[GPU] Use view matrix + rect to implement subrect for drawBitmap when there is a mask filter and ble

src/gpu/SkGpuDevice.cpp

Index: src/gpu/SkGpuDevice.cpp
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index 063509a5a4d6b3d4e27a81f7a852d7c140030a40..062ef54505fbef52f88d549087bc62889ddfa3f2 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -1117,26 +1117,23 @@ void SkGpuDevice::drawBitmapCommon(const SkDraw& draw,
         SkBitmap        tmp;    // subset of bitmap, if necessary
         const SkBitmap* bitmapPtr = &bitmap;
         if (NULL != srcRectPtr) {

[robertphillips, 2013/11/22 18:59:37]

Maybe: "In bleed mode we position the bitmap based on the src rect which is
already accounted for in 'm' and 'srcRect'. In clamp mode we need to chop out
the desired portion of the bitmap"

-            SkIRect iSrc;
-            srcRect.roundOut(&iSrc);
+            // In bleed mode we simply want to position the bitmap based on the src rect. Matrix m
+            // and srcRect already accounts for this.
+            if (!(SkCanvas::kBleed_DrawBitmapRectFlag & flags)) {
+                SkIRect iSrc;
+                srcRect.roundOut(&iSrc);
 
-            SkPoint offset = SkPoint::Make(SkIntToScalar(iSrc.fLeft),
-                                           SkIntToScalar(iSrc.fTop));
+                SkPoint offset = SkPoint::Make(SkIntToScalar(iSrc.fLeft),
+                                               SkIntToScalar(iSrc.fTop));
 
-            if (SkCanvas::kBleed_DrawBitmapRectFlag & flags) {
-                // In bleed mode we want to expand the src rect on all sides
-                // but stay within the bitmap bounds
-                SkIRect iClampRect = SkIRect::MakeWH(bitmap.width(), bitmap.height());
-                clamped_unit_outset_with_offset(&iSrc, &offset, iClampRect);
-            }
-
-            if (!bitmap.extractSubset(&tmp, iSrc)) {
-                return;     // extraction failed
+                if (!bitmap.extractSubset(&tmp, iSrc)) {
+                    return;     // extraction failed
+                }
+                bitmapPtr = &tmp;
+                srcRect.offset(-offset.fX, -offset.fY);
+                // The source rect has changed so update the matrix
+                newM.preTranslate(offset.fX, offset.fY);
             }
-            bitmapPtr = &tmp;
-            srcRect.offset(-offset.fX, -offset.fY);
-            // The source rect has changed so update the matrix
-            newM.preTranslate(offset.fX, offset.fY);
         }
 
         SkPaint paintWithTexture(paint);