2 * Copyright 2013 Google Inc.
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
8 #include "SkAlphaThresholdFilter.h"
11 #include "SkReadBuffer.h"
12 #include "SkWriteBuffer.h"
15 #include "GrDrawContext.h"
18 class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter {
20 SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold,
21 SkScalar outerThreshold, SkImageFilter* input);
23 SK_TO_STRING_OVERRIDE()
24 SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
27 void flatten(SkWriteBuffer&) const override;
29 bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
30 SkBitmap* result, SkIPoint* offset) const override;
32 bool asFragmentProcessor(GrFragmentProcessor**, GrTexture*, const SkMatrix&,
33 const SkIRect& bounds) const override;
38 SkScalar fInnerThreshold;
39 SkScalar fOuterThreshold;
40 typedef SkImageFilter INHERITED;
43 SkImageFilter* SkAlphaThresholdFilter::Create(const SkRegion& region,
44 SkScalar innerThreshold,
45 SkScalar outerThreshold,
46 SkImageFilter* input) {
47 return new SkAlphaThresholdFilterImpl(region, innerThreshold, outerThreshold, input);
51 #include "GrContext.h"
52 #include "GrCoordTransform.h"
53 #include "GrFragmentProcessor.h"
54 #include "GrInvariantOutput.h"
55 #include "GrTextureAccess.h"
56 #include "effects/GrPorterDuffXferProcessor.h"
60 #include "glsl/GrGLSLFragmentProcessor.h"
61 #include "glsl/GrGLSLFragmentShaderBuilder.h"
62 #include "glsl/GrGLSLProgramBuilder.h"
63 #include "glsl/GrGLSLProgramDataManager.h"
65 class AlphaThresholdEffect : public GrFragmentProcessor {
68 static GrFragmentProcessor* Create(GrTexture* texture,
69 GrTexture* maskTexture,
71 float outerThreshold) {
72 return new AlphaThresholdEffect(texture, maskTexture, innerThreshold, outerThreshold);
75 virtual ~AlphaThresholdEffect() {};
77 const char* name() const override { return "Alpha Threshold"; }
79 float innerThreshold() const { return fInnerThreshold; }
80 float outerThreshold() const { return fOuterThreshold; }
83 AlphaThresholdEffect(GrTexture* texture,
84 GrTexture* maskTexture,
87 : fInnerThreshold(innerThreshold)
88 , fOuterThreshold(outerThreshold)
89 , fImageCoordTransform(kLocal_GrCoordSet,
90 GrCoordTransform::MakeDivByTextureWHMatrix(texture), texture,
91 GrTextureParams::kNone_FilterMode)
92 , fImageTextureAccess(texture)
93 , fMaskCoordTransform(kLocal_GrCoordSet,
94 GrCoordTransform::MakeDivByTextureWHMatrix(maskTexture), maskTexture,
95 GrTextureParams::kNone_FilterMode)
96 , fMaskTextureAccess(maskTexture) {
97 this->initClassID<AlphaThresholdEffect>();
98 this->addCoordTransform(&fImageCoordTransform);
99 this->addTextureAccess(&fImageTextureAccess);
100 this->addCoordTransform(&fMaskCoordTransform);
101 this->addTextureAccess(&fMaskTextureAccess);
104 GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
106 void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
108 bool onIsEqual(const GrFragmentProcessor&) const override;
110 void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
112 GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
114 float fInnerThreshold;
115 float fOuterThreshold;
116 GrCoordTransform fImageCoordTransform;
117 GrTextureAccess fImageTextureAccess;
118 GrCoordTransform fMaskCoordTransform;
119 GrTextureAccess fMaskTextureAccess;
121 typedef GrFragmentProcessor INHERITED;
124 class GrGLAlphaThresholdEffect : public GrGLSLFragmentProcessor {
126 GrGLAlphaThresholdEffect(const GrFragmentProcessor&) {}
128 virtual void emitCode(EmitArgs&) override;
131 void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override;
135 GrGLSLProgramDataManager::UniformHandle fInnerThresholdVar;
136 GrGLSLProgramDataManager::UniformHandle fOuterThresholdVar;
138 typedef GrGLSLFragmentProcessor INHERITED;
141 void GrGLAlphaThresholdEffect::emitCode(EmitArgs& args) {
142 fInnerThresholdVar = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
143 kFloat_GrSLType, kDefault_GrSLPrecision,
145 fOuterThresholdVar = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
146 kFloat_GrSLType, kDefault_GrSLPrecision,
149 GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
150 SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
151 SkString maskCoords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 1);
153 fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
154 fragBuilder->codeAppendf("\t\tvec2 mask_coord = %s;\n", maskCoords2D.c_str());
155 fragBuilder->codeAppend("\t\tvec4 input_color = ");
156 fragBuilder->appendTextureLookup(args.fSamplers[0], "coord");
157 fragBuilder->codeAppend(";\n");
158 fragBuilder->codeAppend("\t\tvec4 mask_color = ");
159 fragBuilder->appendTextureLookup(args.fSamplers[1], "mask_coord");
160 fragBuilder->codeAppend(";\n");
162 fragBuilder->codeAppendf("\t\tfloat inner_thresh = %s;\n",
163 args.fBuilder->getUniformCStr(fInnerThresholdVar));
164 fragBuilder->codeAppendf("\t\tfloat outer_thresh = %s;\n",
165 args.fBuilder->getUniformCStr(fOuterThresholdVar));
166 fragBuilder->codeAppend("\t\tfloat mask = mask_color.a;\n");
168 fragBuilder->codeAppend("vec4 color = input_color;\n");
169 fragBuilder->codeAppend("\t\tif (mask < 0.5) {\n"
170 "\t\t\tif (color.a > outer_thresh) {\n"
171 "\t\t\t\tfloat scale = outer_thresh / color.a;\n"
172 "\t\t\t\tcolor.rgb *= scale;\n"
173 "\t\t\t\tcolor.a = outer_thresh;\n"
175 "\t\t} else if (color.a < inner_thresh) {\n"
176 "\t\t\tfloat scale = inner_thresh / max(0.001, color.a);\n"
177 "\t\t\tcolor.rgb *= scale;\n"
178 "\t\t\tcolor.a = inner_thresh;\n"
181 fragBuilder->codeAppendf("%s = %s;\n", args.fOutputColor,
182 (GrGLSLExpr4(args.fInputColor) * GrGLSLExpr4("color")).c_str());
185 void GrGLAlphaThresholdEffect::onSetData(const GrGLSLProgramDataManager& pdman,
186 const GrProcessor& proc) {
187 const AlphaThresholdEffect& alpha_threshold = proc.cast<AlphaThresholdEffect>();
188 pdman.set1f(fInnerThresholdVar, alpha_threshold.innerThreshold());
189 pdman.set1f(fOuterThresholdVar, alpha_threshold.outerThreshold());
192 /////////////////////////////////////////////////////////////////////
194 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(AlphaThresholdEffect);
196 const GrFragmentProcessor* AlphaThresholdEffect::TestCreate(GrProcessorTestData* d) {
197 GrTexture* bmpTex = d->fTextures[GrProcessorUnitTest::kSkiaPMTextureIdx];
198 GrTexture* maskTex = d->fTextures[GrProcessorUnitTest::kAlphaTextureIdx];
199 float innerThresh = d->fRandom->nextUScalar1();
200 float outerThresh = d->fRandom->nextUScalar1();
201 return AlphaThresholdEffect::Create(bmpTex, maskTex, innerThresh, outerThresh);
204 ///////////////////////////////////////////////////////////////////////////////
206 void AlphaThresholdEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
207 GrProcessorKeyBuilder* b) const {
208 GrGLAlphaThresholdEffect::GenKey(*this, caps, b);
211 GrGLSLFragmentProcessor* AlphaThresholdEffect::onCreateGLSLInstance() const {
212 return new GrGLAlphaThresholdEffect(*this);
215 bool AlphaThresholdEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
216 const AlphaThresholdEffect& s = sBase.cast<AlphaThresholdEffect>();
217 return (this->fInnerThreshold == s.fInnerThreshold &&
218 this->fOuterThreshold == s.fOuterThreshold);
221 void AlphaThresholdEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
222 if (GrPixelConfigIsAlphaOnly(this->texture(0)->config())) {
223 inout->mulByUnknownSingleComponent();
224 } else if (GrPixelConfigIsOpaque(this->texture(0)->config()) && fOuterThreshold >= 1.f) {
225 inout->mulByUnknownOpaqueFourComponents();
227 inout->mulByUnknownFourComponents();
233 SkFlattenable* SkAlphaThresholdFilterImpl::CreateProc(SkReadBuffer& buffer) {
234 SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
235 SkScalar inner = buffer.readScalar();
236 SkScalar outer = buffer.readScalar();
238 buffer.readRegion(&rgn);
239 return SkAlphaThresholdFilter::Create(rgn, inner, outer, common.getInput(0));
242 SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(const SkRegion& region,
243 SkScalar innerThreshold,
244 SkScalar outerThreshold,
245 SkImageFilter* input)
246 : INHERITED(1, &input)
248 , fInnerThreshold(innerThreshold)
249 , fOuterThreshold(outerThreshold) {
253 bool SkAlphaThresholdFilterImpl::asFragmentProcessor(GrFragmentProcessor** fp,
255 const SkMatrix& inMatrix,
256 const SkIRect&) const {
258 GrContext* context = texture->getContext();
259 GrSurfaceDesc maskDesc;
260 if (context->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
261 maskDesc.fConfig = kAlpha_8_GrPixelConfig;
263 maskDesc.fConfig = kRGBA_8888_GrPixelConfig;
265 maskDesc.fFlags = kRenderTarget_GrSurfaceFlag;
266 // Add one pixel of border to ensure that clamp mode will be all zeros
268 maskDesc.fWidth = texture->width();
269 maskDesc.fHeight = texture->height();
270 SkAutoTUnref<GrTexture> maskTexture(
271 context->textureProvider()->createApproxTexture(maskDesc));
276 SkAutoTUnref<GrDrawContext> drawContext(
277 context->drawContext(maskTexture->asRenderTarget()));
280 grPaint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
281 SkRegion::Iterator iter(fRegion);
282 drawContext->clear(nullptr, 0x0, true);
284 while (!iter.done()) {
285 SkRect rect = SkRect::Make(iter.rect());
286 drawContext->drawRect(GrClip::WideOpen(), grPaint, inMatrix, rect);
291 *fp = AlphaThresholdEffect::Create(texture,
300 void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const {
301 this->INHERITED::flatten(buffer);
302 buffer.writeScalar(fInnerThreshold);
303 buffer.writeScalar(fOuterThreshold);
304 buffer.writeRegion(fRegion);
307 bool SkAlphaThresholdFilterImpl::onFilterImage(Proxy* proxy, const SkBitmap& src,
308 const Context& ctx, SkBitmap* dst,
309 SkIPoint* offset) const {
310 SkASSERT(src.colorType() == kN32_SkColorType);
312 if (src.colorType() != kN32_SkColorType) {
316 SkMatrix localInverse;
317 if (!ctx.ctm().invert(&localInverse)) {
321 SkAutoLockPixels alp(src);
322 SkASSERT(src.getPixels());
323 if (!src.getPixels() || src.width() <= 0 || src.height() <= 0) {
327 SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(src.width(), src.height()));
331 *dst = device->accessBitmap(false);
332 SkAutoLockPixels alp_dst(*dst);
334 U8CPU innerThreshold = (U8CPU)(fInnerThreshold * 0xFF);
335 U8CPU outerThreshold = (U8CPU)(fOuterThreshold * 0xFF);
336 SkColor* sptr = src.getAddr32(0, 0);
337 SkColor* dptr = dst->getAddr32(0, 0);
338 int width = src.width(), height = src.height();
339 for (int y = 0; y < height; ++y) {
340 for (int x = 0; x < width; ++x) {
341 const SkColor& source = sptr[y * width + x];
342 SkColor output_color(source);
344 localInverse.mapXY((SkScalar)x, (SkScalar)y, &position);
345 if (fRegion.contains((int32_t)position.x(), (int32_t)position.y())) {
346 if (SkColorGetA(source) < innerThreshold) {
347 U8CPU alpha = SkColorGetA(source);
350 float scale = (float)innerThreshold / alpha;
351 output_color = SkColorSetARGB(innerThreshold,
352 (U8CPU)(SkColorGetR(source) * scale),
353 (U8CPU)(SkColorGetG(source) * scale),
354 (U8CPU)(SkColorGetB(source) * scale));
357 if (SkColorGetA(source) > outerThreshold) {
358 float scale = (float)outerThreshold / SkColorGetA(source);
359 output_color = SkColorSetARGB(outerThreshold,
360 (U8CPU)(SkColorGetR(source) * scale),
361 (U8CPU)(SkColorGetG(source) * scale),
362 (U8CPU)(SkColorGetB(source) * scale));
365 dptr[y * dst->width() + x] = output_color;
372 #ifndef SK_IGNORE_TO_STRING
373 void SkAlphaThresholdFilterImpl::toString(SkString* str) const {
374 str->appendf("SkAlphaThresholdImageFilter: (");
375 str->appendf("inner: %f outer: %f", fInnerThreshold, fOuterThreshold);