Comment 11 for bug 412928

This would definitely be a very useful feature, especially when used in combination with path cloning to create shading. I don't know if it would make it into Inkscape since there's not really an exact SVG 1.1 equivalent (or an SVG 2.0 equivalent currently, although different compositing modes could be used to achieve the same result and the spec is still a draft).

That being said, I've created a patch using r11949 which adds a "Set Inverse Clip" option to the context (right-click) menu of an object. When clicked, the top-most path is turned into a clip path as normal, but a new "inkscape:inverse" attribute on the "clipPath" element is set to "true", and essentially anything contained within the clip path is composited out when rendered. Again, I'm not sure if this could, or even should, end up in Inkscape, but this patch may be helpful to anyone who is looking to use an inverse clip mechanism.