Factory methods for heap-allocated SkImageFilter objects.

include/effects/SkDisplacementMapEffect.h

Index: include/effects/SkDisplacementMapEffect.h
diff --git a/include/effects/SkDisplacementMapEffect.h b/include/effects/SkDisplacementMapEffect.h
index 5de4814951a6afb0f299ed90a1db9bf24b8e3e5c..adca30a597cd144acc5572244e3f9b8780da41d9 100644
--- a/include/effects/SkDisplacementMapEffect.h
+++ b/include/effects/SkDisplacementMapEffect.h
@@ -22,14 +22,17 @@ public:
         kKeyBits = 3 // Max value is 4, so 3 bits are required at most

[reed1, 2014/03/04 16:56:42]

I know its not part of this CL, but why is this enum value here, since it is a
dup of kB_ChannelSelectorType?
Does it have to be public?

[Stephen White, 2014/03/04 18:18:00]

It's not a dupe of that value; it's the number of bits required to represent the
enum. I agree that it shouldn't be public; should probably just be in the .cpp.

[Dominik Grewe, 2014/03/07 16:43:38]

I've replaced it with a #define inside the .cpp file.

     };
 
-    SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
-                            ChannelSelectorType yChannelSelector,
-                            SkScalar scale, SkImageFilter* displacement,
-                            SkImageFilter* color = NULL,
-                            const CropRect* cropRect = NULL);
-
     ~SkDisplacementMapEffect();
 
+    static SkDisplacementMapEffect* Create(ChannelSelectorType xChannelSelector,
+                                           ChannelSelectorType yChannelSelector,
+                                           SkScalar scale, SkImageFilter* displacement,
+                                           SkImageFilter* color = NULL,
+                                           const CropRect* cropRect = NULL) {
+        return SkNEW_ARGS(SkDisplacementMapEffect, (xChannelSelector, yChannelSelector, scale,
+                                                    displacement, color, cropRect));
+    }
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
 
     virtual bool onFilterImage(Proxy* proxy,
@@ -52,6 +55,15 @@ protected:
     explicit SkDisplacementMapEffect(SkReadBuffer& buffer);
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
+#ifdef SK_SUPPORT_LEGACY_PUBLICEFFECTCONSTRUCTORS
+public:
+#endif
+    SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
+                            ChannelSelectorType yChannelSelector,
+                            SkScalar scale, SkImageFilter* displacement,
+                            SkImageFilter* color = NULL,
+                            const CropRect* cropRect = NULL);
+
 private:
     ChannelSelectorType fXChannelSelector;
     ChannelSelectorType fYChannelSelector;