Am Mittwoch, 12. März 2008 09:46:25 schrieb Chris Robinson:
I am not yet conviced that those patches are a good idea. Some time ago I
found that I need the full half pixel to make DCT happy. Furthermore I see
different behavior among drivers, e.g. my r200 driver doesn't need any
correction(it rather hurts instead), and the nvidia driver behaves odd on
very small render targets.
As I said on IRC, I am afraid that we have to do those position fixes per
driver. In the extension detection we have to draw a few points onto the back
buffer and read back the results, and then configure the offsets accordingly.
As I keep saying, we need proper tests for that. Your test to test the corner
points is a good start, but we also have to test offscreen targets of
different sizes(e.g. 1x1, 4x4, 16x16, ...), and we have to test all 3
codepaths(rhw, fixed function, shader).