1 files changed, 85 insertions, 17 deletions

diff --git a/WebCore/rendering/SVGImageBufferTools.cpp b/WebCore/rendering/SVGImageBufferTools.cpp
index 5b45ccc..709bf10 100644
--- a/WebCore/rendering/SVGImageBufferTools.cpp
+++ b/WebCore/rendering/SVGImageBufferTools.cpp
@@ -22,50 +22,118 @@
 #if ENABLE(SVG)
 #include "SVGImageBufferTools.h"
 
+#include "FrameView.h"
 #include "GraphicsContext.h"
 #include "RenderObject.h"
+#include "RenderSVGContainer.h"
+#include "RenderSVGRoot.h"
 
 namespace WebCore {
 
-AffineTransform SVGImageBufferTools::absoluteTransformFromContext(GraphicsContext* context)
+static AffineTransform& currentContentTransformation()
 {
-    // Extract current transformation matrix used in the original context. Note that this coordinate
-    // system is flipped compared to SVGs internal coordinate system, done in WebKit level. Fix
-    // this transformation by flipping the y component.
-    return context->getCTM() * AffineTransform().flipY();
+    DEFINE_STATIC_LOCAL(AffineTransform, s_currentContentTransformation, ());
+    return s_currentContentTransformation;
 }
 
-bool SVGImageBufferTools::createImageBuffer(const AffineTransform& absoluteTransform, const FloatRect& absoluteTargetRect, OwnPtr<ImageBuffer>& imageBuffer, ImageColorSpace colorSpace)
+void SVGImageBufferTools::calculateTransformationToOutermostSVGCoordinateSystem(const RenderObject* renderer, AffineTransform& absoluteTransform)
 {
-    IntRect imageRect = enclosingIntRect(absoluteTargetRect);
-    if (imageRect.isEmpty())
+    const RenderObject* current = renderer;
+    ASSERT(current);
+
+    absoluteTransform = currentContentTransformation();
+    while (current) {
+        absoluteTransform.multiply(current->localToParentTransform());
+        if (current->isSVGRoot())
+            break;
+        current = current->parent();
+    }
+}
+
+bool SVGImageBufferTools::createImageBuffer(const FloatRect& absoluteTargetRect, const FloatRect& clampedAbsoluteTargetRect, OwnPtr<ImageBuffer>& imageBuffer, ImageColorSpace colorSpace)
+{
+    IntSize imageSize(roundedImageBufferSize(clampedAbsoluteTargetRect.size()));
+    IntSize unclampedImageSize(SVGImageBufferTools::roundedImageBufferSize(absoluteTargetRect.size()));
+
+    // Don't create empty ImageBuffers.
+    if (imageSize.isEmpty())
         return false;
 
-    // Allocate an image buffer as big as the absolute unclipped size of the object
-    OwnPtr<ImageBuffer> image = ImageBuffer::create(imageRect.size(), colorSpace);
+    OwnPtr<ImageBuffer> image = ImageBuffer::create(imageSize, colorSpace);
     if (!image)
         return false;
 
     GraphicsContext* imageContext = image->context();
+    ASSERT(imageContext);
 
-    // Transform the mask image coordinate system to absolute screen coordinates
-    imageContext->translate(-absoluteTargetRect.x(), -absoluteTargetRect.y());
-    imageContext->concatCTM(absoluteTransform);
+    // Compensate rounding effects, as the absolute target rect is using floating-point numbers and the image buffer size is integer.
+    imageContext->scale(FloatSize(unclampedImageSize.width() / absoluteTargetRect.width(), unclampedImageSize.height() / absoluteTargetRect.height()));
 
     imageBuffer = image.release();
     return true;
 }
 
-void SVGImageBufferTools::clipToImageBuffer(GraphicsContext* context, const AffineTransform& absoluteTransform, const FloatRect& absoluteTargetRect, ImageBuffer* imageBuffer)
+void SVGImageBufferTools::renderSubtreeToImageBuffer(ImageBuffer* image, RenderObject* item, const AffineTransform& subtreeContentTransformation)
+{
+    ASSERT(item);
+    ASSERT(image);
+    ASSERT(image->context());
+
+    PaintInfo info(image->context(), PaintInfo::infiniteRect(), PaintPhaseForeground, 0, 0, 0);
+
+    // FIXME: isSVGContainer returns true for RenderSVGViewportContainer, so if this is ever
+    // called with one of those, we will read from the wrong offset in an object due to a bad cast.
+    RenderSVGContainer* svgContainer = 0;
+    if (item && item->isSVGContainer())
+        svgContainer = toRenderSVGContainer(item);
+
+    bool drawsContents = svgContainer ? svgContainer->drawsContents() : false;
+    if (svgContainer && !drawsContents)
+        svgContainer->setDrawsContents(true);
+
+    AffineTransform& contentTransformation = currentContentTransformation();
+    AffineTransform savedContentTransformation = contentTransformation;
+    contentTransformation.multiply(subtreeContentTransformation);
+
+    item->layoutIfNeeded();
+    item->paint(info, 0, 0);
+
+    contentTransformation = savedContentTransformation;
+
+    if (svgContainer && !drawsContents)
+        svgContainer->setDrawsContents(false);
+}
+
+void SVGImageBufferTools::clipToImageBuffer(GraphicsContext* context, const AffineTransform& absoluteTransform, const FloatRect& clampedAbsoluteTargetRect, OwnPtr<ImageBuffer>& imageBuffer)
 {
     ASSERT(context);
     ASSERT(imageBuffer);
 
-    // The mask image has been created in the device coordinate space, as the image should not be scaled.
-    // So the actual masking process has to be done in the device coordinate space as well.
+    // The mask image has been created in the absolute coordinate space, as the image should not be scaled.
+    // So the actual masking process has to be done in the absolute coordinate space as well.
     context->concatCTM(absoluteTransform.inverse());
-    context->clipToImageBuffer(imageBuffer, absoluteTargetRect);
+    context->clipToImageBuffer(imageBuffer.get(), clampedAbsoluteTargetRect);
     context->concatCTM(absoluteTransform);
+
+    // When nesting resources, with objectBoundingBox as content unit types, there's no use in caching the
+    // resulting image buffer as the parent resource already caches the result.
+    if (!currentContentTransformation().isIdentity())
+        imageBuffer.clear();
+}
+
+IntSize SVGImageBufferTools::roundedImageBufferSize(const FloatSize& size)
+{
+    return IntSize(static_cast<int>(lroundf(size.width())), static_cast<int>(lroundf(size.height())));
+}
+
+FloatRect SVGImageBufferTools::clampedAbsoluteTargetRectForRenderer(const RenderObject* renderer, const FloatRect& absoluteTargetRect)
+{
+    ASSERT(renderer);
+
+    const RenderSVGRoot* svgRoot = SVGRenderSupport::findTreeRootObject(renderer);
+    FloatRect clampedAbsoluteTargetRect = absoluteTargetRect;
+    clampedAbsoluteTargetRect.intersect(svgRoot->contentBoxRect());
+    return clampedAbsoluteTargetRect;
 }
 
 }