Refactor drawContext/RenderTarget creation

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"
@@ skipping 77 matching lines @@
     : INHERITED(&input, 1, cropRect)
     , fRegion(region)
     , fInnerThreshold(innerThreshold)
     , fOuterThreshold(outerThreshold) {
 }
 
 #if SK_SUPPORT_GPU
 sk_sp<GrTexture> SkAlphaThresholdFilterImpl::createMaskTexture(GrContext* context,
                                                                const SkMatrix& inMatrix,
                                                                const SkIRect& bounds) const {
-    GrSurfaceDesc maskDesc;
+    GrPixelConfig config;
     if (context->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
-        maskDesc.fConfig = kAlpha_8_GrPixelConfig;
+        config = kAlpha_8_GrPixelConfig;
     } else {
-        maskDesc.fConfig = kRGBA_8888_GrPixelConfig;
-    }
-    maskDesc.fFlags = kRenderTarget_GrSurfaceFlag;
-    // Add one pixel of border to ensure that clamp mode will be all zeros
-    // the outside.
-    maskDesc.fWidth = bounds.width();
-    maskDesc.fHeight = bounds.height();
-    sk_sp<GrTexture> maskTexture(context->textureProvider()->createApproxTexture(maskDesc));
-    if (!maskTexture) {
-        return nullptr;
+        config = kRGBA_8888_GrPixelConfig;
     }
 
-    sk_sp<GrDrawContext> drawContext(
-                                context->drawContext(sk_ref_sp(maskTexture->asRenderTarget())));
+    sk_sp<GrDrawContext> drawContext(context->newDrawContext(GrContext::kLoose_BackingFit,
+                                                             bounds.width(), bounds.height(),
+                                                             config));
     if (!drawContext) {
         return nullptr;
     }
 
     GrPaint grPaint;
     grPaint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
     SkRegion::Iterator iter(fRegion);
     drawContext->clear(nullptr, 0x0, true);
 
     GrClip clip(SkRect::Make(SkIRect::MakeWH(bounds.width(), bounds.height())));
     while (!iter.done()) {
         SkRect rect = SkRect::Make(iter.rect());
         drawContext->drawRect(clip, grPaint, inMatrix, rect);
         iter.next();
     }
 
-    return maskTexture;
+    return drawContext->asTexture();
 }
 #endif
 
 void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fInnerThreshold);
     buffer.writeScalar(fOuterThreshold);
     buffer.writeRegion(fRegion);
 }
 
@@ skipping 124 matching lines @@
                                           dst);
 }
 
 #ifndef SK_IGNORE_TO_STRING
 void SkAlphaThresholdFilterImpl::toString(SkString* str) const {
     str->appendf("SkAlphaThresholdImageFilter: (");
     str->appendf("inner: %f outer: %f", fInnerThreshold, fOuterThreshold);
     str->append(")");
 }
 #endif