More general version of image filtering; reworked to be robust and easier to SSE

include/core/SkBitmap.h

Index: include/core/SkBitmap.h
diff --git a/include/core/SkBitmap.h b/include/core/SkBitmap.h
index 887169ccb522c2820c8c2f0ff3f78e454d0d00cf..2bfa19d5b253076dd5d9922f856d765db9e21fdc 100644
--- a/include/core/SkBitmap.h
+++ b/include/core/SkBitmap.h
@@ -538,6 +538,11 @@ public:
         by calling copyTo().
      */
     bool canCopyTo(Config newConfig) const;
+    
+    /** Make a scaled copy of this bitmap into the provided destination.
+      */
+      
+    void scale(SkBitmap *dst) const;

[reed1, 2013/07/09 14:25:47]

1. Need to document what parts of dst need to be set, and which parts will be
overwritten
2. Do we need to make a public method for this. Seems like just a 4 line helper
for drawBitmap / matrix.

[humper, 2013/07/09 14:47:26]

1) Yep, will do.

2) It's not a helper; this directly scales the bitmap with proper HQ resampling,
bypassing the entire draw pipeline.

On 2013/07/09 14:25:47, reed1 wrote:

[reed1, 2013/07/09 15:01:01]

Does it generate diff results from just setting up a paint correctly and calling
draw? If not, then I call it a helper.

I'm not against it per-se, but any additional public API should be well
justified (especially one that diverts clients from our higher-level APIs like
canvas/surface/image, which are more future-proofed).

 
     /**
      *  DEPRECATED -- will be replaced with API on SkPaint