View Full Version : Texture coordinates

12-10-2000, 07:03 PM
I know this is probably very basic, but what are texture coordinates?

I know how to texture map polygons. I know that I must specify coordinates for the polygon. lower left, right etc...(Are these the texture coordinates?)

However, I would like to figure out how to texture my models (loaded from 3D Studio max in ASE format) as I can in 3D studio max.

In other words, how can I use the whole texture coordinate thing to map textures across multiple triangles? Right now, I just texture each and every triangle. If I have a wall that I've loaded, I don't want to texture the 2 triangles that make the wall separatly. I would want to spread my texture across the 2 triangles.

I guess I'm a little confused on the different ways to implement texture mapping.

Any advice?

12-11-2000, 12:51 AM
Each triangle is textured separately from the others and that cannot be done in any other way.
But this is not a problem if the texture coordinates are calculated the right way. For instance, when you texture a quad (which is made of two triangles) with a bitmap image, the image appears correctly spread on both triangles and you don't see any artifact in it.
If you're not sure of how to use glTexCoord, got ot Chapter 8: http://helios.scripps.edu/cgi-bin/infosr...OpenGL_PG/17383 (http://helios.scripps.edu/cgi-bin/infosrch.cgi?cmd=getdoc&coll=0650&db=bks&fname=/SGI_Developer/OpenGL_PG/17383)
The ASE format can store texture coordinates. As 3ds max calculates this coordinates so that you get the right mapping across multiple triangles, you won't have any problem. Just use the texture coord provided in the ASE files (I assume you know how to use glTexCoord) and bind a texture before drawing your object.

12-11-2000, 03:41 AM
thank you....that should help me