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Graphics > Question about Vsync

#45984 - whodoo - Fri Jun 17, 2005 3:16 pm

This is probably a stupid question. When I've waited for VSync and the screen has been drawn, how long time will elapse until the screen starts redrawing again? I assume the screen isn't being redrawn continously, since I need a little time to change the backgrounds/sprites. Thank you!

#45985 - tepples - Fri Jun 17, 2005 3:47 pm

There are 160 scanlines in draw, and there are 68 scanlines in vblank. There are 1232 cycles in each scanline. If you're wondering whether you have time to load new sprite cels and animate background tiles, you have more than enough; see my white paper on the topic. Besides, unlike GBC VRAM, GBA VRAM is dual-ported, so even if you go over the vblank time, everything should still look OK (albeit with a bit of minor tearing if the top of the screen doesn't get updated first).
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