Yeah, I'm not sure we clearly understand where the bottleneck is on resize. I'm starting to think that it might be the compositing loop redrawing the new window to the front buffer, not the driver actually resizing the window. I find resizing to be un-noticeably fast on my system but I'm running an RV570 and a quad-core CPU; need to re-test on some slower hardware.
I need to learn more about gradients; right now I don't understand why we even need shaders. It seems like we should be able to draw triangles and let the interpolators do all the work; maybe there's an edge matching problem or something. All I can say right now is that it seems like we should be able to do something, but I haven't talked to the devs about the problems yet.
Trapezoids seem like they should be easy to break down to triangles as well and I know both hardware and software folks have worked very hard to make all the edges match in OpenGL; again, this is spoken with the clarity of ignorance
Also, again there are no EXA driver interfaces for trapezoids yet.