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Ace_Man
11-22-2000, 01:43 PM
It appears that the ASE file format is very straightforward, but I'm getting varied results.

I've written an ASE parser to load my models in my OpenGl program. I store all the vertices in an array as well as the face index values in a separate arrray.

I assumed all I would have to do is have loop that cycled through all the different vetex values in the right order (and draw triangles each time). I thought that the ASE format simply broke the model down into lots of trianlges.

If I load a simple box, then my parser works just fine. If I load anything else (sphere, cone, much less anything complex) I get distorted modls or nothing at all. Am I misinterpreting how the model is broken down when it is stored in the ASE file format?

Any suggestions as to why only a box works?

Bob
11-22-2000, 09:27 PM
Yes, the .ASE format is strightforward. But to get desired result, you might have to know a little bit on how the exporting tool works aswell. What you mean by "distorted object" isn't clear in your post, but one trap that people usually fall into when loading .ASE-files exported form 3D Studio MAX (don't know about other tools, because I haven't used any other) is that 3DS MAX uses a different coordinate system than OpenGL, and you have to do the conversion bethwen these two yourself. 3DS MAX uses the X-Y-plane as ground plane, and Z-axis as up-vector. OpenGL uses the X-Z-plane as ground plane and Y-axis as up-vector. This is why models looks strange when loaded directly into the wrong coordinate system. It's rotated 90 degrees and scaled by -1 in some direction. And since the cube is symetric in all three axes, it will look the same even though it's distroted.
Make sure you convert the coordinate system if you need to.

Have a look at nate.scuzzy.net (http://nate.scuzzy.net) , there you can find an excelent tutorial/sample code on how to load .ASE files.