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 "SkImageFilter.h"
9 
10 #include "SkCanvas.h"
11 #include "SkColorSpace_Base.h"
12 #include "SkFuzzLogging.h"
13 #include "SkImageFilterCache.h"
14 #include "SkLocalMatrixImageFilter.h"
15 #include "SkMatrixImageFilter.h"
16 #include "SkReadBuffer.h"
17 #include "SkRect.h"
18 #include "SkSpecialImage.h"
19 #include "SkSpecialSurface.h"
20 #include "SkValidationUtils.h"
21 #include "SkWriteBuffer.h"
22 #if SK_SUPPORT_GPU
23 #include "GrContext.h"
24 #include "GrFixedClip.h"
25 #include "GrRenderTargetContext.h"
26 #include "GrTextureProxy.h"
27 #include "SkGr.h"
28 #endif
29 
30 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const31 void SkImageFilter::CropRect::toString(SkString* str) const {
32     if (!fFlags) {
33         return;
34     }
35 
36     str->appendf("cropRect (");
37     if (fFlags & CropRect::kHasLeft_CropEdge) {
38         str->appendf("%.2f, ", fRect.fLeft);
39     } else {
40         str->appendf("X, ");
41     }
42     if (fFlags & CropRect::kHasTop_CropEdge) {
43         str->appendf("%.2f, ", fRect.fTop);
44     } else {
45         str->appendf("X, ");
46     }
47     if (fFlags & CropRect::kHasWidth_CropEdge) {
48         str->appendf("%.2f, ", fRect.width());
49     } else {
50         str->appendf("X, ");
51     }
52     if (fFlags & CropRect::kHasHeight_CropEdge) {
53         str->appendf("%.2f", fRect.height());
54     } else {
55         str->appendf("X");
56     }
57     str->appendf(") ");
58 }
59 #endif
60 
applyTo(const SkIRect & imageBounds,const SkMatrix & ctm,bool embiggen,SkIRect * cropped) const61 void SkImageFilter::CropRect::applyTo(const SkIRect& imageBounds,
62                                       const SkMatrix& ctm,
63                                       bool embiggen,
64                                       SkIRect* cropped) const {
65     *cropped = imageBounds;
66     if (fFlags) {
67         SkRect devCropR;
68         ctm.mapRect(&devCropR, fRect);
69         SkIRect devICropR = devCropR.roundOut();
70 
71         // Compute the left/top first, in case we need to modify the right/bottom for a missing edge
72         if (fFlags & kHasLeft_CropEdge) {
73             if (embiggen || devICropR.fLeft > cropped->fLeft) {
74                 cropped->fLeft = devICropR.fLeft;
75             }
76         } else {
77             devICropR.fRight = cropped->fLeft + devICropR.width();
78         }
79         if (fFlags & kHasTop_CropEdge) {
80             if (embiggen || devICropR.fTop > cropped->fTop) {
81                 cropped->fTop = devICropR.fTop;
82             }
83         } else {
84             devICropR.fBottom = cropped->fTop + devICropR.height();
85         }
86         if (fFlags & kHasWidth_CropEdge) {
87             if (embiggen || devICropR.fRight < cropped->fRight) {
88                 cropped->fRight = devICropR.fRight;
89             }
90         }
91         if (fFlags & kHasHeight_CropEdge) {
92             if (embiggen || devICropR.fBottom < cropped->fBottom) {
93                 cropped->fBottom = devICropR.fBottom;
94             }
95         }
96     }
97 }
98 
99 ///////////////////////////////////////////////////////////////////////////////////////////////////
100 
next_image_filter_unique_id()101 static int32_t next_image_filter_unique_id() {
102     static int32_t gImageFilterUniqueID;
103 
104     // Never return 0.
105     int32_t id;
106     do {
107         id = sk_atomic_inc(&gImageFilterUniqueID) + 1;
108     } while (0 == id);
109     return id;
110 }
111 
allocInputs(int count)112 void SkImageFilter::Common::allocInputs(int count) {
113     fInputs.reset(count);
114 }
115 
unflatten(SkReadBuffer & buffer,int expectedCount)116 bool SkImageFilter::Common::unflatten(SkReadBuffer& buffer, int expectedCount) {
117     const int count = buffer.readInt();
118     if (!buffer.validate(count >= 0)) {
119         return false;
120     }
121     if (!buffer.validate(expectedCount < 0 || count == expectedCount)) {
122         return false;
123     }
124 
125     SkFUZZF(("allocInputs: %d\n", count));
126     this->allocInputs(count);
127     for (int i = 0; i < count; i++) {
128         if (buffer.readBool()) {
129             fInputs[i] = sk_sp<SkImageFilter>(buffer.readImageFilter());
130         }
131         if (!buffer.isValid()) {
132             return false;
133         }
134     }
135     SkRect rect;
136     buffer.readRect(&rect);
137     if (!buffer.isValid() || !buffer.validate(SkIsValidRect(rect))) {
138         return false;
139     }
140 
141     uint32_t flags = buffer.readUInt();
142     fCropRect = CropRect(rect, flags);
143     if (buffer.isVersionLT(SkReadBuffer::kImageFilterNoUniqueID_Version)) {
144 
145         (void) buffer.readUInt();
146     }
147     return buffer.isValid();
148 }
149 
150 ///////////////////////////////////////////////////////////////////////////////////////////////////
151 
init(sk_sp<SkImageFilter> * inputs,int inputCount,const CropRect * cropRect)152 void SkImageFilter::init(sk_sp<SkImageFilter>* inputs,
153                          int inputCount,
154                          const CropRect* cropRect) {
155     fCropRect = cropRect ? *cropRect : CropRect(SkRect(), 0x0);
156 
157     fInputs.reset(inputCount);
158 
159     for (int i = 0; i < inputCount; ++i) {
160         if (!inputs[i] || inputs[i]->usesSrcInput()) {
161             fUsesSrcInput = true;
162         }
163         fInputs[i] = inputs[i];
164     }
165 }
166 
SkImageFilter(sk_sp<SkImageFilter> * inputs,int inputCount,const CropRect * cropRect)167 SkImageFilter::SkImageFilter(sk_sp<SkImageFilter>* inputs,
168                              int inputCount,
169                              const CropRect* cropRect)
170     : fUsesSrcInput(false)
171     , fUniqueID(next_image_filter_unique_id()) {
172     this->init(inputs, inputCount, cropRect);
173 }
174 
~SkImageFilter()175 SkImageFilter::~SkImageFilter() {
176     SkImageFilterCache::Get()->purgeByKeys(fCacheKeys.begin(), fCacheKeys.count());
177 }
178 
SkImageFilter(int inputCount,SkReadBuffer & buffer)179 SkImageFilter::SkImageFilter(int inputCount, SkReadBuffer& buffer)
180     : fUsesSrcInput(false)
181     , fCropRect(SkRect(), 0x0)
182     , fUniqueID(next_image_filter_unique_id()) {
183     Common common;
184     if (common.unflatten(buffer, inputCount)) {
185         this->init(common.inputs(), common.inputCount(), &common.cropRect());
186     }
187 }
188 
flatten(SkWriteBuffer & buffer) const189 void SkImageFilter::flatten(SkWriteBuffer& buffer) const {
190     buffer.writeInt(fInputs.count());
191     for (int i = 0; i < fInputs.count(); i++) {
192         SkImageFilter* input = this->getInput(i);
193         buffer.writeBool(input != nullptr);
194         if (input != nullptr) {
195             buffer.writeFlattenable(input);
196         }
197     }
198     buffer.writeRect(fCropRect.rect());
199     buffer.writeUInt(fCropRect.flags());
200 }
201 
filterImage(SkSpecialImage * src,const Context & context,SkIPoint * offset) const202 sk_sp<SkSpecialImage> SkImageFilter::filterImage(SkSpecialImage* src, const Context& context,
203                                                  SkIPoint* offset) const {
204     SkASSERT(src && offset);
205 
206     uint32_t srcGenID = fUsesSrcInput ? src->uniqueID() : 0;
207     const SkIRect srcSubset = fUsesSrcInput ? src->subset() : SkIRect::MakeWH(0, 0);
208     SkImageFilterCacheKey key(fUniqueID, context.ctm(), context.clipBounds(), srcGenID, srcSubset);
209     if (context.cache()) {
210         sk_sp<SkSpecialImage> result = context.cache()->get(key, offset);
211         if (result) {
212             return result;
213         }
214     }
215 
216     sk_sp<SkSpecialImage> result(this->onFilterImage(src, context, offset));
217 
218 #if SK_SUPPORT_GPU
219     if (src->isTextureBacked() && result && !result->isTextureBacked()) {
220         // Keep the result on the GPU - this is still required for some
221         // image filters that don't support GPU in all cases
222         GrContext* context = src->getContext();
223         result = result->makeTextureImage(context);
224     }
225 #endif
226 
227     if (result && context.cache()) {
228         context.cache()->set(key, result.get(), *offset);
229         SkAutoMutexAcquire mutex(fMutex);
230         fCacheKeys.push_back(key);
231     }
232 
233     return result;
234 }
235 
filterBounds(const SkIRect & src,const SkMatrix & ctm,MapDirection direction) const236 SkIRect SkImageFilter::filterBounds(const SkIRect& src, const SkMatrix& ctm,
237                                  MapDirection direction) const {
238     if (kReverse_MapDirection == direction) {
239         SkIRect bounds = this->onFilterNodeBounds(src, ctm, direction);
240         return this->onFilterBounds(bounds, ctm, direction);
241     } else {
242         SkIRect bounds = this->onFilterBounds(src, ctm, direction);
243         bounds = this->onFilterNodeBounds(bounds, ctm, direction);
244         SkIRect dst;
245         this->getCropRect().applyTo(bounds, ctm, this->affectsTransparentBlack(), &dst);
246         return dst;
247     }
248 }
249 
computeFastBounds(const SkRect & src) const250 SkRect SkImageFilter::computeFastBounds(const SkRect& src) const {
251     if (0 == this->countInputs()) {
252         return src;
253     }
254     SkRect combinedBounds = this->getInput(0) ? this->getInput(0)->computeFastBounds(src) : src;
255     for (int i = 1; i < this->countInputs(); i++) {
256         SkImageFilter* input = this->getInput(i);
257         if (input) {
258             combinedBounds.join(input->computeFastBounds(src));
259         } else {
260             combinedBounds.join(src);
261         }
262     }
263     return combinedBounds;
264 }
265 
canComputeFastBounds() const266 bool SkImageFilter::canComputeFastBounds() const {
267     if (this->affectsTransparentBlack()) {
268         return false;
269     }
270     for (int i = 0; i < this->countInputs(); i++) {
271         SkImageFilter* input = this->getInput(i);
272         if (input && !input->canComputeFastBounds()) {
273             return false;
274         }
275     }
276     return true;
277 }
278 
279 #if SK_SUPPORT_GPU
DrawWithFP(GrContext * context,sk_sp<GrFragmentProcessor> fp,const SkIRect & bounds,const OutputProperties & outputProperties)280 sk_sp<SkSpecialImage> SkImageFilter::DrawWithFP(GrContext* context,
281                                                 sk_sp<GrFragmentProcessor> fp,
282                                                 const SkIRect& bounds,
283                                                 const OutputProperties& outputProperties) {
284     GrPaint paint;
285     paint.addColorFragmentProcessor(std::move(fp));
286     paint.setPorterDuffXPFactory(SkBlendMode::kSrc);
287 
288     sk_sp<SkColorSpace> colorSpace = sk_ref_sp(outputProperties.colorSpace());
289     GrPixelConfig config = GrRenderableConfigForColorSpace(colorSpace.get());
290     sk_sp<GrRenderTargetContext> renderTargetContext(context->makeDeferredRenderTargetContext(
291         SkBackingFit::kApprox, bounds.width(), bounds.height(), config, std::move(colorSpace)));
292     if (!renderTargetContext) {
293         return nullptr;
294     }
295     paint.setGammaCorrect(renderTargetContext->isGammaCorrect());
296 
297     SkIRect dstIRect = SkIRect::MakeWH(bounds.width(), bounds.height());
298     SkRect srcRect = SkRect::Make(bounds);
299     SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
300     GrFixedClip clip(dstIRect);
301     renderTargetContext->fillRectToRect(clip, std::move(paint), GrAA::kNo, SkMatrix::I(), dstRect,
302                                         srcRect);
303 
304     return SkSpecialImage::MakeDeferredFromGpu(context, dstIRect,
305                                                kNeedNewImageUniqueID_SpecialImage,
306                                                renderTargetContext->asTextureProxyRef(),
307                                                renderTargetContext->refColorSpace());
308 }
309 #endif
310 
asAColorFilter(SkColorFilter ** filterPtr) const311 bool SkImageFilter::asAColorFilter(SkColorFilter** filterPtr) const {
312     SkASSERT(nullptr != filterPtr);
313     if (!this->isColorFilterNode(filterPtr)) {
314         return false;
315     }
316     if (nullptr != this->getInput(0) || (*filterPtr)->affectsTransparentBlack()) {
317         (*filterPtr)->unref();
318         return false;
319     }
320     return true;
321 }
322 
canHandleComplexCTM() const323 bool SkImageFilter::canHandleComplexCTM() const {
324     if (!this->onCanHandleComplexCTM()) {
325         return false;
326     }
327     const int count = this->countInputs();
328     for (int i = 0; i < count; ++i) {
329         SkImageFilter* input = this->getInput(i);
330         if (input && !input->canHandleComplexCTM()) {
331             return false;
332         }
333     }
334     return true;
335 }
336 
applyCropRect(const Context & ctx,const SkIRect & srcBounds,SkIRect * dstBounds) const337 bool SkImageFilter::applyCropRect(const Context& ctx, const SkIRect& srcBounds,
338                                   SkIRect* dstBounds) const {
339     SkIRect temp = this->onFilterNodeBounds(srcBounds, ctx.ctm(), kForward_MapDirection);
340     fCropRect.applyTo(temp, ctx.ctm(), this->affectsTransparentBlack(), dstBounds);
341     // Intersect against the clip bounds, in case the crop rect has
342     // grown the bounds beyond the original clip. This can happen for
343     // example in tiling, where the clip is much smaller than the filtered
344     // primitive. If we didn't do this, we would be processing the filter
345     // at the full crop rect size in every tile.
346     return dstBounds->intersect(ctx.clipBounds());
347 }
348 
349 #if SK_SUPPORT_GPU
ImageToColorSpace(SkSpecialImage * src,const OutputProperties & outProps)350 sk_sp<SkSpecialImage> SkImageFilter::ImageToColorSpace(SkSpecialImage* src,
351                                                        const OutputProperties& outProps) {
352     // There are several conditions that determine if we actually need to convert the source to the
353     // destination's color space. Rather than duplicate that logic here, just try to make an xform
354     // object. If that produces something, then both are tagged, and the source is in a different
355     // gamut than the dest. There is some overhead to making the xform, but those are cached, and
356     // if we get one back, that means we're about to use it during the conversion anyway.
357     sk_sp<GrColorSpaceXform> colorSpaceXform = GrColorSpaceXform::Make(src->getColorSpace(),
358                                                                        outProps.colorSpace());
359 
360     if (!colorSpaceXform) {
361         // No xform needed, just return the original image
362         return sk_ref_sp(src);
363     }
364 
365     sk_sp<SkSpecialSurface> surf(src->makeSurface(outProps,
366                                                   SkISize::Make(src->width(), src->height())));
367     if (!surf) {
368         return sk_ref_sp(src);
369     }
370 
371     SkCanvas* canvas = surf->getCanvas();
372     SkASSERT(canvas);
373     SkPaint p;
374     p.setBlendMode(SkBlendMode::kSrc);
375     src->draw(canvas, 0, 0, &p);
376     return surf->makeImageSnapshot();
377 }
378 #endif
379 
380 // Return a larger (newWidth x newHeight) copy of 'src' with black padding
381 // around it.
pad_image(SkSpecialImage * src,const SkImageFilter::OutputProperties & outProps,int newWidth,int newHeight,int offX,int offY)382 static sk_sp<SkSpecialImage> pad_image(SkSpecialImage* src,
383                                        const SkImageFilter::OutputProperties& outProps,
384                                        int newWidth, int newHeight, int offX, int offY) {
385     // We would like to operate in the source's color space (so that we return an "identical"
386     // image, other than the padding. To achieve that, we'd create new output properties:
387     //
388     // SkImageFilter::OutputProperties outProps(src->getColorSpace());
389     //
390     // That fails in at least two ways. For formats that are texturable but not renderable (like
391     // F16 on some ES implementations), we can't create a surface to do the work. For sRGB, images
392     // may be tagged with an sRGB color space (which leads to an sRGB config in makeSurface). But
393     // the actual config of that sRGB image on a device with no sRGB support is non-sRGB.
394     //
395     // Rather than try to special case these situations, we execute the image padding in the
396     // destination color space. This should not affect the output of the DAG in (almost) any case,
397     // because the result of this call is going to be used as an input, where it would have been
398     // switched to the destination space anyway. The one exception would be a filter that expected
399     // to consume unclamped F16 data, but the padded version of the image is pre-clamped to 8888.
400     // We can revisit this logic if that ever becomes an actual problem.
401     sk_sp<SkSpecialSurface> surf(src->makeSurface(outProps, SkISize::Make(newWidth, newHeight)));
402     if (!surf) {
403         return nullptr;
404     }
405 
406     SkCanvas* canvas = surf->getCanvas();
407     SkASSERT(canvas);
408 
409     canvas->clear(0x0);
410 
411     src->draw(canvas, offX, offY, nullptr);
412 
413     return surf->makeImageSnapshot();
414 }
415 
applyCropRect(const Context & ctx,SkSpecialImage * src,SkIPoint * srcOffset,SkIRect * bounds) const416 sk_sp<SkSpecialImage> SkImageFilter::applyCropRect(const Context& ctx,
417                                                    SkSpecialImage* src,
418                                                    SkIPoint* srcOffset,
419                                                    SkIRect* bounds) const {
420     const SkIRect srcBounds = SkIRect::MakeXYWH(srcOffset->x(), srcOffset->y(),
421                                                 src->width(), src->height());
422 
423     SkIRect dstBounds = this->onFilterNodeBounds(srcBounds, ctx.ctm(), kForward_MapDirection);
424     fCropRect.applyTo(dstBounds, ctx.ctm(), this->affectsTransparentBlack(), bounds);
425     if (!bounds->intersect(ctx.clipBounds())) {
426         return nullptr;
427     }
428 
429     if (srcBounds.contains(*bounds)) {
430         return sk_sp<SkSpecialImage>(SkRef(src));
431     } else {
432         sk_sp<SkSpecialImage> img(pad_image(src, ctx.outputProperties(),
433                                             bounds->width(), bounds->height(),
434                                             srcOffset->x() - bounds->x(),
435                                             srcOffset->y() - bounds->y()));
436         *srcOffset = SkIPoint::Make(bounds->x(), bounds->y());
437         return img;
438     }
439 }
440 
onFilterBounds(const SkIRect & src,const SkMatrix & ctm,MapDirection direction) const441 SkIRect SkImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
442                                       MapDirection direction) const {
443     if (this->countInputs() < 1) {
444         return src;
445     }
446 
447     SkIRect totalBounds;
448     for (int i = 0; i < this->countInputs(); ++i) {
449         SkImageFilter* filter = this->getInput(i);
450         SkIRect rect = filter ? filter->filterBounds(src, ctm, direction) : src;
451         if (0 == i) {
452             totalBounds = rect;
453         } else {
454             totalBounds.join(rect);
455         }
456     }
457 
458     return totalBounds;
459 }
460 
onFilterNodeBounds(const SkIRect & src,const SkMatrix &,MapDirection) const461 SkIRect SkImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix&, MapDirection) const {
462     return src;
463 }
464 
465 
mapContext(const Context & ctx) const466 SkImageFilter::Context SkImageFilter::mapContext(const Context& ctx) const {
467     SkIRect clipBounds = this->onFilterNodeBounds(ctx.clipBounds(), ctx.ctm(),
468                                                   MapDirection::kReverse_MapDirection);
469     return Context(ctx.ctm(), clipBounds, ctx.cache(), ctx.outputProperties());
470 }
471 
MakeMatrixFilter(const SkMatrix & matrix,SkFilterQuality filterQuality,sk_sp<SkImageFilter> input)472 sk_sp<SkImageFilter> SkImageFilter::MakeMatrixFilter(const SkMatrix& matrix,
473                                                      SkFilterQuality filterQuality,
474                                                      sk_sp<SkImageFilter> input) {
475     return SkMatrixImageFilter::Make(matrix, filterQuality, std::move(input));
476 }
477 
makeWithLocalMatrix(const SkMatrix & matrix) const478 sk_sp<SkImageFilter> SkImageFilter::makeWithLocalMatrix(const SkMatrix& matrix) const {
479     // SkLocalMatrixImageFilter takes SkImage* in its factory, but logically that parameter
480     // is *always* treated as a const ptr. Hence the const-cast here.
481     //
482     SkImageFilter* nonConstThis = const_cast<SkImageFilter*>(this);
483     return SkLocalMatrixImageFilter::Make(matrix, sk_ref_sp<SkImageFilter>(nonConstThis));
484 }
485 
filterInput(int index,SkSpecialImage * src,const Context & ctx,SkIPoint * offset) const486 sk_sp<SkSpecialImage> SkImageFilter::filterInput(int index,
487                                                  SkSpecialImage* src,
488                                                  const Context& ctx,
489                                                  SkIPoint* offset) const {
490     SkImageFilter* input = this->getInput(index);
491     if (!input) {
492         return sk_sp<SkSpecialImage>(SkRef(src));
493     }
494 
495     sk_sp<SkSpecialImage> result(input->filterImage(src, this->mapContext(ctx), offset));
496 
497     SkASSERT(!result || src->isTextureBacked() == result->isTextureBacked());
498 
499     return result;
500 }
501 
PurgeCache()502 void SkImageFilter::PurgeCache() {
503     SkImageFilterCache::Get()->purge();
504 }
505