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#include "SkImageFilterCacheKey.h"
10
11#include "SkBitmap.h"
12#include "SkBitmapDevice.h"
13#include "SkChecksum.h"
14#include "SkDevice.h"
15#include "SkLocalMatrixImageFilter.h"
16#include "SkMatrixImageFilter.h"
17#include "SkOncePtr.h"
18#include "SkReadBuffer.h"
19#include "SkRect.h"
20#include "SkSpecialImage.h"
21#include "SkTDynamicHash.h"
22#include "SkTInternalLList.h"
23#include "SkValidationUtils.h"
24#include "SkWriteBuffer.h"
25#if SK_SUPPORT_GPU
26#include "GrContext.h"
27#include "GrDrawContext.h"
28#include "SkGrPixelRef.h"
29#include "SkGr.h"
30#endif
31
32#ifdef SK_BUILD_FOR_IOS
33  enum { kDefaultCacheSize = 2 * 1024 * 1024 };
34#else
35  enum { kDefaultCacheSize = 128 * 1024 * 1024 };
36#endif
37
38#ifndef SK_IGNORE_TO_STRING
39void SkImageFilter::CropRect::toString(SkString* str) const {
40    if (!fFlags) {
41        return;
42    }
43
44    str->appendf("cropRect (");
45    if (fFlags & CropRect::kHasLeft_CropEdge) {
46        str->appendf("%.2f, ", fRect.fLeft);
47    } else {
48        str->appendf("X, ");
49    }
50    if (fFlags & CropRect::kHasTop_CropEdge) {
51        str->appendf("%.2f, ", fRect.fTop);
52    } else {
53        str->appendf("X, ");
54    }
55    if (fFlags & CropRect::kHasWidth_CropEdge) {
56        str->appendf("%.2f, ", fRect.width());
57    } else {
58        str->appendf("X, ");
59    }
60    if (fFlags & CropRect::kHasHeight_CropEdge) {
61        str->appendf("%.2f", fRect.height());
62    } else {
63        str->appendf("X");
64    }
65    str->appendf(") ");
66}
67#endif
68
69void SkImageFilter::CropRect::applyTo(const SkIRect& imageBounds,
70                                      const SkMatrix& ctm,
71                                      SkIRect* cropped) const {
72    *cropped = imageBounds;
73    if (fFlags) {
74        SkRect devCropR;
75        ctm.mapRect(&devCropR, fRect);
76        const SkIRect devICropR = devCropR.roundOut();
77
78        // Compute the left/top first, in case we have to read them to compute right/bottom
79        if (fFlags & kHasLeft_CropEdge) {
80            cropped->fLeft = devICropR.fLeft;
81        }
82        if (fFlags & kHasTop_CropEdge) {
83            cropped->fTop = devICropR.fTop;
84        }
85        if (fFlags & kHasWidth_CropEdge) {
86            cropped->fRight = cropped->fLeft + devICropR.width();
87        }
88        if (fFlags & kHasHeight_CropEdge) {
89            cropped->fBottom = cropped->fTop + devICropR.height();
90        }
91    }
92}
93
94///////////////////////////////////////////////////////////////////////////////////////////////////
95
96static int32_t next_image_filter_unique_id() {
97    static int32_t gImageFilterUniqueID;
98
99    // Never return 0.
100    int32_t id;
101    do {
102        id = sk_atomic_inc(&gImageFilterUniqueID) + 1;
103    } while (0 == id);
104    return id;
105}
106
107SkImageFilter::Common::~Common() {
108    for (int i = 0; i < fInputs.count(); ++i) {
109        SkSafeUnref(fInputs[i]);
110    }
111}
112
113void SkImageFilter::Common::allocInputs(int count) {
114    const size_t size = count * sizeof(SkImageFilter*);
115    fInputs.reset(count);
116    sk_bzero(fInputs.get(), size);
117}
118
119void SkImageFilter::Common::detachInputs(SkImageFilter** inputs) {
120    const size_t size = fInputs.count() * sizeof(SkImageFilter*);
121    memcpy(inputs, fInputs.get(), size);
122    sk_bzero(fInputs.get(), size);
123}
124
125bool SkImageFilter::Common::unflatten(SkReadBuffer& buffer, int expectedCount) {
126    const int count = buffer.readInt();
127    if (!buffer.validate(count >= 0)) {
128        return false;
129    }
130    if (!buffer.validate(expectedCount < 0 || count == expectedCount)) {
131        return false;
132    }
133
134    this->allocInputs(count);
135    for (int i = 0; i < count; i++) {
136        if (buffer.readBool()) {
137            fInputs[i] = buffer.readImageFilter();
138        }
139        if (!buffer.isValid()) {
140            return false;
141        }
142    }
143    SkRect rect;
144    buffer.readRect(&rect);
145    if (!buffer.isValid() || !buffer.validate(SkIsValidRect(rect))) {
146        return false;
147    }
148
149    uint32_t flags = buffer.readUInt();
150    fCropRect = CropRect(rect, flags);
151    if (buffer.isVersionLT(SkReadBuffer::kImageFilterNoUniqueID_Version)) {
152
153        (void) buffer.readUInt();
154    }
155    return buffer.isValid();
156}
157
158///////////////////////////////////////////////////////////////////////////////////////////////////
159
160SkImageFilter::SkImageFilter(int inputCount, SkImageFilter** inputs, const CropRect* cropRect)
161  : fInputCount(inputCount),
162    fInputs(new SkImageFilter*[inputCount]),
163    fUsesSrcInput(false),
164    fCropRect(cropRect ? *cropRect : CropRect(SkRect(), 0x0)),
165    fUniqueID(next_image_filter_unique_id()) {
166    for (int i = 0; i < inputCount; ++i) {
167        if (nullptr == inputs[i] || inputs[i]->usesSrcInput()) {
168            fUsesSrcInput = true;
169        }
170        fInputs[i] = inputs[i];
171        SkSafeRef(fInputs[i]);
172    }
173}
174
175SkImageFilter::~SkImageFilter() {
176    for (int i = 0; i < fInputCount; i++) {
177        SkSafeUnref(fInputs[i]);
178    }
179    delete[] fInputs;
180    Cache::Get()->purgeByKeys(fCacheKeys.begin(), fCacheKeys.count());
181}
182
183SkImageFilter::SkImageFilter(int inputCount, SkReadBuffer& buffer)
184  : fUsesSrcInput(false)
185  , fUniqueID(next_image_filter_unique_id()) {
186    Common common;
187    if (common.unflatten(buffer, inputCount)) {
188        fCropRect = common.cropRect();
189        fInputCount = common.inputCount();
190        fInputs = new SkImageFilter* [fInputCount];
191        common.detachInputs(fInputs);
192        for (int i = 0; i < fInputCount; ++i) {
193            if (nullptr == fInputs[i] || fInputs[i]->usesSrcInput()) {
194                fUsesSrcInput = true;
195            }
196        }
197    } else {
198        fInputCount = 0;
199        fInputs = nullptr;
200    }
201}
202
203void SkImageFilter::flatten(SkWriteBuffer& buffer) const {
204    buffer.writeInt(fInputCount);
205    for (int i = 0; i < fInputCount; i++) {
206        SkImageFilter* input = this->getInput(i);
207        buffer.writeBool(input != nullptr);
208        if (input != nullptr) {
209            buffer.writeFlattenable(input);
210        }
211    }
212    buffer.writeRect(fCropRect.rect());
213    buffer.writeUInt(fCropRect.flags());
214}
215
216bool SkImageFilter::filterImageDeprecated(Proxy* proxy, const SkBitmap& src,
217                                          const Context& context,
218                                          SkBitmap* result, SkIPoint* offset) const {
219    SkASSERT(result);
220    SkASSERT(offset);
221    uint32_t srcGenID = fUsesSrcInput ? src.getGenerationID() : 0;
222    Cache::Key key(fUniqueID, context.ctm(), context.clipBounds(),
223                   srcGenID, SkIRect::MakeWH(0, 0));
224    if (context.cache()) {
225        if (context.cache()->get(key, result, offset)) {
226            return true;
227        }
228    }
229    /*
230     *  Give the proxy first shot at the filter. If it returns false, ask
231     *  the filter to do it.
232     */
233    if ((proxy && proxy->filterImage(this, src, context, result, offset)) ||
234        this->onFilterImageDeprecated(proxy, src, context, result, offset)) {
235        if (context.cache()) {
236            context.cache()->set(key, *result, *offset);
237            SkAutoMutexAcquire mutex(fMutex);
238            fCacheKeys.push_back(key);
239        }
240        return true;
241    }
242    return false;
243}
244
245bool SkImageFilter::filterInputDeprecated(int index, Proxy* proxy, const SkBitmap& src,
246                                          const Context& ctx,
247                                          SkBitmap* result, SkIPoint* offset) const {
248    SkImageFilter* input = this->getInput(index);
249    if (!input) {
250        return true;
251    }
252    return input->filterImageDeprecated(proxy, src, this->mapContext(ctx), result, offset);
253}
254
255bool SkImageFilter::filterBounds(const SkIRect& src, const SkMatrix& ctm, SkIRect* dst,
256                                 MapDirection direction) const {
257    SkASSERT(dst);
258    SkIRect bounds;
259    if (kReverse_MapDirection == direction) {
260        this->onFilterNodeBounds(src, ctm, &bounds, direction);
261        return this->onFilterBounds(bounds, ctm, dst, direction);
262    } else {
263        SkIRect temp;
264        if (!this->onFilterBounds(src, ctm, &bounds, direction)) {
265            return false;
266        }
267        this->onFilterNodeBounds(bounds, ctm, &temp, direction);
268        this->getCropRect().applyTo(temp, ctm, dst);
269        return true;
270    }
271}
272
273void SkImageFilter::computeFastBounds(const SkRect& src, SkRect* dst) const {
274    if (0 == fInputCount) {
275        *dst = src;
276        return;
277    }
278    if (this->getInput(0)) {
279        this->getInput(0)->computeFastBounds(src, dst);
280    } else {
281        *dst = src;
282    }
283    for (int i = 1; i < fInputCount; i++) {
284        SkImageFilter* input = this->getInput(i);
285        if (input) {
286            SkRect bounds;
287            input->computeFastBounds(src, &bounds);
288            dst->join(bounds);
289        } else {
290            dst->join(src);
291        }
292    }
293}
294
295bool SkImageFilter::canComputeFastBounds() const {
296    for (int i = 0; i < fInputCount; i++) {
297        SkImageFilter* input = this->getInput(i);
298        if (input && !input->canComputeFastBounds()) {
299            return false;
300        }
301    }
302    return true;
303}
304
305bool SkImageFilter::onFilterImageDeprecated(Proxy*, const SkBitmap&, const Context&,
306                                            SkBitmap*, SkIPoint*) const {
307    return false;
308}
309
310bool SkImageFilter::canFilterImageGPU() const {
311    return this->asFragmentProcessor(nullptr, nullptr, SkMatrix::I(), SkIRect());
312}
313
314bool SkImageFilter::filterImageGPUDeprecated(Proxy* proxy, const SkBitmap& src, const Context& ctx,
315                                             SkBitmap* result, SkIPoint* offset) const {
316#if SK_SUPPORT_GPU
317    SkBitmap input = src;
318    SkASSERT(fInputCount == 1);
319    SkIPoint srcOffset = SkIPoint::Make(0, 0);
320    if (!this->filterInputGPUDeprecated(0, proxy, src, ctx, &input, &srcOffset)) {
321        return false;
322    }
323    GrTexture* srcTexture = input.getTexture();
324    SkIRect bounds;
325    if (!this->applyCropRectDeprecated(ctx, proxy, input, &srcOffset, &bounds, &input)) {
326        return false;
327    }
328    GrContext* context = srcTexture->getContext();
329
330    GrSurfaceDesc desc;
331    desc.fFlags = kRenderTarget_GrSurfaceFlag,
332    desc.fWidth = bounds.width();
333    desc.fHeight = bounds.height();
334    desc.fConfig = kRGBA_8888_GrPixelConfig;
335
336    SkAutoTUnref<GrTexture> dst(context->textureProvider()->createApproxTexture(desc));
337    if (!dst) {
338        return false;
339    }
340
341    GrFragmentProcessor* fp;
342    offset->fX = bounds.left();
343    offset->fY = bounds.top();
344    bounds.offset(-srcOffset);
345    SkMatrix matrix(ctx.ctm());
346    matrix.postTranslate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top()));
347    GrPaint paint;
348    if (this->asFragmentProcessor(&fp, srcTexture, matrix, bounds)) {
349        SkASSERT(fp);
350        paint.addColorFragmentProcessor(fp)->unref();
351        paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
352
353        SkAutoTUnref<GrDrawContext> drawContext(context->drawContext(dst->asRenderTarget()));
354        if (drawContext) {
355            SkRect srcRect = SkRect::Make(bounds);
356            SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
357            GrClip clip(dstRect);
358            drawContext->fillRectToRect(clip, paint, SkMatrix::I(), dstRect, srcRect);
359
360            GrWrapTextureInBitmap(dst, bounds.width(), bounds.height(), false, result);
361            return true;
362        }
363    }
364#endif
365    return false;
366}
367
368bool SkImageFilter::asAColorFilter(SkColorFilter** filterPtr) const {
369    SkASSERT(nullptr != filterPtr);
370    if (!this->isColorFilterNode(filterPtr)) {
371        return false;
372    }
373    if (nullptr != this->getInput(0) || (*filterPtr)->affectsTransparentBlack()) {
374        (*filterPtr)->unref();
375        return false;
376    }
377    return true;
378}
379
380bool SkImageFilter::applyCropRect(const Context& ctx, const SkIRect& srcBounds,
381                                  SkIRect* dstBounds) const {
382    this->onFilterNodeBounds(srcBounds, ctx.ctm(), dstBounds, kForward_MapDirection);
383    fCropRect.applyTo(*dstBounds, ctx.ctm(), dstBounds);
384    // Intersect against the clip bounds, in case the crop rect has
385    // grown the bounds beyond the original clip. This can happen for
386    // example in tiling, where the clip is much smaller than the filtered
387    // primitive. If we didn't do this, we would be processing the filter
388    // at the full crop rect size in every tile.
389    return dstBounds->intersect(ctx.clipBounds());
390}
391
392bool SkImageFilter::applyCropRectDeprecated(const Context& ctx, Proxy* proxy, const SkBitmap& src,
393                                            SkIPoint* srcOffset, SkIRect* bounds,
394                                            SkBitmap* dst) const {
395    SkIRect srcBounds;
396    src.getBounds(&srcBounds);
397    srcBounds.offset(*srcOffset);
398    SkIRect dstBounds;
399    this->onFilterNodeBounds(srcBounds, ctx.ctm(), &dstBounds, kForward_MapDirection);
400    fCropRect.applyTo(dstBounds, ctx.ctm(), bounds);
401    if (!bounds->intersect(ctx.clipBounds())) {
402        return false;
403    }
404
405    if (srcBounds.contains(*bounds)) {
406        *dst = src;
407        return true;
408    } else {
409        SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(bounds->width(), bounds->height()));
410        if (!device) {
411            return false;
412        }
413        SkCanvas canvas(device);
414        canvas.clear(0x00000000);
415        canvas.drawBitmap(src, srcOffset->x() - bounds->x(), srcOffset->y() - bounds->y());
416        *srcOffset = SkIPoint::Make(bounds->x(), bounds->y());
417        *dst = device->accessBitmap(false);
418        return true;
419    }
420}
421
422bool SkImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
423                                   SkIRect* dst, MapDirection direction) const {
424    if (fInputCount < 1) {
425        *dst = src;
426        return true;
427    }
428
429    SkIRect totalBounds;
430    for (int i = 0; i < fInputCount; ++i) {
431        SkImageFilter* filter = this->getInput(i);
432        SkIRect rect = src;
433        if (filter && !filter->filterBounds(src, ctm, &rect, direction)) {
434            return false;
435        }
436        if (0 == i) {
437            totalBounds = rect;
438        } else {
439            totalBounds.join(rect);
440        }
441    }
442
443    // don't modify dst until now, so we don't accidentally change it in the
444    // loop, but then return false on the next filter.
445    *dst = totalBounds;
446    return true;
447}
448
449void SkImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix&,
450                                       SkIRect* dst, MapDirection) const {
451    *dst = src;
452}
453
454
455SkImageFilter::Context SkImageFilter::mapContext(const Context& ctx) const {
456    SkIRect clipBounds;
457    this->onFilterNodeBounds(ctx.clipBounds(), ctx.ctm(), &clipBounds,
458                             MapDirection::kReverse_MapDirection);
459    return Context(ctx.ctm(), clipBounds, ctx.cache());
460}
461
462bool SkImageFilter::asFragmentProcessor(GrFragmentProcessor**, GrTexture*,
463                                        const SkMatrix&, const SkIRect&) const {
464    return false;
465}
466
467SkImageFilter* SkImageFilter::CreateMatrixFilter(const SkMatrix& matrix,
468                                                 SkFilterQuality filterQuality,
469                                                 SkImageFilter* input) {
470    return SkMatrixImageFilter::Create(matrix, filterQuality, input);
471}
472
473SkImageFilter* SkImageFilter::newWithLocalMatrix(const SkMatrix& matrix) const {
474    // SkLocalMatrixImageFilter takes SkImage* in its factory, but logically that parameter
475    // is *always* treated as a const ptr. Hence the const-cast here.
476    //
477    return SkLocalMatrixImageFilter::Create(matrix, const_cast<SkImageFilter*>(this));
478}
479
480#if SK_SUPPORT_GPU
481
482bool SkImageFilter::filterInputGPUDeprecated(int index, SkImageFilter::Proxy* proxy,
483                                             const SkBitmap& src, const Context& ctx,
484                                             SkBitmap* result, SkIPoint* offset) const {
485    SkImageFilter* input = this->getInput(index);
486    if (!input) {
487        return true;
488    }
489    // Ensure that GrContext calls under filterImage and filterImageGPU below will see an identity
490    // matrix with no clip and that the matrix, clip, and render target set before this function was
491    // called are restored before we return to the caller.
492    GrContext* context = src.getTexture()->getContext();
493    if (input->filterImageDeprecated(proxy, src, this->mapContext(ctx), result, offset)) {
494        if (!result->getTexture()) {
495            const SkImageInfo info = result->info();
496            if (kUnknown_SkColorType == info.colorType()) {
497                return false;
498            }
499            SkAutoTUnref<GrTexture> resultTex(
500                GrRefCachedBitmapTexture(context, *result, GrTextureParams::ClampNoFilter()));
501            if (!resultTex) {
502                return false;
503            }
504            result->setPixelRef(new SkGrPixelRef(info, resultTex))->unref();
505        }
506        return true;
507    } else {
508        return false;
509    }
510}
511#endif
512
513namespace {
514
515class CacheImpl : public SkImageFilter::Cache {
516public:
517    CacheImpl(size_t maxBytes) : fMaxBytes(maxBytes), fCurrentBytes(0) { }
518    ~CacheImpl() override {
519        SkTDynamicHash<Value, Key>::Iter iter(&fLookup);
520
521        while (!iter.done()) {
522            Value* v = &*iter;
523            ++iter;
524            delete v;
525        }
526    }
527    struct Value {
528        Value(const Key& key, const SkBitmap& bitmap, const SkIPoint& offset)
529            : fKey(key), fBitmap(bitmap), fOffset(offset) {}
530        Value(const Key& key, SkSpecialImage* image, const SkIPoint& offset)
531            : fKey(key), fImage(SkRef(image)), fOffset(offset) {}
532
533        Key fKey;
534        SkBitmap fBitmap;
535        SkAutoTUnref<SkSpecialImage> fImage;
536        SkIPoint fOffset;
537        static const Key& GetKey(const Value& v) {
538            return v.fKey;
539        }
540        static uint32_t Hash(const Key& key) {
541            return SkChecksum::Murmur3(reinterpret_cast<const uint32_t*>(&key), sizeof(Key));
542        }
543        SK_DECLARE_INTERNAL_LLIST_INTERFACE(Value);
544    };
545
546    bool get(const Key& key, SkBitmap* result, SkIPoint* offset) const override {
547        SkAutoMutexAcquire mutex(fMutex);
548        if (Value* v = fLookup.find(key)) {
549            *result = v->fBitmap;
550            *offset = v->fOffset;
551            if (v != fLRU.head()) {
552                fLRU.remove(v);
553                fLRU.addToHead(v);
554            }
555            return true;
556        }
557        return false;
558    }
559
560    SkSpecialImage* get(const Key& key, SkIPoint* offset) const override {
561        SkAutoMutexAcquire mutex(fMutex);
562        if (Value* v = fLookup.find(key)) {
563            *offset = v->fOffset;
564            if (v != fLRU.head()) {
565                fLRU.remove(v);
566                fLRU.addToHead(v);
567            }
568            return v->fImage;
569        }
570        return nullptr;
571    }
572
573    void set(const Key& key, const SkBitmap& result, const SkIPoint& offset) override {
574        SkAutoMutexAcquire mutex(fMutex);
575        if (Value* v = fLookup.find(key)) {
576            this->removeInternal(v);
577        }
578        Value* v = new Value(key, result, offset);
579        fLookup.add(v);
580        fLRU.addToHead(v);
581        fCurrentBytes += result.getSize();
582        while (fCurrentBytes > fMaxBytes) {
583            Value* tail = fLRU.tail();
584            SkASSERT(tail);
585            if (tail == v) {
586                break;
587            }
588            this->removeInternal(tail);
589        }
590    }
591
592    void set(const Key& key, SkSpecialImage* image, const SkIPoint& offset) override {
593        SkAutoMutexAcquire mutex(fMutex);
594        if (Value* v = fLookup.find(key)) {
595            this->removeInternal(v);
596        }
597        Value* v = new Value(key, image, offset);
598        fLookup.add(v);
599        fLRU.addToHead(v);
600        fCurrentBytes += image->getSize();
601        while (fCurrentBytes > fMaxBytes) {
602            Value* tail = fLRU.tail();
603            SkASSERT(tail);
604            if (tail == v) {
605                break;
606            }
607            this->removeInternal(tail);
608        }
609    }
610
611    void purge() override {
612        SkAutoMutexAcquire mutex(fMutex);
613        while (fCurrentBytes > 0) {
614            Value* tail = fLRU.tail();
615            SkASSERT(tail);
616            this->removeInternal(tail);
617        }
618    }
619
620    void purgeByKeys(const Key keys[], int count) override {
621        SkAutoMutexAcquire mutex(fMutex);
622        for (int i = 0; i < count; i++) {
623            if (Value* v = fLookup.find(keys[i])) {
624                this->removeInternal(v);
625            }
626        }
627    }
628
629private:
630    void removeInternal(Value* v) {
631        if (v->fImage) {
632            fCurrentBytes -= v->fImage->getSize();
633        } else {
634            fCurrentBytes -= v->fBitmap.getSize();
635        }
636        fLRU.remove(v);
637        fLookup.remove(v->fKey);
638        delete v;
639    }
640private:
641    SkTDynamicHash<Value, Key>            fLookup;
642    mutable SkTInternalLList<Value>       fLRU;
643    size_t                                fMaxBytes;
644    size_t                                fCurrentBytes;
645    mutable SkMutex                       fMutex;
646};
647
648} // namespace
649
650SkImageFilter::Cache* SkImageFilter::Cache::Create(size_t maxBytes) {
651    return new CacheImpl(maxBytes);
652}
653
654SK_DECLARE_STATIC_ONCE_PTR(SkImageFilter::Cache, cache);
655SkImageFilter::Cache* SkImageFilter::Cache::Get() {
656    return cache.get([]{ return SkImageFilter::Cache::Create(kDefaultCacheSize); });
657}
658
659void SkImageFilter::PurgeCache() {
660    Cache::Get()->purge();
661}
662
663///////////////////////////////////////////////////////////////////////////////////////////////////
664
665SkBaseDevice* SkImageFilter::DeviceProxy::createDevice(int w, int h, TileUsage usage) {
666    SkBaseDevice::CreateInfo cinfo(SkImageInfo::MakeN32Premul(w, h),
667                                   kPossible_TileUsage == usage ? SkBaseDevice::kPossible_TileUsage
668                                                                : SkBaseDevice::kNever_TileUsage,
669                                   kUnknown_SkPixelGeometry,
670                                   false,   /* preserveLCDText */
671                                   true /*forImageFilter*/);
672    SkBaseDevice* dev = fDevice->onCreateDevice(cinfo, nullptr);
673    if (nullptr == dev) {
674        const SkSurfaceProps surfaceProps(fDevice->fSurfaceProps.flags(),
675                                          kUnknown_SkPixelGeometry);
676        dev = SkBitmapDevice::Create(cinfo.fInfo, surfaceProps);
677    }
678    return dev;
679}
680
681bool SkImageFilter::DeviceProxy::filterImage(const SkImageFilter* filter, const SkBitmap& src,
682                                       const SkImageFilter::Context& ctx,
683                                       SkBitmap* result, SkIPoint* offset) {
684    return fDevice->filterImage(filter, src, ctx, result, offset);
685}
686
687