quick-rejects based on xfermode, using SkPaint::nothingToDraw()

git-svn-id: http://skia.googlecode.com/svn/trunk@2402 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 4 insertions, 0 deletions

diff --git a/include/core/SkPaint.h b/include/core/SkPaint.h
index 7f3f0be223..4785baa6f1 100644
--- a/include/core/SkPaint.h
+++ b/include/core/SkPaint.h
@@ -865,6 +865,10 @@ private:
     const SkRect& computeStrokeFastBounds(const SkRect& orig,
                                           SkRect* storage) const;
 
+    // returns true if the paint's settings (e.g. xfermode + alpha) resolve to
+    // mean that we need not draw at all (e.g. SrcOver + 0-alpha)
+    bool nothingToDraw() const;
+
     enum {
         kCanonicalTextSizeForPaths = 64
     };