change signature for virtual related to saveLayer, passing SaveLayerRec

include/core/SkCanvas.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCanvas_DEFINED
 #define SkCanvas_DEFINED
 
@@ skipping 373 matching lines @@
                       limit the size of the offscreen, and thus drawing may be
                       clipped to it, though that clipping is not guaranteed to
                       happen. If exact clipping is desired, use clipRect().
         @param alpha  This is applied to the offscreen when restore() is called.
         @param flags  LayerFlags
         @return The value to pass to restoreToCount() to balance this save()
     */
     SK_ATTR_EXTERNALLY_DEPRECATED("SaveFlags use is deprecated")
     int saveLayerAlpha(const SkRect* bounds, U8CPU alpha, SaveFlags flags);
 
+    enum {
+        kIsOpaque_SaveLayerFlag         = 1 << 0,
+        kPreserveLCDText_SaveLayerFlag  = 1 << 1,
+    };
+    typedef uint32_t SaveLayerFlags;
+
+    struct SaveLayerRec {
+        SaveLayerRec() : fBounds(nullptr), fPaint(nullptr), fSaveLayerFlags(0) {}
+        SaveLayerRec(const SkRect* bounds, const SkPaint* paint, SaveLayerFlags saveLayerFlags = 0)
+            : fBounds(bounds)
+            , fPaint(paint)
+            , fSaveLayerFlags(saveLayerFlags)
+        {}
+
+        const SkRect*   fBounds;    // optional
+        const SkPaint*  fPaint;     // optional
+        SaveLayerFlags  fSaveLayerFlags;
+    };
+
+    int saveLayer(const SaveLayerRec&);
+
     /** This call balances a previous call to save(), and is used to remove all
         modifications to the matrix/clip/drawFilter state since the last save
         call.
         It is an error to call restore() more times than save() was called.
     */
     void restore();
 
     /** Returns the number of matrix/clip states on the SkCanvas' private stack.
         This will equal # save() calls - # restore() calls + 1. The save count on
         a new canvas is 1.
@@ skipping 809 matching lines @@
 
     // default impl defers to its device
     virtual bool onPeekPixels(SkPixmap*);
     virtual bool onAccessTopLayerPixels(SkPixmap*);
 
     // Subclass save/restore notifiers.
     // Overriders should call the corresponding INHERITED method up the inheritance chain.
     // willSaveLayer()'s return value may suppress full layer allocation.
     enum SaveLayerStrategy {
         kFullLayer_SaveLayerStrategy,
-        kNoLayer_SaveLayerStrategy
+        kNoLayer_SaveLayerStrategy,
     };
 
     virtual void willSave() {}
+#ifdef SK_SUPPORT_LEGACY_SAVELAYERPARAMS
     virtual SaveLayerStrategy willSaveLayer(const SkRect*, const SkPaint*, SaveFlags) {
         return kFullLayer_SaveLayerStrategy;
     }
+    virtual SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec&);
+#else
+    virtual SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec&) {

[f(malita), 2015/12/17 22:23:28]

While reviewing the Chromium side of this CL, it occurred to me that
"getSaveLayerStrategy" is somewhat misleading: it sounds like a plain getter,
which may suggest one doesn't necessarily have to call the inherited version. 
But it acts more like a notifier, with some ancestor classes performing related
work and relying on receiving this notification.

I can't think of a better name, but maybe we should document that overriders are
required to call up the inheritance chain.

[reed1, 2015/12/17 22:29:39]

That is documented on the strategy enum, but I will push it down to this method.

+        return kFullLayer_SaveLayerStrategy;
+    }
+#endif
     virtual void willRestore() {}
     virtual void didRestore() {}
     virtual void didConcat(const SkMatrix&) {}
     virtual void didSetMatrix(const SkMatrix&) {}
 
     virtual void onDrawDRRect(const SkRRect&, const SkRRect&, const SkPaint&);
 
     virtual void onDrawText(const void* text, size_t byteLength, SkScalar x,
                             SkScalar y, const SkPaint& paint);
 
@@ skipping 57 matching lines @@
     // Returns the canvas to be used by DrawIter. Default implementation
     // returns this. Subclasses that encapsulate an indirect canvas may
     // need to overload this method. The impl must keep track of this, as it
     // is not released or deleted by the caller.
     virtual SkCanvas* canvasForDrawIter();
 
     // Clip rectangle bounds. Called internally by saveLayer.
     // returns false if the entire rectangle is entirely clipped out
     // If non-NULL, The imageFilter parameter will be used to expand the clip
     // and offscreen bounds for any margin required by the filter DAG.
-    bool clipRectBounds(const SkRect* bounds, SaveFlags flags,
-                        SkIRect* intersection,
+    bool clipRectBounds(const SkRect* bounds, SaveLayerFlags, SkIRect* intersection,
                         const SkImageFilter* imageFilter = NULL);
 
 private:
-    enum PrivateSaveFlags {
-        // These must not overlap the public flags.
-        kPreserveLCDText_PrivateSaveFlag = 1 << 5,
+    enum PrivateSaveLayerFlags {
+        kDontClipToLayer_PrivateSaveLayerFlag   = 1 << 31,
     };
 
+    static bool BoundsAffectsClip(SaveLayerFlags);
+    static uint32_t SaveFlagsToSaveLayerFlags(SaveFlags);
+
     enum ShaderOverrideOpacity {
         kNone_ShaderOverrideOpacity,        //!< there is no overriding shader (bitmap or image)
         kOpaque_ShaderOverrideOpacity,      //!< the overriding shader is opaque
         kNotOpaque_ShaderOverrideOpacity,   //!< the overriding shader may not be opaque
     };
 
     // notify our surface (if we have one) that we are about to draw, so it
     // can perform copy-on-write or invalidate any cached images
     void predrawNotify(bool willOverwritesEntireSurface = false);
     void predrawNotify(const SkRect* rect, const SkPaint* paint, ShaderOverrideOpacity);
@@ skipping 39 matching lines @@
 
     friend class SkDrawIter;        // needs setupDrawForLayerDevice()
     friend class AutoDrawLooper;
     friend class SkLua;             // needs top layer size and offset
     friend class SkDebugCanvas;     // needs experimental fAllowSimplifyClip
     friend class SkSurface_Raster;  // needs getDevice()
     friend class SkRecorder;        // InitFlags
     friend class SkNoSaveLayerCanvas;   // InitFlags
     friend class SkPictureImageFilter;  // SkCanvas(SkBaseDevice*, SkSurfaceProps*, InitFlags)
     friend class SkPictureRecord;   // predrawNotify (why does it need it? <reed>)
+    friend class SkPicturePlayback; // SaveFlagsToSaveLayerFlags
 
     enum InitFlags {
         kDefault_InitFlags                  = 0,
         kConservativeRasterClip_InitFlag    = 1 << 0,
     };
     SkCanvas(const SkIRect& bounds, InitFlags);
     SkCanvas(SkBaseDevice* device, InitFlags);
 
     void resetForNextPicture(const SkIRect& bounds);
 
@@ skipping 11 matching lines @@
      * Gets the size/origin of the top level layer in global canvas coordinates. We don't want this
      * to be public because it exposes decisions about layer sizes that are internal to the canvas.
      */
     SkISize getTopLayerSize() const;
     SkIPoint getTopLayerOrigin() const;
 
     void internalDrawBitmapRect(const SkBitmap& bitmap, const SkRect* src,
                                 const SkRect& dst, const SkPaint* paint,
                                 SrcRectConstraint);
     void internalDrawPaint(const SkPaint& paint);
-    void internalSaveLayer(const SkRect* bounds, const SkPaint*, SaveFlags, SaveLayerStrategy);
+    void internalSaveLayer(const SaveLayerRec&, SaveLayerStrategy);
     void internalDrawDevice(SkBaseDevice*, int x, int y, const SkPaint*, bool isBitmapDevice);
 
     // shared by save() and saveLayer()
     void internalSave();
     void internalRestore();
     static void DrawRect(const SkDraw& draw, const SkPaint& paint,
                          const SkRect& r, SkScalar textSize);
     static void DrawTextDecorations(const SkDraw& draw, const SkPaint& paint,
                                     const char text[], size_t byteLength,
                                     SkScalar x, SkScalar y);
@@ skipping 145 matching lines @@
 
 class SkCanvasClipVisitor {
 public:
     virtual ~SkCanvasClipVisitor();
     virtual void clipRect(const SkRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipRRect(const SkRRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipPath(const SkPath&, SkRegion::Op, bool antialias) = 0;
 };
 
 #endif