From: Paul Brannan <pbrannan@...>
Date: 2003-05-28T21:54:14+09:00
Subject: Re: OpenGL and large texture bitmaps

On Wed, May 28, 2003 at 01:00:00PM +0900, Joel VanderWerf wrote:
> Paul Brannan wrote:
> >What graphics hardware are you using?  IIRC, many of the Voodoo-based
> >cards cannot handle textures larger than 256 pixels square.
> 
> Ah. It's an Intel 815 (on a 2 yr old sony laptop). I will try to find 
> someone at work with a decent card.

I don't know of any such limitations on the i815 chipset, but I'm not up
on laptop graphics.

> Anyone happen to know an other way of displaying a bitmap as a 
> background for an OpenGL scene?

You can load the images as separate 256x256 textures, and display the
image using multiple polygons instead of a single rectangle.  This will
ensure that your code will work on a wide range of graphics hardware.
You should be careful with the way you scale the images, so that no
seams appear between them.

A better solution might be to use glDrawPixels to draw the background
image.

A final alternative is to use non-opengl primitives to draw the
background image, then use opengl to draw your scene.

> (I guess I should ask this on comp.something.else.)

Probably so.

Paul