Improvements/additions to SkImageCache/SkLazyPixelRef.

tools/PictureRenderingFlags.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "PictureRenderingFlags.h"
 
 #include "CopyTilesRenderer.h"
 #include "PictureRenderer.h"
 #include "picture_utils.h"
 
+#include "SkBitmapFactory.h"
+#include "SkData.h"
 #include "SkFlags.h"
+#include "SkImage.h"
+#include "SkImageDecoder.h"
+#include "SkLruImageCache.h"
+#include "SkPurgeableImageCache.h"
+#include "SkString.h"
 
 // Alphabetized list of flags used by this file or bench_ and render_pictures.
 DEFINE_string(bbh, "none", "bbhType [width height]: Set the bounding box hierarchy type to "
               "be used. Accepted values are: none, rtree, grid. "
               "Not compatible with --pipe. With value "
               "'grid', width and height must be specified. 'grid' can "
               "only be used with modes tile, record, and "
               "playbackCreation.");
 // Although this config does not support all the same options as gm, the names should be kept
 // consistent.
@@ skipping 25 matching lines @@
               "\tSkPicturePlayback.\n"
               "rerecord: (Only in render_pictures) Record the picture as a new skp,\n"
               "\twith the bitmaps PNG encoded.\n");
 DEFINE_int32(multi, 1, "Set the number of threads for multi threaded drawing. "
              "If > 1, requires tiled rendering.");
 DEFINE_bool(pipe, false, "Use SkGPipe rendering. Currently incompatible with \"mode\".");
 DEFINE_string(r, "", "skp files or directories of skp files to process.");
 DEFINE_double(scale, 1, "Set the scale factor.");
 DEFINE_string(tiles, "", "Used with --mode copyTile to specify number of tiles per larger tile "
               "in the x and y directions.");
+DEFINE_bool(useVolatileCache, false, "Use a volatile cache for deferred image decoding pixels. "
+            "Only meaningful if --deferImageDecoding is set to true and the platform has an "
+            "implementation.");
 DEFINE_string(viewport, "", "width height: Set the viewport.");
 
 sk_tools::PictureRenderer* parseRenderer(SkString& error, PictureTool tool) {
     error.reset();
 
     if (FLAGS_multi <= 0) {
         error.printf("--multi must be > 0, was %i", FLAGS_multi);
         return NULL;
     }
 
@@ skipping 231 matching lines @@
         if (FLAGS_pipe && sk_tools::PictureRenderer::kNone_BBoxHierarchyType != bbhType) {
             error.printf("--pipe and --bbh cannot be used together\n");
             return NULL;
         }
     }
     renderer->setBBoxHierarchyType(bbhType);
     renderer->setScaleFactor(SkDoubleToScalar(FLAGS_scale));
 
     return renderer.detach();
 }
+
+SkLruImageCache gLruImageCache(1024*1024);
+
+// Simple cache selector to choose between a purgeable cache for large images and the standard one
+// for smaller images.
+class MyCacheSelector : public SkBitmapFactory::CacheSelector {
+
+public:
+    MyCacheSelector() {
+        fPurgeableImageCache = SkPurgeableImageCache::Create();
+    }
+
+    ~MyCacheSelector() {
+        SkSafeUnref(fPurgeableImageCache);
+    }
+
+    virtual SkImageCache* selectCache(const SkImage::Info& info) SK_OVERRIDE {
+        if (info.fWidth * info.fHeight > 32 * 1024 && fPurgeableImageCache != NULL) {
+            return fPurgeableImageCache;
+        }
+        return &gLruImageCache;
+    }
+private:
+    SkImageCache* fPurgeableImageCache;
+};
+
+static MyCacheSelector gCacheSelector;
+static SkBitmapFactory gFactory(&SkImageDecoder::DecodeMemoryToTarget);
+
+bool lazy_decode_bitmap(const void* buffer, size_t size, SkBitmap* bitmap);
+bool lazy_decode_bitmap(const void* buffer, size_t size, SkBitmap* bitmap) {
+    void* copiedBuffer = sk_malloc_throw(size);
+    memcpy(copiedBuffer, buffer, size);
+    SkAutoDataUnref data(SkData::NewFromMalloc(copiedBuffer, size));
+
+    static bool gOnce;
+    if (!gOnce) {
+        // Only use the cache selector if there is a purgeable image cache to use for large
+        // images.
+        if (FLAGS_useVolatileCache && SkAutoTUnref<SkImageCache>(
+                SkPurgeableImageCache::Create()).get() != NULL) {
+            gFactory.setCacheSelector(&gCacheSelector);
+        } else {
+            gFactory.setImageCache(&gLruImageCache);
+        }
+        gOnce = true;
+    }
+    return gFactory.installPixelRef(data, bitmap);
+}