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Beginners > Switch from Mode 4 in Mode 3

#53984 - Tomik - Wed Sep 14, 2005 8:44 am

Hi out there,
is it possible to switch in one programm from Mode 4 into MOde 3 ??

Code:
if(yes) how;


Thanks, Thomas

#53999 - kusma - Wed Sep 14, 2005 1:07 pm

Code:
if (yes) SetMode(MODE_3);


that is, if you use libgba.

#54072 - Cearn - Thu Sep 15, 2005 9:57 am

Merely setting the video mode isn't enough; all the drawing functions will still think it's mode 4. OK, technically the screen will use mode 3, but you'll just end up with garbage.

It's may be possible to go from mode 4 to mode 3, but it largely depends on the code existing code. If you're relying on specific mode 4 things like palette animation, you can pretty much forget it. If you're merely drawing things, it may be possible.
If you've used a sensible naming scheme for all the drawing functions (say "m3_xxx" for mode 3 functions, "m4_xxx" for mode 4 functions) you can do a global search and replace to change all the prefixes.

Of course, you'll also need to use the actual colors for the pixels, rather than palette indices, but if the code's still simple, that shouldn't be too hard.

And there's no flipping buffers, that'll have to be removed as well.