Add scale param to SkAlphaThresholdFilter.

src/effects/SkAlphaThresholdFilter.cpp

Index: src/effects/SkAlphaThresholdFilter.cpp
diff --git a/src/effects/SkAlphaThresholdFilter.cpp b/src/effects/SkAlphaThresholdFilter.cpp
index 6fcd2b4351e238b51ffc5588f58ad79a5c38c163..af3887359a4e6173e1dc69d4a556fc8599ba0eaa 100644
--- a/src/effects/SkAlphaThresholdFilter.cpp
+++ b/src/effects/SkAlphaThresholdFilter.cpp
@@ -13,7 +13,8 @@
 
 class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter {
 public:
-    SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold, SkScalar outerThreshold);
+    SkAlphaThresholdFilterImpl(const SkRegion& region, const SkMatrix& transform,
+                               SkScalar innerThreshold, SkScalar outerThreshold);
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
 
@@ -30,6 +31,7 @@ protected:
 
 private:
     SkRegion fRegion;
+    SkMatrix fTransform;
     SkScalar fInnerThreshold;
     SkScalar fOuterThreshold;
     typedef SkImageFilter INHERITED;
@@ -38,7 +40,16 @@ private:
 SkImageFilter* SkAlphaThresholdFilter::Create(const SkRegion& region,
                                               SkScalar innerThreshold,
                                               SkScalar outerThreshold) {
-    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, innerThreshold, outerThreshold));
+    SkMatrix transform;
+    transform.reset();
+    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, transform, innerThreshold, outerThreshold));
+}
+
+SkImageFilter* SkAlphaThresholdFilter::Create(const SkRegion& region,
+                                              const SkMatrix& transform,

[Stephen White, 2014/07/11 20:15:24]

Is there a reason this needs to be a separate matrix, and can't be part of the
CTM? Most filters already transform their parameters by the CTM at draw time.

+                                              SkScalar innerThreshold,
+                                              SkScalar outerThreshold) {
+    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, transform, innerThreshold, outerThreshold));
 }
 
 #if SK_SUPPORT_GPU
@@ -233,16 +244,19 @@ void AlphaThresholdEffect::getConstantColorComponents(GrColor* color, uint32_t*
 
 SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(SkReadBuffer& buffer)
   : INHERITED(1, buffer) {
+    buffer.readMatrix(&fTransform);
     fInnerThreshold = buffer.readScalar();
     fOuterThreshold = buffer.readScalar();
     buffer.readRegion(&fRegion);
 }
 
 SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(const SkRegion& region,
+                                                       const SkMatrix& transform,
                                                        SkScalar innerThreshold,
                                                        SkScalar outerThreshold)
     : INHERITED(0)
     , fRegion(region)
+    , fTransform(transform)
     , fInnerThreshold(innerThreshold)
     , fOuterThreshold(outerThreshold) {
 }
@@ -278,6 +292,7 @@ bool SkAlphaThresholdFilterImpl::asNewEffect(GrEffectRef** effect, GrTexture* te
 
             SkMatrix old_matrix = context->getMatrix();
             context->setMatrix(in_matrix);
+            context->concatMatrix(fTransform);
 
             while (!iter.done()) {
                 SkRect rect = SkRect::Make(iter.rect());
@@ -298,6 +313,7 @@ bool SkAlphaThresholdFilterImpl::asNewEffect(GrEffectRef** effect, GrTexture* te
 
 void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
+    buffer.writeMatrix(fTransform);
     buffer.writeScalar(fInnerThreshold);
     buffer.writeScalar(fOuterThreshold);
     buffer.writeRegion(fRegion);