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Graphics > Mode 7 in text mode?

#45601 - jormundgard - Sun Jun 12, 2005 4:51 pm

I was looking at some Mode 7-type effects in Rayman 3 (he's riding a snake through a swamp as if on jetskis). I was kind of surprised by what I saw though, because it looks like they are doing it on BG2 in BG mode 0, text mode, which (as far as I know) is unable to do rotation/scaling effects. And yet, I see writes to the BG2PA-D registers as well.

I thought for sure that one would need to do rotation and scaling to make a reasonable perspective effect. Could I be misreading the registers? Or is is actually possible to do this in more than just BG modes 2 and 3?

#45602 - strager - Sun Jun 12, 2005 5:23 pm

For most commercial mode 7 games, there is a background. That background is mode 0. The code is designed to switch modes on the horizon so that it seems more realistic. You are just seeing what occurs durring the VBlanking period, when the mode is 0 (the first scanline must be mode 0).

#45604 - jormundgard - Sun Jun 12, 2005 5:43 pm

Now I see it - it's jumping between BG0 and BG1 (at some vcount, I guess). Sorry for the confusion, I don't have a lot of practice with debuggers :).