SVGResource* SVGClipPathElement::canvasResource()
{
if (!m_clipper)
m_clipper = SVGResourceClipper::create();
else
m_clipper->resetClipData();
bool bbox = clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX;
RenderStyle* clipPathStyle = styleForRenderer(parent()->renderer()); // FIXME: Manual style resolution is a hack
for (Node* n = firstChild(); n; n = n->nextSibling()) {
if (n->isSVGElement() && static_cast<SVGElement*>(n)->isStyledTransformable()) {
SVGStyledTransformableElement* styled = static_cast<SVGStyledTransformableElement*>(n);
RenderStyle* pathStyle = document()->styleSelector()->styleForElement(styled, clipPathStyle);
if (pathStyle->display() != NONE) {
Path pathData = styled->toClipPath();
// FIXME: How do we know the element has done a layout?
pathData.transform(styled->animatedLocalTransform());
if (!pathData.isEmpty())
m_clipper->addClipData(pathData, pathStyle->svgStyle()->clipRule(), bbox);
}
pathStyle->deref(document()->renderArena());
}
}
if (m_clipper->clipData().isEmpty()) {
Path pathData;
pathData.addRect(FloatRect());
m_clipper->addClipData(pathData, RULE_EVENODD, bbox);
}
clipPathStyle->deref(document()->renderArena());
return m_clipper.get();
}
FloatRect RenderSVGResourceClipper::resourceBoundingBox(const FloatRect& objectBoundingBox) const
{
FloatRect clipRect;
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
if (!childNode->isSVGElement() || !static_cast<SVGElement*>(childNode)->isStyledTransformable())
continue;
SVGStyledTransformableElement* styled = static_cast<SVGStyledTransformableElement*>(childNode);
RenderStyle* style = styled->renderer() ? styled->renderer()->style() : 0;
if (!style || style->display() == NONE || styled->toClipPath().isEmpty())
continue;
clipRect.unite(styled->renderer()->objectBoundingBox());
}
if (clipRect.isEmpty())
return FloatRect();
if (static_cast<SVGClipPathElement*>(node())->clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
AffineTransform obbTransform;
obbTransform.translate(objectBoundingBox.x(), objectBoundingBox.y());
obbTransform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
return obbTransform.mapRect(clipRect);
}
return clipRect;
}
bool RenderSVGResourceClipper::pathOnlyClipping(GraphicsContext* context, const AffineTransform& animatedLocalTransform, const FloatRect& objectBoundingBox)
{
// If the current clip-path gets clipped itself, we have to fallback to masking.
if (!style()->svgStyle()->clipperResource().isEmpty())
return false;
WindRule clipRule = RULE_NONZERO;
Path clipPath = Path();
// If clip-path only contains one visible shape or path, we can use path-based clipping. Invisible
// shapes don't affect the clipping and can be ignored. If clip-path contains more than one
// visible shape, the additive clipping may not work, caused by the clipRule. EvenOdd
// as well as NonZero can cause self-clipping of the elements.
// See also http://www.w3.org/TR/SVG/painting.html#FillRuleProperty
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
RenderObject* renderer = childNode->renderer();
if (!renderer)
continue;
// Only shapes or paths are supported for direct clipping. We need to fallback to masking for texts.
if (renderer->isSVGText())
return false;
if (!childNode->isSVGElement() || !toSVGElement(childNode)->isStyledTransformable())
continue;
SVGStyledTransformableElement* styled = toSVGStyledTransformableElement(childNode);
RenderStyle* style = renderer->style();
if (!style || style->display() == NONE || style->visibility() != VISIBLE)
continue;
const SVGRenderStyle* svgStyle = style->svgStyle();
// Current shape in clip-path gets clipped too. Fallback to masking.
if (!svgStyle->clipperResource().isEmpty())
return false;
// Fallback to masking, if there is more than one clipping path.
if (clipPath.isEmpty()) {
styled->toClipPath(clipPath);
clipRule = svgStyle->clipRule();
} else
return false;
}
// Only one visible shape/path was found. Directly continue clipping and transform the content to userspace if necessary.
if (static_cast<SVGClipPathElement*>(node())->clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
AffineTransform transform;
transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
clipPath.transform(transform);
}
// Transform path by animatedLocalTransform.
clipPath.transform(animatedLocalTransform);
// The SVG specification wants us to clip everything, if clip-path doesn't have a child.
if (clipPath.isEmpty())
clipPath.addRect(FloatRect());
context->clipPath(clipPath, clipRule);
return true;
}
bool RenderSVGResourceClipper::applyResource(RenderObject* object, GraphicsContext* context)
{
ASSERT(object);
ASSERT(context);
m_clipper.add(object);
context->beginPath();
AffineTransform obbTransform;
FloatRect objectBoundingBox = object->objectBoundingBox();
bool bbox = static_cast<SVGClipPathElement*>(node())->clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX;
if (bbox) {
obbTransform.translate(objectBoundingBox.x(), objectBoundingBox.y());
obbTransform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
}
bool hasClipPath = false;
WindRule clipRule = RULE_EVENODD;
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
if (!childNode->isSVGElement() || !static_cast<SVGElement*>(childNode)->isStyledTransformable())
continue;
SVGStyledTransformableElement* styled = static_cast<SVGStyledTransformableElement*>(childNode);
RenderStyle* style = styled->renderer() ? styled->renderer()->style() : 0;
if (!style || style->display() == NONE)
continue;
Path pathData = styled->toClipPath();
if (pathData.isEmpty())
continue;
if (bbox)
pathData.transform(obbTransform);
hasClipPath = true;
context->addPath(pathData);
clipRule = style->svgStyle()->clipRule();
}
if (!hasClipPath) {
Path clipPath;
clipPath.addRect(FloatRect());
context->addPath(clipPath);
}
// FIXME!
// We don't currently allow for heterogenous clip rules.
// we would have to detect such, draw to a mask, and then clip
// to that mask
context->clipPath(clipRule);
return true;
}