Add scale param to SkAlphaThresholdFilter.

src/effects/SkAlphaThresholdFilter.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAlphaThresholdFilter.h"
 #include "SkBitmap.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkRegion.h"
 
 class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter {
 public:
-    SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold, SkScalar outerThreshold);
+    SkAlphaThresholdFilterImpl(const SkRegion& region, const SkMatrix& scale,
+                               SkScalar innerThreshold, SkScalar outerThreshold);
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
 
 protected:
     explicit SkAlphaThresholdFilterImpl(SkReadBuffer& buffer);
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
                                SkBitmap* result, SkIPoint* offset) const SK_OVERRIDE;
 #if SK_SUPPORT_GPU
     virtual bool asNewEffect(GrEffectRef** effect, GrTexture* texture,
                              const SkMatrix& matrix, const SkIRect& bounds) const SK_OVERRIDE;
 #endif
 
 private:
     SkRegion fRegion;
+    SkMatrix fScale;
     SkScalar fInnerThreshold;
     SkScalar fOuterThreshold;
     typedef SkImageFilter INHERITED;
 };
 
 SkImageFilter* SkAlphaThresholdFilter::Create(const SkRegion& region,
                                               SkScalar innerThreshold,
                                               SkScalar outerThreshold) {
-    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, innerThreshold, outerThreshold));
+    SkMatrix scale;
+    scale.setScale(1.f, 1.f);

[bsalomon, 2014/07/11 13:00:25]

SkMatrix has a reset() function that will set it to identity. I think that's
clearer than calling scale(1,1).

[garykac, 2014/07/11 19:10:59]

Done.

+    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, scale, innerThreshold, outerThreshold));
+}
+
+SkImageFilter* SkAlphaThresholdFilter::Create(const SkRegion& region,
+                                              const SkMatrix& scale,
+                                              SkScalar innerThreshold,
+                                              SkScalar outerThreshold) {
+    return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, scale, innerThreshold, outerThreshold));
 }
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrCoordTransform.h"
 #include "GrEffect.h"
 #include "gl/GrGLEffect.h"
 #include "GrTBackendEffectFactory.h"
 #include "GrTextureAccess.h"
 
@@ skipping 174 matching lines @@
         *validFlags = kA_GrColorComponentFlag;
     } else {
         *validFlags = 0;
     }
 }
 
 #endif
 
 SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(SkReadBuffer& buffer)
   : INHERITED(1, buffer) {
+    buffer.readMatrix(&fScale);
     fInnerThreshold = buffer.readScalar();
     fOuterThreshold = buffer.readScalar();
     buffer.readRegion(&fRegion);
 }
 
 SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(const SkRegion& region,
+                                                       const SkMatrix& scale,
                                                        SkScalar innerThreshold,
                                                        SkScalar outerThreshold)
     : INHERITED(0)
     , fRegion(region)
+    , fScale(scale)
     , fInnerThreshold(innerThreshold)
     , fOuterThreshold(outerThreshold) {
 }
 
 #if SK_SUPPORT_GPU
 bool SkAlphaThresholdFilterImpl::asNewEffect(GrEffectRef** effect, GrTexture* texture,
                                              const SkMatrix& in_matrix, const SkIRect&) const {
     if (effect) {
         GrContext* context = texture->getContext();
         GrTextureDesc maskDesc;
@@ skipping 15 matching lines @@
 
         {
             GrContext::AutoRenderTarget art(context, ast.texture()->asRenderTarget());
             GrPaint grPaint;
             grPaint.setBlendFunc(kOne_GrBlendCoeff, kZero_GrBlendCoeff);
             SkRegion::Iterator iter(fRegion);
             context->clear(NULL, 0x0, true);
 
             SkMatrix old_matrix = context->getMatrix();
             context->setMatrix(in_matrix);
+            context->concatMatrix(fScale);
 
             while (!iter.done()) {
                 SkRect rect = SkRect::Make(iter.rect());
                 context->drawRect(grPaint, rect);
                 iter.next();
             }
             context->setMatrix(old_matrix);
         }
 
         *effect = AlphaThresholdEffect::Create(texture,
                                                maskTexture,
                                                fInnerThreshold,
                                                fOuterThreshold);
     }
     return true;
 }
 #endif
 
 void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
+    buffer.writeMatrix(fScale);
     buffer.writeScalar(fInnerThreshold);
     buffer.writeScalar(fOuterThreshold);
     buffer.writeRegion(fRegion);
 }
 
 bool SkAlphaThresholdFilterImpl::onFilterImage(Proxy*, const SkBitmap& src,
                                                const Context& ctx, SkBitmap* dst,
                                                SkIPoint* offset) const {
     SkASSERT(src.colorType() == kN32_SkColorType);
 
@@ skipping 46 matching lines @@
                                                   (U8CPU)(SkColorGetG(source) * scale),
                                                   (U8CPU)(SkColorGetB(source) * scale));
                 }
             }
             dptr[y * dst->width() + x] = output_color;
         }
     }
 
     return true;
 }