apply imagefilter to all draw calls

Review URL: https://codereview.appspot.com/5856048

git-svn-id: http://skia.googlecode.com/svn/trunk@3476 2bbb7eff-a529-9590-31e7-b0007b416f81

3 files changed, 23 insertions, 10 deletions

diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
index 7ad88f64cc..5224217fdc 100644
--- a/include/core/SkCanvas.h
+++ b/include/core/SkCanvas.h
@@ -977,6 +977,7 @@ private:
     void updateDeviceCMCache();
 
     friend class SkDrawIter;    // needs setupDrawForLayerDevice()
+    friend class AutoDrawLooper;
 
     SkDevice* createLayerDevice(SkBitmap::Config, int width, int height,
                                 bool isOpaque);
@@ -992,9 +993,10 @@ private:
     void internalDrawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
                                 const SkRect& dst, const SkPaint* paint);
     void internalDrawPaint(const SkPaint& paint);
+    int internalSaveLayer(const SkRect* bounds, const SkPaint* paint,
+                          SaveFlags, bool justForImageFilter);
+    void internalDrawDevice(SkDevice*, int x, int y, const SkPaint*);
 
-
-    void drawDevice(SkDevice*, int x, int y, const SkPaint*);
     // shared by save() and saveLayer()
     int internalSave(SaveFlags flags);
     void internalRestore();
diff --git a/include/core/SkDevice.h b/include/core/SkDevice.h
index 3303981c74..db9c542ada 100644
--- a/include/core/SkDevice.h
+++ b/include/core/SkDevice.h
@@ -321,13 +321,22 @@ protected:
     virtual bool allowImageFilter(SkImageFilter*);
 
     /**
-     *  Override and return true for filters that the device handles
-     *  intrinsically. Returning false means call the filter.
-     *  Default impl returns false. This will only be called if allowImageFilter()
-     *  returned true.
+     *  Override and return true for filters that the device can handle
+     *  intrinsically. Doing so means that SkCanvas will pass-through this
+     *  filter to drawSprite and drawDevice (and potentially filterImage).
+     *  Returning false means the SkCanvas will have apply the filter itself,
+     *  and just pass the resulting image to the device.
      */
-    virtual bool filterImage(SkImageFilter*, const SkBitmap& src,
-                             const SkMatrix& ctm,
+    virtual bool canHandleImageFilter(SkImageFilter*);
+
+    /**
+     *  Related (but not required) to canHandleImageFilter, this method returns
+     *  true if the device could apply the filter to the src bitmap and return
+     *  the result (and updates offset as needed).
+     *  If the device does not recognize or support this filter,
+     *  it just returns false and leaves result and offset unchanged.
+     */
+    virtual bool filterImage(SkImageFilter*, const SkBitmap&, const SkMatrix&,
                              SkBitmap* result, SkIPoint* offset);
 
     // This is equal kBGRA_Premul_Config8888 or kRGBA_Premul_Config8888 if
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index 7d7c1404f1..1b282d2e32 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -40,14 +40,16 @@ class SK_API SkImageFilter : public SkFlattenable {
 public:
     class Proxy {
     public:
+        virtual ~Proxy() {};
+
         virtual SkDevice* createDevice(int width, int height) = 0;
-        
+        // returns true if the proxy can handle this filter natively
+        virtual bool canHandleImageFilter(SkImageFilter*) = 0;
         // returns true if the proxy handled the filter itself. if this returns
         // false then the filter's code will be called.
         virtual bool filterImage(SkImageFilter*, const SkBitmap& src,
                                  const SkMatrix& ctm,
                                  SkBitmap* result, SkIPoint* offset) = 0;
-        virtual ~Proxy() {};
     };
 
     /**