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by derefr 2994 days ago
> GPUs can actually scan to a display from multiple framebuffers in different resolutions and color formats in the same time.

This is also how early SLI worked: each GPU has a framebuffer, one holding the "even" scanlines and one holding the "odd" scanlines. Each GPU does its own rendering work to its own framebuffer, each rendering a vertically-squashed scene, with one scene offset by one pixel vertically. The master GPU then interleaves the two framebuffers together (pulling data from the slave GPU's framebuffer over the SLI link) when outputting a field.

1 comments

To add to that, "early SLI" stands for Scan-Line Interleave, not Scalable Link Interface like it is now. CRT was some crazy shit to deal with. I'm glad I never had to deal with it.

If you ever wondered why some old Youtube video looked like crap and has lines that don't match up, interleaving was why.

Usually artifacts are not the result of using interleaved source but the result of recoding done wrong. I remember reading mencoder manual about "pulldown" and other recoding options.