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C/C++ > uhm.. about 90degree rendering stuff in C

#7160 - f00l - Tue Jun 10, 2003 9:37 pm

Hi could someboy tell me how the 90degree rendering tech stuff works ?

I want to make a game like : Catacomb Abyss, with 90degree rendering (I don't even know if it's called that way :P )

anywayz.. if you don't know what I mean , download this.. it's a demo of Catacomb Abyss from idsoftware :

http://www.dosgamesarchive.com/download/game/3


thx,

f00l
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woei!

#7161 - wizardgsz - Tue Jun 10, 2003 10:17 pm

90 degree rendering = ray casting

links (GBA listings):

http://linuxgamers.net/lsd/gba/raycaster/
http://www.l8night.co.uk/mwynn/gbadev/rayengine/index.html

Ga

==
http://www.geocities.com/gabriele_scibilia/

#7162 - f00l - Tue Jun 10, 2003 10:19 pm

hmm.. I know what raycasting is .. but somebody told me about this 90degree thing.. I guess he was wrong.. anywayz.. thnx for the links! :)
_________________
woei!

#7172 - Sweex - Wed Jun 11, 2003 12:50 pm

The "90 degree thing" is a trick to improve performance of raycasting on the GBA. Because it is faster to draw horizontal lines than vertical, what is done for ie. doom, is they draw everything 90 degrees rotated. This way, the engine draws horizontal lines instead of vertical. Now to get it displaying correctly, they use the rotation/scaling registers on the GBA (bitmap modes) and rotate it "back" 90 degrees.

#7195 - wizardgsz - Wed Jun 11, 2003 11:16 pm

I remember a "last ninja"-type demo on gbadev.org coded in isometric view using sprites for walls (using affine transformations) but I can't remember the name...
later...
Ga
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