Move clip off of draw target

BUG=skia:

Review URL: https://codereview.chromium.org/947443003

4 files changed, 195 insertions, 69 deletions

diff --git a/include/core/SkRect.h b/include/core/SkRect.h
index 06f8abe0e4..69c2dc9cef 100644
--- a/include/core/SkRect.h
+++ b/include/core/SkRect.h
@@ -11,6 +11,8 @@
 #include "SkPoint.h"
 #include "SkSize.h"
 
+struct SkRect;
+
 /** \struct SkIRect
 
     SkIRect holds four 32 bit integer coordinates for a rectangle
@@ -244,6 +246,10 @@ struct SK_API SkIRect {
                 fRight >= r.fRight && fBottom >= r.fBottom;
     }
 
+    /** Returns true if the specified rectangle r is inside or equal to this rectangle.
+    */
+    bool contains(const SkRect& r) const;
+
     /** Return true if this rectangle contains the specified rectangle.
         For speed, this method does not check if either this or the specified
         rectangles are empty, and if either is, its return value is undefined.
@@ -880,4 +886,10 @@ public:
     void dumpHex() const { this->dump(true); }
 };
 
+inline bool SkIRect::contains(const SkRect& r) const {
+    return  !r.isEmpty() && !this->isEmpty() &&     // check for empties
+            (SkScalar)fLeft <= r.fLeft && (SkScalar)fTop <= r.fTop &&
+            (SkScalar)fRight >= r.fRight && (SkScalar)fBottom >= r.fBottom;
+}
+
 #endif
diff --git a/include/gpu/GrClip.h b/include/gpu/GrClip.h
new file mode 100644
index 0000000000..f07a9749ca
--- /dev/null
+++ b/include/gpu/GrClip.h
@@ -0,0 +1,175 @@
+/*
+ * Copyright 2010 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrClip_DEFINED
+#define GrClip_DEFINED
+
+#include "SkClipStack.h"
+#include "GrSurface.h"
+
+struct SkIRect;
+
+/**
+ * GrClip encapsulates the information required to construct the clip
+ * masks. 'A GrClip is either wide open, just an IRect, just a Rect(TODO), or a full clipstack.
+ * If the clip is a clipstack than the origin is used to translate the stack with
+ * respect to device coordinates. This allows us to use a clip stack that is
+ * specified for a root device with a layer device that is restricted to a subset
+ * of the original canvas. For other clip types the origin will always be (0,0).
+ *
+ * NOTE: GrClip *must* point to a const clipstack
+ */
+class GrClip : SkNoncopyable {
+public:
+    GrClip() : fClipType(kWideOpen_ClipType) {}
+    GrClip(const SkIRect& rect) : fClipType(kIRect_ClipType) {
+        fClip.fIRect = rect;
+    }
+    ~GrClip() { this->reset(); }
+
+    const GrClip& operator=(const GrClip& other) {
+        this->reset();
+        fClipType = other.fClipType;
+        switch (other.fClipType) {
+            default:
+                SkFAIL("Incomplete Switch\n");
+            case kWideOpen_ClipType:
+                break;
+            case kClipStack_ClipType:
+                fClip.fClipStack.fStack = SkRef(other.clipStack());
+                fClip.fClipStack.fOrigin = other.origin();
+                break;
+            case kIRect_ClipType:
+                fClip.fIRect = other.irect();
+                break;
+        }
+        return *this;
+    }
+
+    bool operator==(const GrClip& other) const {
+        if (this->clipType() != other.clipType()) {
+            return false;
+        }
+
+        switch (fClipType) {
+            default:
+                SkFAIL("Incomplete Switch\n");
+                return false;
+            case kWideOpen_ClipType:
+                return true;
+            case kClipStack_ClipType:
+                if (this->origin() != other.origin()) {
+                    return false;
+                }
+
+                if (this->clipStack() && other.clipStack()) {
+                    return *this->clipStack() == *other.clipStack();
+                } else {
+                    return this->clipStack() == other.clipStack();
+                }
+                break;
+            case kIRect_ClipType:
+                return this->irect() == other.irect();
+                break;
+        }
+    }
+
+    bool operator!=(const GrClip& other) const {
+        return !(*this == other);
+    }
+
+    const SkClipStack* clipStack() const {
+        SkASSERT(kClipStack_ClipType == fClipType);
+        return fClip.fClipStack.fStack;
+    }
+
+    void setClipStack(const SkClipStack* clipStack, const SkIPoint* origin = NULL) {
+        if (clipStack->isWideOpen()) {
+            fClipType = kWideOpen_ClipType;
+        } else {
+            fClipType = kClipStack_ClipType;
+            fClip.fClipStack.fStack = SkRef(clipStack);
+            if (origin) {
+                fClip.fClipStack.fOrigin = *origin;
+            } else {
+                fClip.fClipStack.fOrigin.setZero();
+            }
+        }
+    }
+
+    const SkIRect& irect() const {
+        SkASSERT(kIRect_ClipType == fClipType);
+        return fClip.fIRect;
+    }
+
+    void reset() {
+        if (kClipStack_ClipType == fClipType) {
+            fClip.fClipStack.fStack->unref();
+            fClip.fClipStack.fStack = NULL;
+        }
+        fClipType = kWideOpen_ClipType;
+    }
+
+    const SkIPoint& origin() const {
+        SkASSERT(kClipStack_ClipType == fClipType);
+        return fClip.fClipStack.fOrigin;
+    }
+
+    bool isWideOpen(const SkRect& rect) const {
+        return (kWideOpen_ClipType == fClipType) ||
+               (kClipStack_ClipType == fClipType && this->clipStack()->isWideOpen()) ||
+               (kIRect_ClipType == fClipType && this->irect().contains(rect));
+    }
+
+    bool isWideOpen(const SkIRect& rect) const {
+        return (kWideOpen_ClipType == fClipType) ||
+               (kClipStack_ClipType == fClipType && this->clipStack()->isWideOpen()) ||
+               (kIRect_ClipType == fClipType && this->irect().contains(rect));
+    }
+
+    bool isWideOpen() const {
+        return (kWideOpen_ClipType == fClipType) ||
+               (kClipStack_ClipType == fClipType && this->clipStack()->isWideOpen());
+    }
+
+    void getConservativeBounds(const GrSurface* surface,
+                               SkIRect* devResult,
+                               bool* isIntersectionOfRects = NULL) const {
+        this->getConservativeBounds(surface->width(), surface->height(),
+                                    devResult, isIntersectionOfRects);
+    }
+
+    void getConservativeBounds(int width, int height,
+                               SkIRect* devResult,
+                               bool* isIntersectionOfRects = NULL) const;
+
+    static const GrClip& WideOpen() {
+        static GrClip clip;
+        return clip;
+    }
+
+    enum ClipType {
+        kClipStack_ClipType,
+        kWideOpen_ClipType,
+        kIRect_ClipType,
+    };
+
+    ClipType clipType() const { return fClipType; }
+
+private:
+    union Clip {
+        struct ClipStack {
+            const SkClipStack* fStack;
+            SkIPoint fOrigin;
+        } fClipStack;
+        SkIRect fIRect;
+    } fClip;
+
+    ClipType fClipType;
+};
+
+#endif
diff --git a/include/gpu/GrClipData.h b/include/gpu/GrClipData.h
deleted file mode 100644
index bb7101d8a6..0000000000
--- a/include/gpu/GrClipData.h
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * Copyright 2010 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef GrClip_DEFINED
-#define GrClip_DEFINED
-
-#include "SkClipStack.h"
-#include "GrSurface.h"
-
-struct SkIRect;
-
-/**
- * GrClipData encapsulates the information required to construct the clip
- * masks. 'fOrigin' is only non-zero when saveLayer has been called
- * with an offset bounding box. The clips in 'fClipStack' are in
- * device coordinates (i.e., they have been translated by -fOrigin w.r.t.
- * the canvas' device coordinates).
- */
-class GrClipData : SkNoncopyable {
-public:
-    SkAutoTUnref<const SkClipStack>  fClipStack;
-    SkIPoint                         fOrigin;
-
-    GrClipData()
-        : fClipStack(NULL) {
-        fOrigin.setZero();
-    }
-
-    bool operator==(const GrClipData& other) const {
-        if (fOrigin != other.fOrigin) {
-            return false;
-        }
-
-        if (fClipStack && other.fClipStack) {
-            return *fClipStack == *other.fClipStack;
-        }
-
-        return fClipStack == other.fClipStack;
-    }
-
-    bool operator!=(const GrClipData& other) const {
-        return !(*this == other);
-    }
-
-    void getConservativeBounds(const GrSurface* surface,
-                               SkIRect* devResult,
-                               bool* isIntersectionOfRects = NULL) const {
-        this->getConservativeBounds(surface->width(), surface->height(),
-                                    devResult, isIntersectionOfRects);
-    }
-
-    void getConservativeBounds(int width, int height,
-                               SkIRect* devResult,
-                               bool* isIntersectionOfRects = NULL) const;
-};
-
-#endif
diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 846cd0f111..2433b89189 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -8,7 +8,7 @@
 #ifndef GrContext_DEFINED
 #define GrContext_DEFINED
 
-#include "GrClipData.h"
+#include "GrClip.h"
 #include "GrColor.h"
 #include "GrPaint.h"
 #include "GrPathRendererChain.h"
@@ -367,13 +367,13 @@ public:
      * Gets the current clip.
      * @return the current clip.
      */
-    const GrClipData* getClip() const { return fClip; }
+    const GrClip* getClip() const { return fClip; }
 
     /**
      * Sets the clip.
      * @param clipData  the clip to set.
      */
-    void setClip(const GrClipData* clipData) { fClip = clipData; }
+    void setClip(const GrClip* clipData) { fClip = clipData; }
 
     ///////////////////////////////////////////////////////////////////////////
     // Draws
@@ -680,7 +680,7 @@ public:
         AutoClip(GrContext* context, InitialClip SkDEBUGCODE(initialState))
         : fContext(context) {
             SkASSERT(kWideOpen_InitialClip == initialState);
-            fNewClipData.fClipStack.reset(SkRef(&fNewClipStack));
+            fNewClipData.setClipStack(&fNewClipStack);
 
             fOldClip = context->getClip();
             context->setClip(&fNewClipData);
@@ -689,7 +689,7 @@ public:
         AutoClip(GrContext* context, const SkRect& newClipRect)
         : fContext(context)
         , fNewClipStack(newClipRect) {
-            fNewClipData.fClipStack.reset(SkRef(&fNewClipStack));
+            fNewClipData.setClipStack(&fNewClipStack);
 
             fOldClip = fContext->getClip();
             fContext->setClip(&fNewClipData);
@@ -702,10 +702,10 @@ public:
         }
     private:
         GrContext*        fContext;
-        const GrClipData* fOldClip;
+        const GrClip* fOldClip;
 
         SkClipStack       fNewClipStack;
-        GrClipData        fNewClipData;
+        GrClip        fNewClipData;
     };
 
     class AutoWideOpenIdentityDraw {
@@ -761,7 +761,7 @@ public:
 
 private:
     GrGpu*                          fGpu;
-    const GrClipData*               fClip;  // TODO: make this ref counted
+    const GrClip*                   fClip;
 
     GrResourceCache*                fResourceCache;
     GrFontCache*                    fFontCache;