Factory methods for heap-allocated SkPathEffect and SkXfermode objects.

This is part of an effort to ensure that all SkPaint effects can only be
allocated on the heap.

This patch makes the constructors of SkPathEffect, SkXfermode and
their subclasses non-public and instead provides factory methods for
creating these objects on the heap. We temporarily keep the constructors
of the following classes public to not break Chrome/Blink:

SkXfermode
SkCornerPathEffect
SkDashPathEffect

BUG=skia:2187
R=scroggo@google.com, reed@google.com, mtklein@google.com, bungeman@google.com

Author: dominikg@chromium.org

Review URL: https://codereview.chromium.org/166583002

git-svn-id: http://skia.googlecode.com/svn/trunk@13519 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 20 insertions, 7 deletions

diff --git a/include/core/SkPathEffect.h b/include/core/SkPathEffect.h
index 3f38f3a101..86ccf86a92 100644
--- a/include/core/SkPathEffect.h
+++ b/include/core/SkPathEffect.h
@@ -31,8 +31,6 @@ class SK_API SkPathEffect : public SkFlattenable {
 public:
     SK_DECLARE_INST_COUNT(SkPathEffect)
 
-    SkPathEffect() {}
-
     /**
      *  Given a src path (input) and a stroke-rec (input and output), apply
      *  this effect to the src path, returning the new path in dst, and return
@@ -109,6 +107,7 @@ public:
     SK_DEFINE_FLATTENABLE_TYPE(SkPathEffect)
 
 protected:
+    SkPathEffect() {}
     SkPathEffect(SkReadBuffer& buffer) : INHERITED(buffer) {}
 
 private:
@@ -127,10 +126,10 @@ private:
 */
 class SkPairPathEffect : public SkPathEffect {
 public:
-    SkPairPathEffect(SkPathEffect* pe0, SkPathEffect* pe1);
     virtual ~SkPairPathEffect();
 
 protected:
+    SkPairPathEffect(SkPathEffect* pe0, SkPathEffect* pe1);
     SkPairPathEffect(SkReadBuffer&);
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
@@ -153,8 +152,9 @@ public:
         The reference counts for outer and inner are both incremented in the constructor,
         and decremented in the destructor.
     */
-    SkComposePathEffect(SkPathEffect* outer, SkPathEffect* inner)
-        : INHERITED(outer, inner) {}
+    static SkComposePathEffect* Create(SkPathEffect* outer, SkPathEffect* inner) {
+        return SkNEW_ARGS(SkComposePathEffect, (outer, inner));
+    }
 
     virtual bool filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec*, const SkRect*) const SK_OVERRIDE;
@@ -164,6 +164,12 @@ public:
 protected:
     SkComposePathEffect(SkReadBuffer& buffer) : INHERITED(buffer) {}
 
+#ifdef SK_SUPPORT_LEGACY_PUBLICEFFECTCONSTRUCTORS
+public:
+#endif
+    SkComposePathEffect(SkPathEffect* outer, SkPathEffect* inner)
+        : INHERITED(outer, inner) {}
+
 private:
     // illegal
     SkComposePathEffect(const SkComposePathEffect&);
@@ -184,8 +190,9 @@ public:
         The reference counts for first and second are both incremented in the constructor,
         and decremented in the destructor.
     */
-    SkSumPathEffect(SkPathEffect* first, SkPathEffect* second)
-        : INHERITED(first, second) {}
+    static SkSumPathEffect* Create(SkPathEffect* first, SkPathEffect* second) {
+        return SkNEW_ARGS(SkSumPathEffect, (first, second));
+    }
 
     virtual bool filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec*, const SkRect*) const SK_OVERRIDE;
@@ -195,6 +202,12 @@ public:
 protected:
     SkSumPathEffect(SkReadBuffer& buffer) : INHERITED(buffer) {}
 
+#ifdef SK_SUPPORT_LEGACY_PUBLICEFFECTCONSTRUCTORS
+public:
+#endif
+    SkSumPathEffect(SkPathEffect* first, SkPathEffect* second)
+        : INHERITED(first, second) {}
+
 private:
     // illegal
     SkSumPathEffect(const SkSumPathEffect&);