It works ! Running at 100.5 MHz (4x the vga pixel clock), the core displays a rotating 512 triangle-rabbit at 256*240*60Hz -- I'd love to attach a picture, but it is rotating too fast, and all i get is a blurred image.
To be totally honest, p&r chockes on some paths, and there are some glitches: the most triangle intensive lines shows some "holes" (you can see through the surface because some triangles were not drawn), and some lines edges spill ouside the triangles. The latter might be caused by fixed point arithmetic (for very flat triangles) or the failing timing constraints.
Again, I cannot attach the bit file, but it's on github (final.bit)
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