unit processing and viewport

[Thierry Kormann <Th...@sophia.inria.fr>]

Hi,

In order to implement 'userSpaceOnUse' and 'objectBoundingBox' on pattern, mask 
and clipPath, I have added two methods in the BridgeContext.

get/setCurrentViewport. Those methods provide a way to access and modify the 
current viewport (used to compute percentages and units).

The current viewport is updated in the SVGSVGElementBridge (as <svg> starts a 
new viewport).

To implement 'userSpaceOnUse' and 'objectBoundingBox', the idea is to set the 
viewport to the clipped element's viewport (and not the clipPath's viewport).

Additional details: The UnitProcessor now uses the new method 
Context.getViewport() instead of svgelement.getOwnerSVGElement() to get the 
viewport to use.

No regression has been detected.

Thierry.

-- 
Thierry Kormann
email: Thierry.Kormann@sophia.inria.fr  http://www.inria.fr/koala/tkormann/
Koala/Dyade/Bull @ INRIA - Sophia Antipolis