Source/WebCore/rendering/svg/RenderSVGModelObject.cpp

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#include "config.h"
#include "RenderSVGModelObject.h"

#include "RenderLayerModelObject.h"
#include "RenderSVGResource.h"
#include "SVGNames.h"
#include "SVGResourcesCache.h"
#include "ShadowRoot.h"
#include <wtf/IsoMallocInlines.h>

namespace WebCore {

WTF_MAKE_ISO_ALLOCATED_IMPL(RenderSVGModelObject);

RenderSVGModelObject::RenderSVGModelObject(SVGElement& element, RenderStyle&& style)
    : RenderElement(element, WTFMove(style), 0)
{
}

LayoutRect RenderSVGModelObject::clippedOverflowRectForRepaint(const RenderLayerModelObject* repaintContainer) const
{
    return SVGRenderSupport::clippedOverflowRectForRepaint(*this, repaintContainer);
}

Optional<FloatRect> RenderSVGModelObject::computeFloatVisibleRectInContainer(const FloatRect& rect, const RenderLayerModelObject* container, VisibleRectContext context) const
{
    return SVGRenderSupport::computeFloatVisibleRectInContainer(*this, rect, container, context);
}

void RenderSVGModelObject::mapLocalToContainer(const RenderLayerModelObject* ancestorContainer, TransformState& transformState, MapCoordinatesFlags, bool* wasFixed) const
{
    SVGRenderSupport::mapLocalToContainer(*this, ancestorContainer, transformState, wasFixed);
}

const RenderObject* RenderSVGModelObject::pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap& geometryMap) const
{
    return SVGRenderSupport::pushMappingToContainer(*this, ancestorToStopAt, geometryMap);
}

// Copied from RenderBox, this method likely requires further refactoring to work easily for both SVG and CSS Box Model content.
// FIXME: This may also need to move into SVGRenderSupport as the RenderBox version depends
// on borderBoundingBox() which SVG RenderBox subclases (like SVGRenderBlock) do not implement.
LayoutRect RenderSVGModelObject::outlineBoundsForRepaint(const RenderLayerModelObject* repaintContainer, const RenderGeometryMap*) const
{
    LayoutRect box = enclosingLayoutRect(repaintRectInLocalCoordinates());
    adjustRectForOutlineAndShadow(box);

    FloatQuad containerRelativeQuad = localToContainerQuad(FloatRect(box), repaintContainer);
    return LayoutRect(snapRectToDevicePixels(LayoutRect(containerRelativeQuad.boundingBox()), document().deviceScaleFactor()));
}

void RenderSVGModelObject::absoluteRects(Vector<IntRect>& rects, const LayoutPoint& accumulatedOffset) const
{
    IntRect rect = enclosingIntRect(strokeBoundingBox());
    rect.moveBy(roundedIntPoint(accumulatedOffset));
    rects.append(rect);
}

void RenderSVGModelObject::absoluteQuads(Vector<FloatQuad>& quads, bool* wasFixed) const
{
    quads.append(localToAbsoluteQuad(strokeBoundingBox(), UseTransforms, wasFixed));
}

void RenderSVGModelObject::willBeDestroyed()
{
    SVGResourcesCache::clientDestroyed(*this);
    RenderElement::willBeDestroyed();
}

void RenderSVGModelObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
{
    if (diff == StyleDifference::Layout) {
        setNeedsBoundariesUpdate();
        if (style().hasTransform())
            setNeedsTransformUpdate();
    }
    RenderElement::styleDidChange(diff, oldStyle);
    SVGResourcesCache::clientStyleChanged(*this, diff, style());
}

bool RenderSVGModelObject::nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation&, const LayoutPoint&, HitTestAction)
{
    ASSERT_NOT_REACHED();
    return false;
}

static void getElementCTM(SVGElement* element, AffineTransform& transform)
{
    ASSERT(element);

    SVGElement* stopAtElement = SVGLocatable::nearestViewportElement(element);
    ASSERT(stopAtElement);

    AffineTransform localTransform;
    Node* current = element;

    while (current && current->isSVGElement()) {
        SVGElement& currentElement = downcast<SVGElement>(*current);
        localTransform = currentElement.renderer()->localToParentTransform();
        transform = localTransform.multiply(transform);
        // For getCTM() computation, stop at the nearest viewport element
        if (&currentElement == stopAtElement)
            break;

        current = current->parentOrShadowHostNode();
    }
}

// FloatRect::intersects does not consider horizontal or vertical lines (because of isEmpty()).
// So special-case handling of such lines.
static bool intersectsAllowingEmpty(const FloatRect& r, const FloatRect& other)
{
    if (r.isEmpty() && other.isEmpty())
        return false;
    if (r.isEmpty() && !other.isEmpty()) {
        return (other.contains(r.x(), r.y()) && !other.contains(r.maxX(), r.maxY()))
               || (!other.contains(r.x(), r.y()) && other.contains(r.maxX(), r.maxY()));
    }
    if (other.isEmpty() && !r.isEmpty())
        return intersectsAllowingEmpty(other, r);
    return r.intersects(other);
}

// One of the element types that can cause graphics to be drawn onto the target canvas. Specifically: circle, ellipse,
// image, line, path, polygon, polyline, rect, text and use.
static bool isGraphicsElement(const RenderElement& renderer)
{
    return renderer.isSVGShape() || renderer.isSVGText() || renderer.isSVGImage() || renderer.element()->hasTagName(SVGNames::useTag);
}

// The SVG addFocusRingRects() method adds rects in local coordinates so the default absoluteFocusRingQuads
// returns incorrect values for SVG objects. Overriding this method provides access to the absolute bounds.
void RenderSVGModelObject::absoluteFocusRingQuads(Vector<FloatQuad>& quads)
{
    quads.append(localToAbsoluteQuad(FloatQuad(repaintRectInLocalCoordinates())));
}
    
bool RenderSVGModelObject::checkIntersection(RenderElement* renderer, const FloatRect& rect)
{
    if (!renderer || renderer->style().pointerEvents() == PointerEvents::None)
        return false;
    if (!isGraphicsElement(*renderer))
        return false;
    AffineTransform ctm;
    SVGElement* svgElement = downcast<SVGElement>(renderer->element());
    getElementCTM(svgElement, ctm);
    ASSERT(svgElement->renderer());
    return intersectsAllowingEmpty(rect, ctm.mapRect(svgElement->renderer()->repaintRectInLocalCoordinates()));
}

bool RenderSVGModelObject::checkEnclosure(RenderElement* renderer, const FloatRect& rect)
{
    if (!renderer || renderer->style().pointerEvents() == PointerEvents::None)
        return false;
    if (!isGraphicsElement(*renderer))
        return false;
    AffineTransform ctm;
    SVGElement* svgElement = downcast<SVGElement>(renderer->element());
    getElementCTM(svgElement, ctm);
    ASSERT(svgElement->renderer());
    return rect.contains(ctm.mapRect(svgElement->renderer()->repaintRectInLocalCoordinates()));
}

} // namespace WebCore