Implement InterpolationMedium to filter animated images

Source/platform/graphics/GraphicsContext.cpp

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 1009 matching lines @@
     fillRect(font.selectionRectForText(run, point, h, from, to), backgroundColor);
 }
 
 void GraphicsContext::drawImage(Image* image, const IntPoint& p, CompositeOperator op, RespectImageOrientationEnum shouldRespectImageOrientation)
 {
     if (!image)
         return;
     drawImage(image, FloatRect(IntRect(p, image->size())), FloatRect(FloatPoint(), FloatSize(image->size())), op, shouldRespectImageOrientation);
 }
 
-void GraphicsContext::drawImage(Image* image, const IntRect& r, CompositeOperator op, RespectImageOrientationEnum shouldRespectImageOrientation, bool useLowQualityScale)
+void GraphicsContext::drawImage(Image* image, const IntRect& r, CompositeOperator op, RespectImageOrientationEnum shouldRespectImageOrientation, InterpolationQuality interpolationQuality)
 {
     if (!image)
         return;
-    drawImage(image, FloatRect(r), FloatRect(FloatPoint(), FloatSize(image->size())), op, shouldRespectImageOrientation, useLowQualityScale);
+    drawImage(image, FloatRect(r), FloatRect(FloatPoint(), FloatSize(image->size())), op, shouldRespectImageOrientation, interpolationQuality);
 }
 
-void GraphicsContext::drawImage(Image* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, RespectImageOrientationEnum shouldRespectImageOrientation, bool useLowQualityScale)
+void GraphicsContext::drawImage(Image* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, RespectImageOrientationEnum shouldRespectImageOrientation, InterpolationQuality interpolationQuality)
 {
-    drawImage(image, dest, src, op, blink::WebBlendModeNormal, shouldRespectImageOrientation, useLowQualityScale);
+    drawImage(image, dest, src, op, blink::WebBlendModeNormal, shouldRespectImageOrientation, interpolationQuality);
 }
 
 void GraphicsContext::drawImage(Image* image, const FloatRect& dest)
 {
     if (!image)
         return;
     drawImage(image, dest, FloatRect(IntRect(IntPoint(), image->size())));
 }
 
-void GraphicsContext::drawImage(Image* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, WebBlendMode blendMode, RespectImageOrientationEnum shouldRespectImageOrientation, bool useLowQualityScale)
-{    if (paintingDisabled() || !image)
-        return;
-
-    InterpolationQuality previousInterpolationQuality = InterpolationDefault;
-
-    if (useLowQualityScale) {
-        previousInterpolationQuality = imageInterpolationQuality();
-        setImageInterpolationQuality(InterpolationLow);
-    }
-
-    image->draw(this, dest, src, op, blendMode, shouldRespectImageOrientation);
-
-    if (useLowQualityScale)
-        setImageInterpolationQuality(previousInterpolationQuality);
-}
-
-void GraphicsContext::drawTiledImage(Image* image, const IntRect& destRect, const IntPoint& srcPoint, const IntSize& tileSize, CompositeOperator op, bool useLowQualityScale, WebBlendMode blendMode, const IntSize& repeatSpacing)
+void GraphicsContext::drawImage(Image* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, WebBlendMode blendMode, RespectImageOrientationEnum shouldRespectImageOrientation, InterpolationQuality interpolationQuality)
 {
     if (paintingDisabled() || !image)
         return;
 
-    if (useLowQualityScale) {
+    if (interpolationQuality != InterpolationDefault) {

[Stephen White, 2014/03/18 17:26:43]

Shouldn't this check be against imageInterpolationQuality(), not
InterpolationDefault?

[Alpha Left Google, 2014/03/18 22:59:13]

Done.

         InterpolationQuality previousInterpolationQuality = imageInterpolationQuality();
-        setImageInterpolationQuality(InterpolationLow);
+        setImageInterpolationQuality(interpolationQuality);
+        image->draw(this, dest, src, op, blendMode, shouldRespectImageOrientation);
+        setImageInterpolationQuality(previousInterpolationQuality);
+    } else {
+        image->draw(this, dest, src, op, blendMode, shouldRespectImageOrientation);
+    }
+}
+
+void GraphicsContext::drawTiledImage(Image* image, const IntRect& destRect, const IntPoint& srcPoint, const IntSize& tileSize, CompositeOperator op, InterpolationQuality interpolationQuality, WebBlendMode blendMode, const IntSize& repeatSpacing)
+{
+    if (paintingDisabled() || !image)
+        return;
+
+    if (interpolationQuality != InterpolationDefault) {

[Stephen White, 2014/03/18 17:26:43]

Same here.

[Alpha Left Google, 2014/03/18 22:59:13]

Done.

+        InterpolationQuality previousInterpolationQuality = imageInterpolationQuality();
+        setImageInterpolationQuality(interpolationQuality);
         image->drawTiled(this, destRect, srcPoint, tileSize, op, blendMode, repeatSpacing);
         setImageInterpolationQuality(previousInterpolationQuality);
     } else {
         image->drawTiled(this, destRect, srcPoint, tileSize, op, blendMode, repeatSpacing);
     }
 }
 
 void GraphicsContext::drawTiledImage(Image* image, const IntRect& dest, const IntRect& srcRect,
-    const FloatSize& tileScaleFactor, Image::TileRule hRule, Image::TileRule vRule, CompositeOperator op, bool useLowQualityScale)
+    const FloatSize& tileScaleFactor, Image::TileRule hRule, Image::TileRule vRule, CompositeOperator op, InterpolationQuality interpolationQuality)
 {
     if (paintingDisabled() || !image)
         return;
 
     if (hRule == Image::StretchTile && vRule == Image::StretchTile) {
         // Just do a scale.
         drawImage(image, dest, srcRect, op);
         return;
     }
 
-    if (useLowQualityScale) {
+    if (interpolationQuality != InterpolationDefault) {

[Stephen White, 2014/03/18 17:26:43]

Same here.

[Alpha Left Google, 2014/03/18 22:59:13]

Done.

         InterpolationQuality previousInterpolationQuality = imageInterpolationQuality();
-        setImageInterpolationQuality(InterpolationLow);
+        setImageInterpolationQuality(interpolationQuality);
         image->drawTiled(this, dest, srcRect, tileScaleFactor, hRule, vRule, op);
         setImageInterpolationQuality(previousInterpolationQuality);
     } else {
         image->drawTiled(this, dest, srcRect, tileScaleFactor, hRule, vRule, op);
     }
 }
 
 void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntPoint& p, CompositeOperator op, WebBlendMode blendMode)
 {
     if (!image)
         return;
     drawImageBuffer(image, FloatRect(IntRect(p, image->size())), FloatRect(FloatPoint(), FloatSize(image->size())), op, blendMode);
 }
 
-void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntRect& r, CompositeOperator op, WebBlendMode blendMode, bool useLowQualityScale)
+void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntRect& r, CompositeOperator op, WebBlendMode blendMode, InterpolationQuality interpolationQuality)
 {
     if (!image)
         return;
-    drawImageBuffer(image, FloatRect(r), FloatRect(FloatPoint(), FloatSize(image->size())), op, blendMode, useLowQualityScale);
+    drawImageBuffer(image, FloatRect(r), FloatRect(FloatPoint(), FloatSize(image->size())), op, blendMode, interpolationQuality);
 }
 
 void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntPoint& dest, const IntRect& srcRect, CompositeOperator op, WebBlendMode blendMode)
 {
     drawImageBuffer(image, FloatRect(IntRect(dest, srcRect.size())), FloatRect(srcRect), op, blendMode);
 }
 
-void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntRect& dest, const IntRect& srcRect, CompositeOperator op, WebBlendMode blendMode, bool useLowQualityScale)
+void GraphicsContext::drawImageBuffer(ImageBuffer* image, const IntRect& dest, const IntRect& srcRect, CompositeOperator op, WebBlendMode blendMode, InterpolationQuality interpolationQuality)
 {
-    drawImageBuffer(image, FloatRect(dest), FloatRect(srcRect), op, blendMode, useLowQualityScale);
+    drawImageBuffer(image, FloatRect(dest), FloatRect(srcRect), op, blendMode, interpolationQuality);
 }
 
 void GraphicsContext::drawImageBuffer(ImageBuffer* image, const FloatRect& dest)
 {
     if (!image)
         return;
     drawImageBuffer(image, dest, FloatRect(IntRect(IntPoint(), image->size())));
 }
 
-void GraphicsContext::drawImageBuffer(ImageBuffer* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, WebBlendMode blendMode, bool useLowQualityScale)
+void GraphicsContext::drawImageBuffer(ImageBuffer* image, const FloatRect& dest, const FloatRect& src, CompositeOperator op, WebBlendMode blendMode, InterpolationQuality interpolationQuality)
 {
     if (paintingDisabled() || !image)
         return;
 
-    if (useLowQualityScale) {
+    if (interpolationQuality != InterpolationDefault) {

[Stephen White, 2014/03/18 17:26:43]

Same here. (Tangentially, I wonder if these functions could be templated and/or
refactored.)

[Alpha Left Google, 2014/03/18 22:59:13]

Done. Yeah I'll leave that refactoring as a separate change.

         InterpolationQuality previousInterpolationQuality = imageInterpolationQuality();
-        setImageInterpolationQuality(InterpolationLow);
-        image->draw(this, dest, src, op, blendMode, useLowQualityScale);
+        setImageInterpolationQuality(interpolationQuality);
+        image->draw(this, dest, src, op, blendMode, interpolationQuality);

[Stephen White, 2014/03/18 17:26:43]

(Not new to this patch, but it seems odd that we have to both set the
interpolation quality, and pass it to image->draw() as well.)

[Alpha Left Google, 2014/03/18 22:59:13]

Indeed. :(

         setImageInterpolationQuality(previousInterpolationQuality);
     } else {
-        image->draw(this, dest, src, op, blendMode, useLowQualityScale);
+        image->draw(this, dest, src, op, blendMode, interpolationQuality);
     }
 }
 
 void GraphicsContext::writePixels(const SkImageInfo& info, const void* pixels, size_t rowBytes, int x, int y)
 {
     if (paintingDisabled())
         return;
 
     m_canvas->writePixels(info, pixels, rowBytes, x, y);
 
@@ skipping 759 matching lines @@
 
 void GraphicsContext::didDrawTextInRect(const SkRect& textRect)
 {
     if (m_trackTextRegion) {
         TRACE_EVENT0("skia", "PlatformContextSkia::trackTextRegion");
         m_textRegion.join(textRect);
     }
 }
 
 }