1 /*
2  * Copyright 2014 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 "GrAtlas.h"
9 #include "GrGpu.h"
10 #include "GrLayerCache.h"
11 #include "GrSurfacePriv.h"
12 
13 #ifdef SK_DEBUG
validate(const GrTexture * backingTexture) const14 void GrCachedLayer::validate(const GrTexture* backingTexture) const {
15     SkASSERT(SK_InvalidGenID != fKey.pictureID());
16 
17     if (fTexture) {
18         // If the layer is in some texture then it must occupy some rectangle
19         SkASSERT(!fRect.isEmpty());
20         if (!this->isAtlased()) {
21             // If it isn't atlased then the rectangle should start at the origin
22             SkASSERT(0.0f == fRect.fLeft && 0.0f == fRect.fTop);
23         }
24     } else {
25         SkASSERT(fRect.isEmpty());
26         SkASSERT(NULL == fPlot);
27         SkASSERT(!fLocked);     // layers without a texture cannot be locked
28     }
29 
30     if (fPlot) {
31         // If a layer has a plot (i.e., is atlased) then it must point to
32         // the backing texture. Additionally, its rect should be non-empty.
33         SkASSERT(fTexture && backingTexture == fTexture);
34         SkASSERT(!fRect.isEmpty());
35     }
36 
37     if (fLocked) {
38         // If a layer is locked it must have a texture (though it need not be
39         // the atlas-backing texture) and occupy some space.
40         SkASSERT(fTexture);
41         SkASSERT(!fRect.isEmpty());
42     }
43 
44     // Unfortunately there is a brief time where a layer can be locked
45     // but not used, so we can only check the "used implies locked"
46     // invariant.
47     if (fUses > 0) {
48         SkASSERT(fLocked);
49     } else {
50         SkASSERT(0 == fUses);
51     }
52 }
53 
54 class GrAutoValidateLayer : ::SkNoncopyable {
55 public:
GrAutoValidateLayer(GrTexture * backingTexture,const GrCachedLayer * layer)56     GrAutoValidateLayer(GrTexture* backingTexture, const GrCachedLayer* layer)
57         : fBackingTexture(backingTexture)
58         , fLayer(layer) {
59         if (fLayer) {
60             fLayer->validate(backingTexture);
61         }
62     }
~GrAutoValidateLayer()63     ~GrAutoValidateLayer() {
64         if (fLayer) {
65             fLayer->validate(fBackingTexture);
66         }
67     }
setBackingTexture(GrTexture * backingTexture)68     void setBackingTexture(GrTexture* backingTexture) {
69         SkASSERT(NULL == fBackingTexture || fBackingTexture == backingTexture);
70         fBackingTexture = backingTexture;
71     }
72 
73 private:
74     const GrTexture* fBackingTexture;
75     const GrCachedLayer* fLayer;
76 };
77 #endif
78 
GrLayerCache(GrContext * context)79 GrLayerCache::GrLayerCache(GrContext* context)
80     : fContext(context) {
81     memset(fPlotLocks, 0, sizeof(fPlotLocks));
82 }
83 
~GrLayerCache()84 GrLayerCache::~GrLayerCache() {
85 
86     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::Iter iter(&fLayerHash);
87     for (; !iter.done(); ++iter) {
88         GrCachedLayer* layer = &(*iter);
89         SkASSERT(0 == layer->uses());
90         this->unlock(layer);
91         SkDELETE(layer);
92     }
93 
94     SkASSERT(0 == fPictureHash.count());
95 
96     // The atlas only lets go of its texture when the atlas is deleted.
97     fAtlas.free();
98 }
99 
initAtlas()100 void GrLayerCache::initAtlas() {
101     SkASSERT(NULL == fAtlas.get());
102     GR_STATIC_ASSERT(kNumPlotsX*kNumPlotsX == GrPictureInfo::kNumPlots);
103 
104     SkISize textureSize = SkISize::Make(kAtlasTextureWidth, kAtlasTextureHeight);
105     fAtlas.reset(SkNEW_ARGS(GrAtlas, (fContext->getGpu(), kSkia8888_GrPixelConfig,
106                                       kRenderTarget_GrSurfaceFlag,
107                                       textureSize, kNumPlotsX, kNumPlotsY, false)));
108 }
109 
freeAll()110 void GrLayerCache::freeAll() {
111 
112     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::Iter iter(&fLayerHash);
113     for (; !iter.done(); ++iter) {
114         GrCachedLayer* layer = &(*iter);
115         this->unlock(layer);
116         SkDELETE(layer);
117     }
118     fLayerHash.rewind();
119 
120     // The atlas only lets go of its texture when the atlas is deleted.
121     fAtlas.free();
122 }
123 
createLayer(uint32_t pictureID,int start,int stop,const SkIRect & srcIR,const SkIRect & dstIR,const SkMatrix & initialMat,const unsigned * key,int keySize,const SkPaint * paint)124 GrCachedLayer* GrLayerCache::createLayer(uint32_t pictureID,
125                                          int start, int stop,
126                                          const SkIRect& srcIR,
127                                          const SkIRect& dstIR,
128                                          const SkMatrix& initialMat,
129                                          const unsigned* key,
130                                          int keySize,
131                                          const SkPaint* paint) {
132     SkASSERT(pictureID != SK_InvalidGenID && start >= 0 && stop > 0);
133 
134     GrCachedLayer* layer = SkNEW_ARGS(GrCachedLayer, (pictureID, start, stop,
135                                                       srcIR, dstIR, initialMat,
136                                                       key, keySize, paint));
137     fLayerHash.add(layer);
138     return layer;
139 }
140 
findLayer(uint32_t pictureID,const SkMatrix & initialMat,const unsigned * key,int keySize)141 GrCachedLayer* GrLayerCache::findLayer(uint32_t pictureID, const SkMatrix& initialMat,
142                                        const unsigned* key, int keySize) {
143     SkASSERT(pictureID != SK_InvalidGenID);
144     return fLayerHash.find(GrCachedLayer::Key(pictureID, initialMat, key, keySize));
145 }
146 
findLayerOrCreate(uint32_t pictureID,int start,int stop,const SkIRect & srcIR,const SkIRect & dstIR,const SkMatrix & initialMat,const unsigned * key,int keySize,const SkPaint * paint)147 GrCachedLayer* GrLayerCache::findLayerOrCreate(uint32_t pictureID,
148                                                int start, int stop,
149                                                const SkIRect& srcIR,
150                                                const SkIRect& dstIR,
151                                                const SkMatrix& initialMat,
152                                                const unsigned* key,
153                                                int keySize,
154                                                const SkPaint* paint) {
155     SkASSERT(pictureID != SK_InvalidGenID && start >= 0 && stop > 0);
156     GrCachedLayer* layer = fLayerHash.find(GrCachedLayer::Key(pictureID, initialMat, key, keySize));
157     if (NULL == layer) {
158         layer = this->createLayer(pictureID, start, stop,
159                                   srcIR, dstIR, initialMat,
160                                   key, keySize, paint);
161     }
162 
163     return layer;
164 }
165 
tryToAtlas(GrCachedLayer * layer,const GrSurfaceDesc & desc,bool * needsRendering)166 bool GrLayerCache::tryToAtlas(GrCachedLayer* layer,
167                               const GrSurfaceDesc& desc,
168                               bool* needsRendering) {
169     SkDEBUGCODE(GrAutoValidateLayer avl(fAtlas ? fAtlas->getTexture() : NULL, layer);)
170 
171     SkASSERT(PlausiblyAtlasable(desc.fWidth, desc.fHeight));
172     SkASSERT(0 == desc.fSampleCnt);
173 
174     if (layer->locked()) {
175         // This layer is already locked
176         SkASSERT(fAtlas);
177         SkASSERT(layer->isAtlased());
178         SkASSERT(layer->rect().width() == desc.fWidth);
179         SkASSERT(layer->rect().height() == desc.fHeight);
180         *needsRendering = false;
181         return true;
182     }
183 
184     if (layer->isAtlased()) {
185         SkASSERT(fAtlas);
186         // Hooray it is still in the atlas - make sure it stays there
187         layer->setLocked(true);
188         this->incPlotLock(layer->plot()->id());
189         *needsRendering = false;
190         return true;
191     } else {
192         if (!fAtlas) {
193             this->initAtlas();
194             if (!fAtlas) {
195                 return false;
196             }
197         }
198         // Not in the atlas - will it fit?
199         GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
200         if (NULL == pictInfo) {
201             pictInfo = SkNEW_ARGS(GrPictureInfo, (layer->pictureID()));
202             fPictureHash.add(pictInfo);
203         }
204 
205         SkIPoint16 loc;
206         for (int i = 0; i < 2; ++i) { // extra pass in case we fail to add but are able to purge
207             GrPlot* plot = fAtlas->addToAtlas(&pictInfo->fPlotUsage,
208                                               desc.fWidth, desc.fHeight,
209                                               NULL, &loc);
210             // addToAtlas can allocate the backing texture
211             SkDEBUGCODE(avl.setBackingTexture(fAtlas->getTexture()));
212             if (plot) {
213 #if !GR_CACHE_HOISTED_LAYERS
214                 pictInfo->incPlotUsage(plot->id());
215 #endif
216                 // The layer was successfully added to the atlas
217                 const SkIRect bounds = SkIRect::MakeXYWH(loc.fX, loc.fY,
218                                                          desc.fWidth, desc.fHeight);
219                 layer->setTexture(fAtlas->getTexture(), bounds);
220                 layer->setPlot(plot);
221                 layer->setLocked(true);
222                 this->incPlotLock(layer->plot()->id());
223                 *needsRendering = true;
224                 return true;
225             }
226 
227             // The layer was rejected by the atlas (even though we know it is
228             // plausibly atlas-able). See if a plot can be purged and try again.
229             if (!this->purgePlot()) {
230                 break;  // We weren't able to purge any plots
231             }
232         }
233 
234         if (pictInfo->fPlotUsage.isEmpty()) {
235             fPictureHash.remove(pictInfo->fPictureID);
236             SkDELETE(pictInfo);
237         }
238     }
239 
240     return false;
241 }
242 
lock(GrCachedLayer * layer,const GrSurfaceDesc & desc,bool * needsRendering)243 bool GrLayerCache::lock(GrCachedLayer* layer, const GrSurfaceDesc& desc, bool* needsRendering) {
244     if (layer->locked()) {
245         // This layer is already locked
246         *needsRendering = false;
247         return true;
248     }
249 
250     // TODO: make the test for exact match depend on the image filters themselves
251     GrTextureProvider::ScratchTexMatch usage = GrTextureProvider::kApprox_ScratchTexMatch;
252     if (layer->fFilter) {
253         usage = GrTextureProvider::kExact_ScratchTexMatch;
254     }
255 
256     SkAutoTUnref<GrTexture> tex(fContext->textureProvider()->refScratchTexture(desc, usage));
257     if (!tex) {
258         return false;
259     }
260 
261     layer->setTexture(tex, SkIRect::MakeWH(desc.fWidth, desc.fHeight));
262     layer->setLocked(true);
263     *needsRendering = true;
264     return true;
265 }
266 
unlock(GrCachedLayer * layer)267 void GrLayerCache::unlock(GrCachedLayer* layer) {
268     SkDEBUGCODE(GrAutoValidateLayer avl(fAtlas ? fAtlas->getTexture() : NULL, layer);)
269 
270     if (NULL == layer || !layer->locked()) {
271         // invalid or not locked
272         return;
273     }
274 
275     if (layer->isAtlased()) {
276         const int plotID = layer->plot()->id();
277 
278         this->decPlotLock(plotID);
279         // At this point we could aggressively clear out un-locked plots but
280         // by delaying we may be able to reuse some of the atlased layers later.
281 #if !GR_CACHE_HOISTED_LAYERS
282         // This testing code aggressively removes the atlased layers. This
283         // can be used to separate the performance contribution of less
284         // render target pingponging from that due to the re-use of cached layers
285         GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
286         SkASSERT(pictInfo);
287 
288         pictInfo->decPlotUsage(plotID);
289 
290         if (0 == pictInfo->plotUsage(plotID)) {
291             GrAtlas::RemovePlot(&pictInfo->fPlotUsage, layer->plot());
292 
293             if (pictInfo->fPlotUsage.isEmpty()) {
294                 fPictureHash.remove(pictInfo->fPictureID);
295                 SkDELETE(pictInfo);
296             }
297         }
298 
299         layer->setPlot(NULL);
300         layer->setTexture(NULL, SkIRect::MakeEmpty());
301 #endif
302 
303     } else {
304         layer->setTexture(NULL, SkIRect::MakeEmpty());
305     }
306 
307     layer->setLocked(false);
308 }
309 
310 #ifdef SK_DEBUG
validate() const311 void GrLayerCache::validate() const {
312     int plotLocks[kNumPlotsX * kNumPlotsY];
313     memset(plotLocks, 0, sizeof(plotLocks));
314 
315     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::ConstIter iter(&fLayerHash);
316     for (; !iter.done(); ++iter) {
317         const GrCachedLayer* layer = &(*iter);
318 
319         layer->validate(fAtlas.get() ? fAtlas->getTexture() : NULL);
320 
321         const GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
322         if (!pictInfo) {
323             // If there is no picture info for this picture then all of its
324             // layers should be non-atlased.
325             SkASSERT(!layer->isAtlased());
326         }
327 
328         if (layer->plot()) {
329             SkASSERT(pictInfo);
330             SkASSERT(pictInfo->fPictureID == layer->pictureID());
331 
332             SkASSERT(pictInfo->fPlotUsage.contains(layer->plot()));
333 #if !GR_CACHE_HOISTED_LAYERS
334             SkASSERT(pictInfo->plotUsage(layer->plot()->id()) > 0);
335 #endif
336 
337             if (layer->locked()) {
338                 plotLocks[layer->plot()->id()]++;
339             }
340         }
341     }
342 
343     for (int i = 0; i < kNumPlotsX*kNumPlotsY; ++i) {
344         SkASSERT(plotLocks[i] == fPlotLocks[i]);
345     }
346 }
347 
348 class GrAutoValidateCache : ::SkNoncopyable {
349 public:
GrAutoValidateCache(GrLayerCache * cache)350     explicit GrAutoValidateCache(GrLayerCache* cache)
351         : fCache(cache) {
352         fCache->validate();
353     }
~GrAutoValidateCache()354     ~GrAutoValidateCache() {
355         fCache->validate();
356     }
357 private:
358     GrLayerCache* fCache;
359 };
360 #endif
361 
purge(uint32_t pictureID)362 void GrLayerCache::purge(uint32_t pictureID) {
363 
364     SkDEBUGCODE(GrAutoValidateCache avc(this);)
365 
366     // We need to find all the layers associated with 'picture' and remove them.
367     SkTDArray<GrCachedLayer*> toBeRemoved;
368 
369     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::Iter iter(&fLayerHash);
370     for (; !iter.done(); ++iter) {
371         if (pictureID == (*iter).pictureID()) {
372             *toBeRemoved.append() = &(*iter);
373         }
374     }
375 
376     for (int i = 0; i < toBeRemoved.count(); ++i) {
377         SkASSERT(0 == toBeRemoved[i]->uses());
378         this->unlock(toBeRemoved[i]);
379         fLayerHash.remove(GrCachedLayer::GetKey(*toBeRemoved[i]));
380         SkDELETE(toBeRemoved[i]);
381     }
382 
383     GrPictureInfo* pictInfo = fPictureHash.find(pictureID);
384     if (pictInfo) {
385         fPictureHash.remove(pictureID);
386         SkDELETE(pictInfo);
387     }
388 }
389 
purgePlot()390 bool GrLayerCache::purgePlot() {
391     SkDEBUGCODE(GrAutoValidateCache avc(this);)
392     SkASSERT(fAtlas);
393 
394     GrAtlas::PlotIter iter;
395     GrPlot* plot;
396     for (plot = fAtlas->iterInit(&iter, GrAtlas::kLRUFirst_IterOrder);
397          plot;
398          plot = iter.prev()) {
399         if (fPlotLocks[plot->id()] > 0) {
400             continue;
401         }
402 
403         this->purgePlot(plot);
404         return true;
405     }
406 
407     return false;
408 }
409 
purgePlot(GrPlot * plot)410 void GrLayerCache::purgePlot(GrPlot* plot) {
411     SkASSERT(0 == fPlotLocks[plot->id()]);
412 
413     // We need to find all the layers in 'plot' and remove them.
414     SkTDArray<GrCachedLayer*> toBeRemoved;
415 
416     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::Iter iter(&fLayerHash);
417     for (; !iter.done(); ++iter) {
418         if (plot == (*iter).plot()) {
419             *toBeRemoved.append() = &(*iter);
420         }
421     }
422 
423     for (int i = 0; i < toBeRemoved.count(); ++i) {
424         SkASSERT(0 == toBeRemoved[i]->uses());
425         SkASSERT(!toBeRemoved[i]->locked());
426 
427         uint32_t pictureIDToRemove = toBeRemoved[i]->pictureID();
428 
429         // Aggressively remove layers and, if it becomes totally uncached, delete the picture info
430         fLayerHash.remove(GrCachedLayer::GetKey(*toBeRemoved[i]));
431         SkDELETE(toBeRemoved[i]);
432 
433         GrPictureInfo* pictInfo = fPictureHash.find(pictureIDToRemove);
434         if (pictInfo) {
435 #if !GR_CACHE_HOISTED_LAYERS
436             SkASSERT(0 == pictInfo->plotUsage(plot->id()));
437 #endif
438             GrAtlas::RemovePlot(&pictInfo->fPlotUsage, plot);
439 
440             if (pictInfo->fPlotUsage.isEmpty()) {
441                 fPictureHash.remove(pictInfo->fPictureID);
442                 SkDELETE(pictInfo);
443             }
444         }
445     }
446 
447     plot->resetRects();
448 }
449 
450 #if !GR_CACHE_HOISTED_LAYERS
purgeAll()451 void GrLayerCache::purgeAll() {
452     if (!fAtlas) {
453         return;
454     }
455 
456     GrAtlas::PlotIter iter;
457     GrPlot* plot;
458     for (plot = fAtlas->iterInit(&iter, GrAtlas::kLRUFirst_IterOrder);
459          plot;
460          plot = iter.prev()) {
461         SkASSERT(0 == fPlotLocks[plot->id()]);
462 
463         this->purgePlot(plot);
464     }
465 
466     SkASSERT(0 == fPictureHash.count());
467 
468     fContext->discardRenderTarget(fAtlas->getTexture()->asRenderTarget());
469 }
470 #endif
471 
processDeletedPictures()472 void GrLayerCache::processDeletedPictures() {
473     SkTArray<SkPicture::DeletionMessage> deletedPictures;
474     fPictDeletionInbox.poll(&deletedPictures);
475 
476     for (int i = 0; i < deletedPictures.count(); i++) {
477         this->purge(deletedPictures[i].fUniqueID);
478     }
479 }
480 
481 #ifdef SK_DEVELOPER
writeLayersToDisk(const SkString & dirName)482 void GrLayerCache::writeLayersToDisk(const SkString& dirName) {
483 
484     if (fAtlas) {
485         GrTexture* atlasTexture = fAtlas->getTexture();
486         if (NULL != atlasTexture) {
487             SkString fileName(dirName);
488             fileName.append("\\atlas.png");
489 
490             atlasTexture->surfacePriv().savePixels(fileName.c_str());
491         }
492     }
493 
494     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::Iter iter(&fLayerHash);
495     for (; !iter.done(); ++iter) {
496         GrCachedLayer* layer = &(*iter);
497 
498         if (layer->isAtlased() || !layer->texture()) {
499             continue;
500         }
501 
502         SkString fileName(dirName);
503         fileName.appendf("\\%d", layer->fKey.pictureID());
504         for (int i = 0; i < layer->fKey.keySize(); ++i) {
505             fileName.appendf("-%d", layer->fKey.key()[i]);
506         }
507         fileName.appendf(".png");
508 
509         layer->texture()->surfacePriv().savePixels(fileName.c_str());
510     }
511 }
512 #endif
513