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View Full Version : Help needed to port an application from GL to OpenGL



oortael
06-20-2001, 05:22 AM
I'd just like to start of by saying that I've been programming in C and using the graphis libraries for about 2-3 weeks, so I don't really know much except what I've read.

I have to update and expand an application that basicly just show particles (spheres) in a 3D world and enable the user to move around. Multiple factors force me to port the application from GL(SGI's IRIS GL) to OpenGL (I'm not sure which version of OpenGL is used here, all I was able to know is that it's the standart OpenGL that comes with SGI's IRIX 6.5).

The only documentation I have is what I can get at: http://techpubs.sgi.com
(note that I'm not able to use the 'toogl' aplication they have to convert GL calls into OpenGL ones)
Here is the probs I'm having right now, I might add more later.

Angle in GL: perspective ;in OGL: gluPerspective
I know that in GL the angle used is 1/10th of a degree, but I wasn't able to find what kind of angle it uses

Lookat command:
in GL: lookat(vx,vy,vx,px,py,pz,twist) , where v* are view point and p* reference point, and twist the angle of rotation.
in OGL: gluLookAt(vx,vy,vz,px,py,pz,upx,upy,upz) , where up* is the direction of the up vector.
I can't seems to find how to convert my twist angle into the xyz coordinate needed for the up vector.

In my defmaterial in GL I have 'emission' and I didn't found the OGL equivalent, same goes for 'lcolor' in my deflight.

Right now that's all, but I'm not finished yet, and I stil haven't figured out what I'll use for the windowing (I'll probably be using the X commands).

Any help appreciated...