1 files changed, 23 insertions, 25 deletions

diff --git a/src/gpu/GrClipMaskCache.h b/src/gpu/GrClipMaskCache.h
index 6722d70362..9a091c4b3a 100644
--- a/src/gpu/GrClipMaskCache.h
+++ b/src/gpu/GrClipMaskCache.h
@@ -31,18 +31,22 @@ public:
         }
     }
 
-    bool canReuse(const SkClipStack& clip, const GrIRect& devBounds) {
+    bool canReuse(int32_t clipGenID, const SkIRect& bounds) {
 
-        if (fStack.empty()) {
-            GrAssert(false);
+        SkASSERT(clipGenID != SkClipStack::kWideOpenGenID);
+        SkASSERT(clipGenID != SkClipStack::kEmptyGenID);
+
+        if (SkClipStack::kInvalidGenID == clipGenID) {
             return false;
         }
 
         GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
 
+        // We could reuse the mask if bounds is a subset of last bounds. We'd have to communicate
+        // an offset to the caller.
         if (back->fLastMask.texture() &&
-            back->fLastBound == devBounds &&
-            clip == back->fLastClip) {
+            back->fLastBound == bounds &&
+            back->fLastClipGenID == clipGenID) {
             return true;
         }
 
@@ -79,17 +83,13 @@ public:
         }
     }
 
-    void getLastClip(SkClipStack* clip) const {
+    int32_t getLastClipGenID() const {
 
         if (fStack.empty()) {
-            GrAssert(false);
-            clip->reset();
-            return;
+            return SkClipStack::kInvalidGenID;
         }
 
-        GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
-
-        *clip = back->fLastClip;
+        return ((GrClipStackFrame*) fStack.back())->fLastClipGenID;
     }
 
     GrTexture* getLastMask() {
@@ -116,7 +116,7 @@ public:
         return back->fLastMask.texture();
     }
 
-    void acquireMask(const SkClipStack& clip,
+    void acquireMask(int32_t clipGenID,
                      const GrTextureDesc& desc,
                      const GrIRect& bound) {
 
@@ -127,7 +127,7 @@ public:
 
         GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
 
-        back->acquireMask(fContext, clip, desc, bound);
+        back->acquireMask(fContext, clipGenID, desc, bound);
     }
 
     int getLastMaskWidth() const {
@@ -193,20 +193,19 @@ public:
         }
     }
 
-protected:
 private:
     struct GrClipStackFrame {
 
         GrClipStackFrame() {
-            reset();
+            this->reset();
         }
 
         void acquireMask(GrContext* context,
-                         const SkClipStack& clip,
+                         int32_t clipGenID,
                          const GrTextureDesc& desc,
                          const GrIRect& bound) {
 
-            fLastClip = clip;
+            fLastClipGenID = clipGenID;
 
             fLastMask.set(context, desc);
 
@@ -214,7 +213,7 @@ private:
         }
 
         void reset () {
-            fLastClip.reset();
+            fLastClipGenID = SkClipStack::kInvalidGenID;
 
             GrTextureDesc desc;
 
@@ -222,13 +221,12 @@ private:
             fLastBound.setEmpty();
         }
 
-        SkClipStack             fLastClip;
-        // The mask's width & height values are used in setupDrawStateAAClip to
-        // correctly scale the uvs for geometry drawn with this mask
+        int32_t                 fLastClipGenID;
+        // The mask's width & height values are used by GrClipMaskManager to correctly scale the
+        // texture coords for the geometry drawn with this mask.
         GrAutoScratchTexture    fLastMask;
-        // fLastBound stores the bounding box of the clip mask in canvas
-        // space. The left and top fields are used to offset the uvs for
-        // geometry drawn with this mask (in setupDrawStateAAClip)
+        // fLastBound stores the bounding box of the clip mask in clip-stack space. This rect is
+        // used by GrClipMaskManager to position a rect and compute texture coords for the mask.
         GrIRect                 fLastBound;
     };