , fPMConversion(pmConversion) {
109 this->initClassID<GrConfigConversionEffect>();
110 SkASSERT(kRGBA_8888_GrPixelConfig == texture->config() ||
111 kBGRA_8888_GrPixelConfig == texture->config());
112 // Why did we pollute our texture cache instead of using a GrSingleTextureEffect?
113 SkASSERT(swapRedAndBlue || kNone_PMConversion != pmConversion);
114 }
115
onIsEqual(const GrFragmentProcessor & s) const116 bool GrConfigConversionEffect::onIsEqual(const GrFragmentProcessor& s) const {
117 const GrConfigConversionEffect& other = s.cast<GrConfigConversionEffect>();
118 return other.fSwapRedAndBlue == fSwapRedAndBlue &&
119 other.fPMConversion == fPMConversion;
120 }
121
onComputeInvariantOutput(GrInvariantOutput * inout) const122 void GrConfigConversionEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
123 this->updateInvariantOutputForModulation(inout);
124 }
125
126 ///////////////////////////////////////////////////////////////////////////////
127
128 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrConfigConversionEffect);
129
TestCreate(SkRandom * random,GrContext *,const GrDrawTargetCaps &,GrTexture * textures[])130 GrFragmentProcessor* GrConfigConversionEffect::TestCreate(SkRandom* random,
131 GrContext*,
132 const GrDrawTargetCaps&,
133 GrTexture* textures[]) {
134 PMConversion pmConv = static_cast<PMConversion>(random->nextULessThan(kPMConversionCnt));
135 bool swapRB;
136 if (kNone_PMConversion == pmConv) {
137 swapRB = true;
138 } else {
139 swapRB = random->nextBool();
140 }
141 return SkNEW_ARGS(GrConfigConversionEffect,
142 (textures[GrProcessorUnitTest::kSkiaPMTextureIdx],
143 swapRB,
144 pmConv,
145 GrTest::TestMatrix(random)));
146 }
147
148 ///////////////////////////////////////////////////////////////////////////////
149
getGLProcessorKey(const GrGLSLCaps & caps,GrProcessorKeyBuilder * b) const150 void GrConfigConversionEffect::getGLProcessorKey(const GrGLSLCaps& caps,
151 GrProcessorKeyBuilder* b) const {
152 GrGLConfigConversionEffect::GenKey(*this, caps, b);
153 }
154
createGLInstance() const155 GrGLFragmentProcessor* GrConfigConversionEffect::createGLInstance() const {
156 return SkNEW_ARGS(GrGLConfigConversionEffect, (*this));
157 }
158
159
160
TestForPreservingPMConversions(GrContext * context,PMConversion * pmToUPMRule,PMConversion * upmToPMRule)161 void GrConfigConversionEffect::TestForPreservingPMConversions(GrContext* context,
162 PMConversion* pmToUPMRule,
163 PMConversion* upmToPMRule) {
164 *pmToUPMRule = kNone_PMConversion;
165 *upmToPMRule = kNone_PMConversion;
166 SkAutoTMalloc<uint32_t> data(256 * 256 * 3);
167 uint32_t* srcData = data.get();
168 uint32_t* firstRead = data.get() + 256 * 256;
169 uint32_t* secondRead = data.get() + 2 * 256 * 256;
170
171 // Fill with every possible premultiplied A, color channel value. There will be 256-y duplicate
172 // values in row y. We set r,g, and b to the same value since they are handled identically.
173 for (int y = 0; y < 256; ++y) {
174 for (int x = 0; x < 256; ++x) {
175 uint8_t* color = reinterpret_cast<uint8_t*>(&srcData[256*y + x]);
176 color[3] = y;
177 color[2] = SkTMin(x, y);
178 color[1] = SkTMin(x, y);
179 color[0] = SkTMin(x, y);
180 }
181 }
182
183 GrSurfaceDesc desc;
184 desc.fFlags = kRenderTarget_GrSurfaceFlag;
185 desc.fWidth = 256;
186 desc.fHeight = 256;
187 desc.fConfig = kRGBA_8888_GrPixelConfig;
188
189 SkAutoTUnref<GrTexture> readTex(context->textureProvider()->createTexture(desc, true, NULL, 0));
190 if (!readTex.get()) {
191 return;
192 }
193 SkAutoTUnref<GrTexture> tempTex(context->textureProvider()->createTexture(desc, true, NULL, 0));
194 if (!tempTex.get()) {
195 return;
196 }
197 desc.fFlags = kNone_GrSurfaceFlags;
198 SkAutoTUnref<GrTexture> dataTex(context->textureProvider()->createTexture(desc, true, data, 0));
199 if (!dataTex.get()) {
200 return;
201 }
202
203 static const PMConversion kConversionRules[][2] = {
204 {kDivByAlpha_RoundDown_PMConversion, kMulByAlpha_RoundUp_PMConversion},
205 {kDivByAlpha_RoundUp_PMConversion, kMulByAlpha_RoundDown_PMConversion},
206 };
207
208 bool failed = true;
209
210 for (size_t i = 0; i < SK_ARRAY_COUNT(kConversionRules) && failed; ++i) {
211 *pmToUPMRule = kConversionRules[i][0];
212 *upmToPMRule = kConversionRules[i][1];
213
214 static const SkRect kDstRect = SkRect::MakeWH(SkIntToScalar(256), SkIntToScalar(256));
215 static const SkRect kSrcRect = SkRect::MakeWH(SK_Scalar1, SK_Scalar1);
216 // We do a PM->UPM draw from dataTex to readTex and read the data. Then we do a UPM->PM draw
217 // from readTex to tempTex followed by a PM->UPM draw to readTex and finally read the data.
218 // We then verify that two reads produced the same values.
219
220 SkAutoTUnref<GrFragmentProcessor> pmToUPM1(
221 SkNEW_ARGS(GrConfigConversionEffect,
222 (dataTex, false, *pmToUPMRule, SkMatrix::I())));
223 SkAutoTUnref<GrFragmentProcessor> upmToPM(
224 SkNEW_ARGS(GrConfigConversionEffect,
225 (readTex, false, *upmToPMRule, SkMatrix::I())));
226 SkAutoTUnref<GrFragmentProcessor> pmToUPM2(
227 SkNEW_ARGS(GrConfigConversionEffect,
228 (tempTex, false, *pmToUPMRule, SkMatrix::I())));
229
230 GrPaint paint1;
231 paint1.addColorProcessor(pmToUPM1);
232 context->drawNonAARectToRect(readTex->asRenderTarget(),
233 GrClip::WideOpen(),
234 paint1,
235 SkMatrix::I(),
236 kDstRect,
237 kSrcRect);
238
239 readTex->readPixels(0, 0, 256, 256, kRGBA_8888_GrPixelConfig, firstRead);
240
241 GrPaint paint2;
242 paint2.addColorProcessor(upmToPM);
243 context->drawNonAARectToRect(tempTex->asRenderTarget(),
244 GrClip::WideOpen(),
245 paint2,
246 SkMatrix::I(),
247 kDstRect,
248 kSrcRect);
249
250 GrPaint paint3;
251 paint3.addColorProcessor(pmToUPM2);
252 context->drawNonAARectToRect(readTex->asRenderTarget(),
253 GrClip::WideOpen(),
254 paint3,
255 SkMatrix::I(),
256 kDstRect,
257 kSrcRect);
258
259 readTex->readPixels(0, 0, 256, 256, kRGBA_8888_GrPixelConfig, secondRead);
260
261 failed = false;
262 for (int y = 0; y < 256 && !failed; ++y) {
263 for (int x = 0; x <= y; ++x) {
264 if (firstRead[256 * y + x] != secondRead[256 * y + x]) {
265 failed = true;
266 break;
267 }
268 }
269 }
270 }
271 if (failed) {
272 *pmToUPMRule = kNone_PMConversion;
273 *upmToPMRule = kNone_PMConversion;
274 }
275 }
276
Create(GrTexture * texture,bool swapRedAndBlue,PMConversion pmConversion,const SkMatrix & matrix)277 const GrFragmentProcessor* GrConfigConversionEffect::Create(GrTexture* texture,
278 bool swapRedAndBlue,
279 PMConversion pmConversion,
280 const SkMatrix& matrix) {
281 if (!swapRedAndBlue && kNone_PMConversion == pmConversion) {
282 // If we returned a GrConfigConversionEffect that was equivalent to a GrSimpleTextureEffect
283 // then we may pollute our texture cache with redundant shaders. So in the case that no
284 // conversions were requested we instead return a GrSimpleTextureEffect.
285 return GrSimpleTextureEffect::Create(texture, matrix);
286 } else {
287 if (kRGBA_8888_GrPixelConfig != texture->config() &&
288 kBGRA_8888_GrPixelConfig != texture->config() &&
289 kNone_PMConversion != pmConversion) {
290 // The PM conversions assume colors are 0..255
291 return NULL;
292 }
293 return SkNEW_ARGS(GrConfigConversionEffect, (texture,
294 swapRedAndBlue,
295 pmConversion,
296 matrix));
297 }
298 }
299