Calling RenderBox::absoluteQuads on RenderSVGRoot returns incorrect values when zoom or viewbox is involved

• Component: SVG
• Status: RESOLVED FIXED

[Max Vujovic]

RenderSVGRoot applies its local transform on itself when calling RenderBox::absoluteQuads. This happens in RenderSVGRoot::mapLocalToContainer.

The call hierarchy is:

RenderBox::absoluteQuads(Vector<FloatQuad>&, bool* wasFixed) const;
RenderObject::localToAbsoluteQuad(const FloatQuad& quad, bool fixed = false, bool* wasFixed = 0) const
RenderObject::localToContainerQuad(const FloatQuad&, RenderBoxModelObject* repaintContainer, bool fixed = false, bool* wasFixed = 0) const;
RenderSVGRoot::mapLocalToContainer(RenderBoxModelObject* repaintContainer, bool useTransforms, bool fixed, TransformState&, bool* wasFixed = 0) const;

absoluteQuads takes in a quad with the size of the SVG root element in screen space, after page zoom.
mapLocalToContainer then transforms the quad by RenderSVGRoot's m_localToBorderBoxTransform, which contains the zoom transform and the viewbox transform. See RenderSVGRoot::buildLocalToBorderBoxTransform.

Note that both getBoundingClientRect and the inspector highlight on SVG root elements rely on absoluteQuads to do their job. Links to related bugs are under the "Blocks:" field.

[Nikolas Zimmermann]

Is this bug fixed as well, now?

[Max Vujovic]

(In reply to comment #1)
> Is this bug fixed as well, now?

Yes, after bug 78037, this bug should be fixed.