Add support for hoisting layers in pictures drawn with a matrix

src/gpu/GrLayerHoister.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrLayerCache.h"
 #include "GrLayerHoister.h"
 #include "GrRecordReplaceDraw.h"
 
 #include "SkCanvas.h"
 #include "SkGrPixelRef.h"
 #include "SkLayerInfo.h"
 #include "SkRecordDraw.h"
 #include "SkSurface.h"
 
 // Create the layer information for the hoisted layer and secure the
 // required texture/render target resources.
 static void prepare_for_hoisting(GrLayerCache* layerCache, 
                                  const SkPicture* topLevelPicture,
+                                 const SkMatrix& matrix,
                                  const SkLayerInfo::BlockInfo& info,
                                  const SkIRect& layerRect,
                                  SkTDArray<GrHoistedLayer>* needRendering,
                                  SkTDArray<GrHoistedLayer>* recycled,
                                  bool attemptToAtlas,
                                  int numSamples) {
     const SkPicture* pict = info.fPicture ? info.fPicture : topLevelPicture;
 
-    SkMatrix combined = SkMatrix::Concat(info.fPreMat, info.fLocalMat);
+    SkMatrix combined = matrix;
+    combined.preConcat(info.fPreMat);
+    combined.preConcat(info.fLocalMat);
 
     GrCachedLayer* layer = layerCache->findLayerOrCreate(pict->uniqueID(),
                                                          info.fSaveLayerOpID,
                                                          info.fRestoreOpID,
                                                          layerRect,
                                                          combined,
                                                          info.fPaint);
     GrSurfaceDesc desc;
     desc.fFlags = kRenderTarget_GrSurfaceFlag;
     desc.fWidth = layerRect.width();
@@ skipping 25 matching lines @@
         hl = needRendering->append();
     } else {
         hl = recycled->append();
     }
     
     layerCache->addUse(layer);
     hl->fLayer = layer;
     hl->fPicture = pict;
     hl->fOffset = SkIPoint::Make(layerRect.fLeft, layerRect.fTop);
     hl->fLocalMat = info.fLocalMat;
-    hl->fPreMat = info.fPreMat;
+    hl->fPreMat = matrix;
+    hl->fPreMat.preConcat(info.fPreMat);
 }
 
 // Atlased layers must be small enough to fit in the atlas, not have a
 // paint with an image filter and be neither nested nor nesting.
 // TODO: allow leaf nested layers to appear in the atlas.
 void GrLayerHoister::FindLayersToAtlas(GrContext* context,
                                        const SkPicture* topLevelPicture,
+                                       const SkMatrix& initialMat,
                                        const SkRect& query,
                                        SkTDArray<GrHoistedLayer>* atlased,
                                        SkTDArray<GrHoistedLayer>* recycled,
                                        int numSamples) {
     if (0 != numSamples) {
         // MSAA layers are currently never atlased
         return;
     }
 
     GrLayerCache* layerCache = context->getLayerCache();
@@ skipping 18 matching lines @@
         const SkLayerInfo::BlockInfo& info = topLevelGPUData->block(i);
 
         // TODO: ignore perspective projected layers here?
         bool disallowAtlasing = info.fHasNestedLayers || info.fIsNested ||
                                 (info.fPaint && info.fPaint->getImageFilter());
 
         if (disallowAtlasing) {
             continue;
         }
 
-        SkRect layerRect = info.fBounds;
+        SkRect layerRect;
+        initialMat.mapRect(&layerRect, info.fBounds);
         if (!layerRect.intersect(query)) {
             continue;
         }
 
-        SkIRect ir;
-        layerRect.roundOut(&ir);
+        const SkIRect ir = layerRect.roundOut();
 
         if (!GrLayerCache::PlausiblyAtlasable(ir.width(), ir.height())) {
             continue;
         }
 
-        prepare_for_hoisting(layerCache, topLevelPicture, info, ir, atlased, recycled, true, 0);
+        prepare_for_hoisting(layerCache, topLevelPicture, initialMat,
+                             info, ir, atlased, recycled, true, 0);
     }
 
 }
 
 void GrLayerHoister::FindLayersToHoist(GrContext* context,
                                        const SkPicture* topLevelPicture,
+                                       const SkMatrix& initialMat,
                                        const SkRect& query,
                                        SkTDArray<GrHoistedLayer>* needRendering,
                                        SkTDArray<GrHoistedLayer>* recycled,
                                        int numSamples) {
     GrLayerCache* layerCache = context->getLayerCache();
 
     layerCache->processDeletedPictures();
 
     SkPicture::AccelData::Key key = SkLayerInfo::ComputeKey();
 
     const SkPicture::AccelData* topLevelData = topLevelPicture->EXPERIMENTAL_getAccelData(key);
     if (!topLevelData) {
         return;
     }
 
     const SkLayerInfo *topLevelGPUData = static_cast<const SkLayerInfo*>(topLevelData);
     if (0 == topLevelGPUData->numBlocks()) {
         return;
     }
 
     // Find and prepare for hoisting all the layers that intersect the query rect
     for (int i = 0; i < topLevelGPUData->numBlocks(); ++i) {
         const SkLayerInfo::BlockInfo& info = topLevelGPUData->block(i);
         if (info.fIsNested) {
             // Parent layers are currently hoisted while nested layers are not.
             continue;
         }
 
-        SkRect layerRect = info.fBounds;
+        SkRect layerRect;
+        initialMat.mapRect(&layerRect, info.fBounds);
         if (!layerRect.intersect(query)) {
             continue;
         }
 
-        SkIRect ir;
-        layerRect.roundOut(&ir);
+        const SkIRect ir = layerRect.roundOut();
 
-        prepare_for_hoisting(layerCache, topLevelPicture, info, ir, 
+        prepare_for_hoisting(layerCache, topLevelPicture, initialMat, info, ir,
                              needRendering, recycled, false, numSamples);
     }
 }
 
 static void wrap_texture(GrTexture* texture, int width, int height, SkBitmap* result) {
     SkImageInfo info = SkImageInfo::MakeN32Premul(width, height);
     result->setInfo(info);
     result->setPixelRef(SkNEW_ARGS(SkGrPixelRef, (info, texture)))->unref();
 }
 
@@ skipping 143 matching lines @@
 void GrLayerHoister::PurgeCache(GrContext* context) {
 #if !GR_CACHE_HOISTED_LAYERS
     GrLayerCache* layerCache = context->getLayerCache();
 
     // This code completely clears out the atlas. It is required when
     // caching is disabled so the atlas doesn't fill up and force more
     // free floating layers
     layerCache->purgeAll();
 #endif
 }