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DS development > Can I use different projection matrix in a single frame?

#144838 - Noda - Thu Nov 08, 2007 4:14 am

..that's my question, as I would like to display my 3D scene using a projection matrix, then change to an othogonal one with a different viewpoint to display some text/2D-style sprites.

Is it possible? (there's no info on that on the GBAtek reference..)

thanks!

EDIT: I got the answer by myself (testing): IT WORKS, that's a really great news for me (as I don't want to bother with the 2D harware, 3D is soo nice ^^)

#144876 - naleksiev - Thu Nov 08, 2007 8:18 pm

How much characters text you are expecting to have on the screen? If you have 150 it will be 10% of the total quads you can use.

#144879 - Noda - Thu Nov 08, 2007 9:33 pm

Not much, but even just using that to show some debug parameters can be time saving ^^

#144909 - M3d10n - Fri Nov 09, 2007 3:55 am

While it's much easier to draw text using quads, I recommend you at least start learning how to use sprites to do so. That'll give you 128 characters which can result in a max saving of 256 triangles (enough for a whole extra fairly detailed 3D model).

#144911 - Noda - Fri Nov 09, 2007 4:15 am

I don't need those triangles, and I can't use sprites, since I'm using 3D on both screens with 2 VRAM Banks assigned for textures. I know how to use sprites to display text, but that's just not adapted to my usage...