Implement a persistent uniqueID-based cache for SkImageFilter.

src/core/SkCanvas.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkCanvas.h"
 #include "SkBitmapDevice.h"
@@ skipping 1116 matching lines @@
         SkImageFilter* filter = paint->getImageFilter();
         SkIPoint pos = { x - iter.getX(), y - iter.getY() };
         if (filter && !dstDev->canHandleImageFilter(filter)) {
             SkDeviceImageFilterProxy proxy(dstDev);
             SkBitmap dst;
             SkIPoint offset = SkIPoint::Make(0, 0);
             const SkBitmap& src = srcDev->accessBitmap(false);
             SkMatrix matrix = *iter.fMatrix;
             matrix.postTranslate(SkIntToScalar(-pos.x()), SkIntToScalar(-pos.y()));
             SkIRect clipBounds = SkIRect::MakeWH(srcDev->width(), srcDev->height());
-            SkImageFilter::Cache* cache = SkImageFilter::GetExternalCache();
-            SkAutoUnref aur(NULL);
-            if (!cache) {
-                cache = SkImageFilter::Cache::Create();
-                aur.reset(cache);
-            }
-            SkImageFilter::Context ctx(matrix, clipBounds, cache);
+            SkAutoTUnref<SkImageFilter::UniqueIDCache> cache(dstDev->getImageFilterCache());
+            SkImageFilter::Context ctx(matrix, clipBounds, cache.get());
             if (filter->filterImage(&proxy, src, ctx, &dst, &offset)) {
                 SkPaint tmpUnfiltered(*paint);
                 tmpUnfiltered.setImageFilter(NULL);
                 dstDev->drawSprite(iter, dst, pos.x() + offset.x(), pos.y() + offset.y(),
                                    tmpUnfiltered);
             }
         } else {
             dstDev->drawDevice(iter, srcDev, pos.x(), pos.y(), *paint);
         }
     }
@@ skipping 18 matching lines @@
         paint = &looper.paint();
         SkImageFilter* filter = paint->getImageFilter();
         SkIPoint pos = { x - iter.getX(), y - iter.getY() };
         if (filter && !iter.fDevice->canHandleImageFilter(filter)) {
             SkDeviceImageFilterProxy proxy(iter.fDevice);
             SkBitmap dst;
             SkIPoint offset = SkIPoint::Make(0, 0);
             SkMatrix matrix = *iter.fMatrix;
             matrix.postTranslate(SkIntToScalar(-pos.x()), SkIntToScalar(-pos.y()));
             SkIRect clipBounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
-            SkImageFilter::Cache* cache = SkImageFilter::GetExternalCache();
-            SkAutoUnref aur(NULL);
-            if (!cache) {
-                cache = SkImageFilter::Cache::Create();
-                aur.reset(cache);
-            }
-            SkImageFilter::Context ctx(matrix, clipBounds, cache);
+            SkAutoTUnref<SkImageFilter::UniqueIDCache> cache(iter.fDevice->getImageFilterCache());
+            SkImageFilter::Context ctx(matrix, clipBounds, cache.get());
             if (filter->filterImage(&proxy, bitmap, ctx, &dst, &offset)) {
                 SkPaint tmpUnfiltered(*paint);
                 tmpUnfiltered.setImageFilter(NULL);
                 iter.fDevice->drawSprite(iter, dst, pos.x() + offset.x(), pos.y() + offset.y(),
                                          tmpUnfiltered);
             }
         } else {
             iter.fDevice->drawSprite(iter, bitmap, pos.x(), pos.y(), *paint);
         }
     }
@@ skipping 1296 matching lines @@
     if (!supported_for_raster_canvas(info)) {
         return NULL;
     }
 
     SkBitmap bitmap;
     if (!bitmap.installPixels(info, pixels, rowBytes)) {
         return NULL;
     }
     return SkNEW_ARGS(SkCanvas, (bitmap));
 }