[SVG] Remove calculateDeviceSpaceTransformation()

Source/core/rendering/svg/SVGRenderingContext.cpp

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 177 matching lines @@
     contentTransformation = subtreeContentTransformation * contentTransformation;
 }
 
 SubtreeContentTransformScope::~SubtreeContentTransformScope()
 {
     currentContentTransformation() = m_savedContentTransformation;
 }
 
 float SVGRenderingContext::calculateScreenFontSizeScalingFactor(const RenderObject* renderer)
 {
-    ASSERT(renderer);
-
-    AffineTransform ctm;
-    // FIXME: calculateDeviceSpaceTransformation() queries layer compositing state - which is not
-    // supported during layout. Hence, the result may not include all CSS transforms.
-    calculateDeviceSpaceTransformation(renderer, ctm);
-    return narrowPrecisionToFloat(sqrt((pow(ctm.xScale(), 2) + pow(ctm.yScale(), 2)) / 2));
-}
-
-void SVGRenderingContext::calculateDeviceSpaceTransformation(const RenderObject* renderer, AffineTransform& absoluteTransform)
-{
     // FIXME: trying to compute a device space transform at record time is wrong. All clients
     // should be updated to avoid relying on this information, and the method should be removed.
 
     ASSERT(renderer);
     // We're about to possibly clear renderer, so save the deviceScaleFactor now.
     float deviceScaleFactor = renderer->document().frameHost()->deviceScaleFactor();
 
     // Walk up the render tree, accumulating SVG transforms.
-    absoluteTransform = currentContentTransformation();
+    AffineTransform ctm = currentContentTransformation();
     while (renderer) {
-        absoluteTransform = renderer->localToParentTransform() * absoluteTransform;
+        ctm = renderer->localToParentTransform() * ctm;
         if (renderer->isSVGRoot())
             break;
         renderer = renderer->parent();
     }
 
     // Continue walking up the layer tree, accumulating CSS transforms.
+    // FIXME: this queries layer compositing state - which is not
+    // supported during layout. Hence, the result may not include all CSS transforms.
     RenderLayer* layer = renderer ? renderer->enclosingLayer() : 0;
     while (layer && layer->isAllowedToQueryCompositingState()) {
         // We can stop at compositing layers, to match the backing resolution.
         // FIXME: should we be computing the transform to the nearest composited layer,
         // or the nearest composited layer that does not paint into its ancestor?
         // I think this is the nearest composited ancestor since we will inherit its
         // transforms in the composited layer tree.
         if (layer->compositingState() != NotComposited)
             break;
 
         if (TransformationMatrix* layerTransform = layer->transform())
-            absoluteTransform = layerTransform->toAffineTransform() * absoluteTransform;
+            ctm = layerTransform->toAffineTransform() * ctm;
 
         layer = layer->parent();
     }
 
-    absoluteTransform.scale(deviceScaleFactor);
+    ctm.scale(deviceScaleFactor);
+
+    return narrowPrecisionToFloat(sqrt((pow(ctm.xScale(), 2) + pow(ctm.yScale(), 2)) / 2));
 }
 
 void SVGRenderingContext::renderSubtree(GraphicsContext* context, RenderObject* item)
 {
     ASSERT(context);
     ASSERT(item);
     ASSERT(!item->needsLayout());
 
     PaintInfo info(context, PaintInfo::infiniteRect(), PaintPhaseForeground, PaintBehaviorNormal);
     item->paint(info, IntPoint());
@@ skipping 24 matching lines @@
             SVGImagePainter::paintForeground(toRenderSVGImage(*m_object), bufferedInfo);
         } else
             return false;
     }
 
     m_paintInfo->context->drawImageBuffer(imageBuffer.get(), boundingBox);
     return true;
 }
 
 } // namespace blink