1 /*
2 * Copyright 2012 The Android Open Source Project
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 "SkMagnifierImageFilter.h"
9
10 #include "SkBitmap.h"
11 #include "SkColorPriv.h"
12 #include "SkColorSpaceXformer.h"
13 #include "SkReadBuffer.h"
14 #include "SkSpecialImage.h"
15 #include "SkWriteBuffer.h"
16 #include "SkValidationUtils.h"
17
18 ////////////////////////////////////////////////////////////////////////////////
19 #if SK_SUPPORT_GPU
20 #include "GrContext.h"
21 #include "GrTexture.h"
22 #include "effects/GrProxyMove.h"
23 #include "effects/GrSingleTextureEffect.h"
24 #include "glsl/GrGLSLColorSpaceXformHelper.h"
25 #include "glsl/GrGLSLFragmentProcessor.h"
26 #include "glsl/GrGLSLFragmentShaderBuilder.h"
27 #include "glsl/GrGLSLProgramDataManager.h"
28 #include "glsl/GrGLSLUniformHandler.h"
29 #include "../private/GrGLSL.h"
30 #endif
31
Make(const SkRect & srcRect,SkScalar inset,sk_sp<SkImageFilter> input,const CropRect * cropRect)32 sk_sp<SkImageFilter> SkMagnifierImageFilter::Make(const SkRect& srcRect, SkScalar inset,
33 sk_sp<SkImageFilter> input,
34 const CropRect* cropRect) {
35 if (!SkScalarIsFinite(inset) || !SkIsValidRect(srcRect)) {
36 return nullptr;
37 }
38 if (inset < 0) {
39 return nullptr;
40 }
41 // Negative numbers in src rect are not supported
42 if (srcRect.fLeft < 0 || srcRect.fTop < 0) {
43 return nullptr;
44 }
45 return sk_sp<SkImageFilter>(new SkMagnifierImageFilter(srcRect, inset,
46 std::move(input),
47 cropRect));
48 }
49
50 #if SK_SUPPORT_GPU
51 class GrMagnifierEffect : public GrSingleTextureEffect {
52 public:
Make(sk_sp<GrTextureProxy> proxy,sk_sp<GrColorSpaceXform> colorSpaceXform,const SkIRect & bounds,const SkRect & srcRect,float xInvZoom,float yInvZoom,float xInvInset,float yInvInset)53 static sk_sp<GrFragmentProcessor> Make(sk_sp<GrTextureProxy> proxy,
54 sk_sp<GrColorSpaceXform> colorSpaceXform,
55 const SkIRect& bounds,
56 const SkRect& srcRect,
57 float xInvZoom,
58 float yInvZoom,
59 float xInvInset,
60 float yInvInset) {
61 return sk_sp<GrFragmentProcessor>(new GrMagnifierEffect(std::move(proxy),
62 std::move(colorSpaceXform),
63 bounds, srcRect,
64 xInvZoom, yInvZoom,
65 xInvInset, yInvInset));
66 }
67
~GrMagnifierEffect()68 ~GrMagnifierEffect() override {}
69
name() const70 const char* name() const override { return "Magnifier"; }
71
bounds() const72 const SkIRect& bounds() const { return fBounds; } // Bounds of source image.
srcRect() const73 const SkRect& srcRect() const { return fSrcRect; }
74
75 // Scale to apply to zoomed pixels (srcRect size / bounds size).
xInvZoom() const76 float xInvZoom() const { return fXInvZoom; }
yInvZoom() const77 float yInvZoom() const { return fYInvZoom; }
78
79 // 1/radius over which to transition from unzoomed to zoomed pixels (bounds size / inset).
xInvInset() const80 float xInvInset() const { return fXInvInset; }
yInvInset() const81 float yInvInset() const { return fYInvInset; }
82
83 private:
GrMagnifierEffect(sk_sp<GrTextureProxy> proxy,sk_sp<GrColorSpaceXform> colorSpaceXform,const SkIRect & bounds,const SkRect & srcRect,float xInvZoom,float yInvZoom,float xInvInset,float yInvInset)84 GrMagnifierEffect(sk_sp<GrTextureProxy> proxy,
85 sk_sp<GrColorSpaceXform> colorSpaceXform,
86 const SkIRect& bounds,
87 const SkRect& srcRect,
88 float xInvZoom,
89 float yInvZoom,
90 float xInvInset,
91 float yInvInset)
92 : INHERITED{ModulationFlags(proxy->config()),
93 GR_PROXY_MOVE(proxy),
94 std::move(colorSpaceXform),
95 SkMatrix::I()} // TODO: no GrSamplerParams::kBilerp_FilterMode?
96 , fBounds(bounds)
97 , fSrcRect(srcRect)
98 , fXInvZoom(xInvZoom)
99 , fYInvZoom(yInvZoom)
100 , fXInvInset(xInvInset)
101 , fYInvInset(yInvInset) {
102 this->initClassID<GrMagnifierEffect>();
103 }
104
105 GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
106
107 void onGetGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder*) const override;
108
109 bool onIsEqual(const GrFragmentProcessor&) const override;
110
111 GR_DECLARE_FRAGMENT_PROCESSOR_TEST
112
113 SkIRect fBounds;
114 SkRect fSrcRect;
115 float fXInvZoom;
116 float fYInvZoom;
117 float fXInvInset;
118 float fYInvInset;
119
120 typedef GrSingleTextureEffect INHERITED;
121 };
122
123 // For brevity
124 typedef GrGLSLProgramDataManager::UniformHandle UniformHandle;
125
126 class GrGLMagnifierEffect : public GrGLSLFragmentProcessor {
127 public:
128 void emitCode(EmitArgs&) override;
129
GenKey(const GrProcessor & effect,const GrShaderCaps &,GrProcessorKeyBuilder * b)130 static inline void GenKey(const GrProcessor& effect, const GrShaderCaps&,
131 GrProcessorKeyBuilder* b) {
132 const GrMagnifierEffect& zoom = effect.cast<GrMagnifierEffect>();
133 b->add32(GrColorSpaceXform::XformKey(zoom.colorSpaceXform()));
134 }
135
136 protected:
137 void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override;
138
139 private:
140 UniformHandle fOffsetVar;
141 UniformHandle fInvZoomVar;
142 UniformHandle fInvInsetVar;
143 UniformHandle fBoundsVar;
144 GrGLSLColorSpaceXformHelper fColorSpaceHelper;
145
146 typedef GrGLSLFragmentProcessor INHERITED;
147 };
148
emitCode(EmitArgs & args)149 void GrGLMagnifierEffect::emitCode(EmitArgs& args) {
150 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
151 fOffsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
152 kVec2f_GrSLType, kDefault_GrSLPrecision,
153 "Offset");
154 fInvZoomVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
155 kVec2f_GrSLType, kDefault_GrSLPrecision,
156 "InvZoom");
157 fInvInsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
158 kVec2f_GrSLType, kDefault_GrSLPrecision,
159 "InvInset");
160 fBoundsVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
161 kVec4f_GrSLType, kDefault_GrSLPrecision,
162 "Bounds");
163
164 const GrMagnifierEffect& zoom = args.fFp.cast<GrMagnifierEffect>();
165 fColorSpaceHelper.emitCode(uniformHandler, zoom.colorSpaceXform());
166
167 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
168 SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);
169 fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
170 fragBuilder->codeAppendf("\t\tvec2 zoom_coord = %s + %s * %s;\n",
171 uniformHandler->getUniformCStr(fOffsetVar),
172 coords2D.c_str(),
173 uniformHandler->getUniformCStr(fInvZoomVar));
174 const char* bounds = uniformHandler->getUniformCStr(fBoundsVar);
175 fragBuilder->codeAppendf("\t\tvec2 delta = (coord - %s.xy) * %s.zw;\n", bounds, bounds);
176 fragBuilder->codeAppendf("\t\tdelta = min(delta, vec2(1.0, 1.0) - delta);\n");
177 fragBuilder->codeAppendf("\t\tdelta = delta * %s;\n",
178 uniformHandler->getUniformCStr(fInvInsetVar));
179
180 fragBuilder->codeAppend("\t\tfloat weight = 0.0;\n");
181 fragBuilder->codeAppend("\t\tif (delta.s < 2.0 && delta.t < 2.0) {\n");
182 fragBuilder->codeAppend("\t\t\tdelta = vec2(2.0, 2.0) - delta;\n");
183 fragBuilder->codeAppend("\t\t\tfloat dist = length(delta);\n");
184 fragBuilder->codeAppend("\t\t\tdist = max(2.0 - dist, 0.0);\n");
185 fragBuilder->codeAppend("\t\t\tweight = min(dist * dist, 1.0);\n");
186 fragBuilder->codeAppend("\t\t} else {\n");
187 fragBuilder->codeAppend("\t\t\tvec2 delta_squared = delta * delta;\n");
188 fragBuilder->codeAppend("\t\t\tweight = min(min(delta_squared.x, delta_squared.y), 1.0);\n");
189 fragBuilder->codeAppend("\t\t}\n");
190
191 fragBuilder->codeAppend("\t\tvec2 mix_coord = mix(coord, zoom_coord, weight);\n");
192 fragBuilder->codeAppend("\t\tvec4 output_color = ");
193 fragBuilder->appendTextureLookup(args.fTexSamplers[0], "mix_coord", kVec2f_GrSLType,
194 &fColorSpaceHelper);
195 fragBuilder->codeAppend(";\n");
196
197 fragBuilder->codeAppendf("\t\t%s = output_color;\n", args.fOutputColor);
198 fragBuilder->codeAppendf("%s *= %s;\n", args.fOutputColor, args.fInputColor);
199 }
200
onSetData(const GrGLSLProgramDataManager & pdman,const GrFragmentProcessor & effect)201 void GrGLMagnifierEffect::onSetData(const GrGLSLProgramDataManager& pdman,
202 const GrFragmentProcessor& effect) {
203 const GrMagnifierEffect& zoom = effect.cast<GrMagnifierEffect>();
204
205 GrTexture* tex = zoom.textureSampler(0).peekTexture();
206
207 SkScalar invW = 1.0f / tex->width();
208 SkScalar invH = 1.0f / tex->height();
209
210 {
211 SkScalar y = zoom.srcRect().y() * invH;
212 if (tex->origin() != kTopLeft_GrSurfaceOrigin) {
213 y = 1.0f - (zoom.srcRect().height() / zoom.bounds().height()) - y;
214 }
215
216 pdman.set2f(fOffsetVar, zoom.srcRect().x() * invW, y);
217 }
218
219 pdman.set2f(fInvZoomVar, zoom.xInvZoom(), zoom.yInvZoom());
220 pdman.set2f(fInvInsetVar, zoom.xInvInset(), zoom.yInvInset());
221
222 {
223 SkScalar y = zoom.bounds().y() * invH;
224 if (tex->origin() != kTopLeft_GrSurfaceOrigin) {
225 y = 1.0f - zoom.bounds().height() * invH;
226 }
227
228 pdman.set4f(fBoundsVar,
229 zoom.bounds().x() * invW,
230 y,
231 SkIntToScalar(tex->width()) / zoom.bounds().width(),
232 SkIntToScalar(tex->height()) / zoom.bounds().height());
233 }
234
235 if (SkToBool(zoom.colorSpaceXform())) {
236 fColorSpaceHelper.setData(pdman, zoom.colorSpaceXform());
237 }
238 }
239
240 /////////////////////////////////////////////////////////////////////
241
onGetGLSLProcessorKey(const GrShaderCaps & caps,GrProcessorKeyBuilder * b) const242 void GrMagnifierEffect::onGetGLSLProcessorKey(const GrShaderCaps& caps,
243 GrProcessorKeyBuilder* b) const {
244 GrGLMagnifierEffect::GenKey(*this, caps, b);
245 }
246
onCreateGLSLInstance() const247 GrGLSLFragmentProcessor* GrMagnifierEffect::onCreateGLSLInstance() const {
248 return new GrGLMagnifierEffect;
249 }
250
251 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrMagnifierEffect);
252
253 #if GR_TEST_UTILS
TestCreate(GrProcessorTestData * d)254 sk_sp<GrFragmentProcessor> GrMagnifierEffect::TestCreate(GrProcessorTestData* d) {
255 sk_sp<GrTextureProxy> proxy = d->textureProxy(0);
256 const int kMaxWidth = 200;
257 const int kMaxHeight = 200;
258 const SkScalar kMaxInset = 20.0f;
259 uint32_t width = d->fRandom->nextULessThan(kMaxWidth);
260 uint32_t height = d->fRandom->nextULessThan(kMaxHeight);
261 SkScalar inset = d->fRandom->nextRangeScalar(1.0f, kMaxInset);
262 sk_sp<GrColorSpaceXform> colorSpaceXform = GrTest::TestColorXform(d->fRandom);
263
264 SkIRect bounds = SkIRect::MakeWH(SkIntToScalar(kMaxWidth), SkIntToScalar(kMaxHeight));
265 SkRect srcRect = SkRect::MakeWH(SkIntToScalar(width), SkIntToScalar(height));
266
267 sk_sp<GrFragmentProcessor> effect(GrMagnifierEffect::Make(
268 std::move(proxy),
269 std::move(colorSpaceXform),
270 bounds,
271 srcRect,
272 srcRect.width() / bounds.width(),
273 srcRect.height() / bounds.height(),
274 bounds.width() / inset,
275 bounds.height() / inset));
276 SkASSERT(effect);
277 return effect;
278 }
279 #endif
280
281 ///////////////////////////////////////////////////////////////////////////////
282
onIsEqual(const GrFragmentProcessor & sBase) const283 bool GrMagnifierEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
284 const GrMagnifierEffect& s = sBase.cast<GrMagnifierEffect>();
285 return (this->fBounds == s.fBounds &&
286 this->fSrcRect == s.fSrcRect &&
287 this->fXInvZoom == s.fXInvZoom &&
288 this->fYInvZoom == s.fYInvZoom &&
289 this->fXInvInset == s.fXInvInset &&
290 this->fYInvInset == s.fYInvInset);
291 }
292
293 #endif
294
295 ////////////////////////////////////////////////////////////////////////////////
296
SkMagnifierImageFilter(const SkRect & srcRect,SkScalar inset,sk_sp<SkImageFilter> input,const CropRect * cropRect)297 SkMagnifierImageFilter::SkMagnifierImageFilter(const SkRect& srcRect,
298 SkScalar inset,
299 sk_sp<SkImageFilter> input,
300 const CropRect* cropRect)
301 : INHERITED(&input, 1, cropRect)
302 , fSrcRect(srcRect)
303 , fInset(inset) {
304 SkASSERT(srcRect.left() >= 0 && srcRect.top() >= 0 && inset >= 0);
305 }
306
CreateProc(SkReadBuffer & buffer)307 sk_sp<SkFlattenable> SkMagnifierImageFilter::CreateProc(SkReadBuffer& buffer) {
308 SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
309 SkRect src;
310 buffer.readRect(&src);
311 return Make(src, buffer.readScalar(), common.getInput(0), &common.cropRect());
312 }
313
flatten(SkWriteBuffer & buffer) const314 void SkMagnifierImageFilter::flatten(SkWriteBuffer& buffer) const {
315 this->INHERITED::flatten(buffer);
316 buffer.writeRect(fSrcRect);
317 buffer.writeScalar(fInset);
318 }
319
onFilterImage(SkSpecialImage * source,const Context & ctx,SkIPoint * offset) const320 sk_sp<SkSpecialImage> SkMagnifierImageFilter::onFilterImage(SkSpecialImage* source,
321 const Context& ctx,
322 SkIPoint* offset) const {
323 SkIPoint inputOffset = SkIPoint::Make(0, 0);
324 sk_sp<SkSpecialImage> input(this->filterInput(0, source, ctx, &inputOffset));
325 if (!input) {
326 return nullptr;
327 }
328
329 const SkIRect inputBounds = SkIRect::MakeXYWH(inputOffset.x(), inputOffset.y(),
330 input->width(), input->height());
331
332 SkIRect bounds;
333 if (!this->applyCropRect(ctx, inputBounds, &bounds)) {
334 return nullptr;
335 }
336
337 SkScalar invInset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1;
338
339 SkScalar invXZoom = fSrcRect.width() / bounds.width();
340 SkScalar invYZoom = fSrcRect.height() / bounds.height();
341
342
343 #if SK_SUPPORT_GPU
344 if (source->isTextureBacked()) {
345 GrContext* context = source->getContext();
346
347 sk_sp<GrTextureProxy> inputProxy(input->asTextureProxyRef(context));
348 SkASSERT(inputProxy);
349
350 offset->fX = bounds.left();
351 offset->fY = bounds.top();
352 bounds.offset(-inputOffset);
353
354 SkColorSpace* dstColorSpace = ctx.outputProperties().colorSpace();
355 sk_sp<GrColorSpaceXform> colorSpaceXform = GrColorSpaceXform::Make(input->getColorSpace(),
356 dstColorSpace);
357 sk_sp<GrFragmentProcessor> fp(GrMagnifierEffect::Make(
358 std::move(inputProxy),
359 std::move(colorSpaceXform),
360 bounds,
361 fSrcRect,
362 invXZoom,
363 invYZoom,
364 bounds.width() * invInset,
365 bounds.height() * invInset));
366 if (!fp) {
367 return nullptr;
368 }
369
370 return DrawWithFP(context, std::move(fp), bounds, ctx.outputProperties());
371 }
372 #endif
373
374 SkBitmap inputBM;
375
376 if (!input->getROPixels(&inputBM)) {
377 return nullptr;
378 }
379
380 if ((inputBM.colorType() != kN32_SkColorType) ||
381 (fSrcRect.width() >= inputBM.width()) || (fSrcRect.height() >= inputBM.height())) {
382 return nullptr;
383 }
384
385 SkASSERT(inputBM.getPixels());
386 if (!inputBM.getPixels() || inputBM.width() <= 0 || inputBM.height() <= 0) {
387 return nullptr;
388 }
389
390 const SkImageInfo info = SkImageInfo::MakeN32Premul(bounds.width(), bounds.height());
391
392 SkBitmap dst;
393 if (!dst.tryAllocPixels(info)) {
394 return nullptr;
395 }
396
397 SkColor* dptr = dst.getAddr32(0, 0);
398 int dstWidth = dst.width(), dstHeight = dst.height();
399 for (int y = 0; y < dstHeight; ++y) {
400 for (int x = 0; x < dstWidth; ++x) {
401 SkScalar x_dist = SkMin32(x, dstWidth - x - 1) * invInset;
402 SkScalar y_dist = SkMin32(y, dstHeight - y - 1) * invInset;
403 SkScalar weight = 0;
404
405 static const SkScalar kScalar2 = SkScalar(2);
406
407 // To create a smooth curve at the corners, we need to work on
408 // a square twice the size of the inset.
409 if (x_dist < kScalar2 && y_dist < kScalar2) {
410 x_dist = kScalar2 - x_dist;
411 y_dist = kScalar2 - y_dist;
412
413 SkScalar dist = SkScalarSqrt(SkScalarSquare(x_dist) +
414 SkScalarSquare(y_dist));
415 dist = SkMaxScalar(kScalar2 - dist, 0);
416 weight = SkMinScalar(SkScalarSquare(dist), SK_Scalar1);
417 } else {
418 SkScalar sqDist = SkMinScalar(SkScalarSquare(x_dist),
419 SkScalarSquare(y_dist));
420 weight = SkMinScalar(sqDist, SK_Scalar1);
421 }
422
423 SkScalar x_interp = weight * (fSrcRect.x() + x * invXZoom) + (1 - weight) * x;
424 SkScalar y_interp = weight * (fSrcRect.y() + y * invYZoom) + (1 - weight) * y;
425
426 int x_val = SkTPin(bounds.x() + SkScalarFloorToInt(x_interp), 0, inputBM.width() - 1);
427 int y_val = SkTPin(bounds.y() + SkScalarFloorToInt(y_interp), 0, inputBM.height() - 1);
428
429 *dptr = *inputBM.getAddr32(x_val, y_val);
430 dptr++;
431 }
432 }
433
434 offset->fX = bounds.left();
435 offset->fY = bounds.top();
436 return SkSpecialImage::MakeFromRaster(SkIRect::MakeWH(bounds.width(), bounds.height()),
437 dst);
438 }
439
onMakeColorSpace(SkColorSpaceXformer * xformer) const440 sk_sp<SkImageFilter> SkMagnifierImageFilter::onMakeColorSpace(SkColorSpaceXformer* xformer) const {
441 SkASSERT(1 == this->countInputs());
442 auto input = xformer->apply(this->getInput(0));
443 if (input.get() != this->getInput(0)) {
444 return SkMagnifierImageFilter::Make(fSrcRect, fInset, std::move(input),
445 this->getCropRectIfSet());
446 }
447 return this->refMe();
448 }
449
450 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const451 void SkMagnifierImageFilter::toString(SkString* str) const {
452 str->appendf("SkMagnifierImageFilter: (");
453 str->appendf("src: (%f,%f,%f,%f) ",
454 fSrcRect.fLeft, fSrcRect.fTop, fSrcRect.fRight, fSrcRect.fBottom);
455 str->appendf("inset: %f", fInset);
456 str->append(")");
457 }
458 #endif
459