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MARS_999

OpenGL Good tutorial on Scrolling and OpenGL

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MARS_999    1627
I am using SDL and OpenGL. I am looking to do a top down scroller, but can''t find any info on the subject? Also do you texture glRect() like you would a glBegin(GL_QUADS) routine? Thanks. Please forgive me! =)

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Brannon    122
I think in order to texture map a polygon, you must specify texture coords for each vertex.. otherwise how does OpenGL know how to apply the texture to your surface?

That said, I remember reading something in my OpenGL book about automatically figuring out texture coordinates. Look up the docs for glTexGen*(). Not sure if that will work though.

Is there some reason you don''t want to use GL_QUADS? You can always write a utility function to encapsulate the functionality into a single function call.


-Brannon

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MARS_999    1627
Now I would rather use GL_QUADS but not sure if I can us it in a Ortho projection? Thought Ortho was 2D? What I am trying to do is us teh Ortho to display a bitmap at my screen resolution I have set for a title page. Not sure on how to do it but would think using a glRect or GL_QUADS would work. But if GL_QUADS doesn't work with the Ortho projection then I guess I will have to use glRect? Hope that clears up what I am trying to do. =)

Please forgive me! =)

Edited by - Mars_999 on December 17, 2001 4:18:56 PM

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