OpenGL Shading Issues on PPC
OpenGL Shading Issues on PPC
- Subject: OpenGL Shading Issues on PPC
- From: Peter Willsey <email@hidden>
- Date: Mon, 19 Apr 2010 09:33:15 -0700
Hello All,
I've been developing a screensaver in Objective-C using OpenGL to
render an object in wavefront .obj format. The object is displayed
and rotated on the X, Y and Z axis. I have enabled lighting and I'm
calculating surface normals so that shading works properly.
I have been developing this plugin on a 2.4Ghz Intel Core 2 Duo Mac
Book Pro with a GeForce 8600M GT video card with 256 MB of VRAM.
Everything was working great until I compiled a PPC version of my
screensaver and tried running it on my Power Mac G5 Tower with a
GeForce FX 5200 video card. The Screensaver loads and displays, but
there appears to be some issues with shading and lighting. As the
model rotates areas of the model flash, and dark colors pass over top
in strange patterns. From certain angles areas of the model almost
completely disappear.
Not sure if this is relevant, but I'm not using any textures in the
model. I've also tried importing the .obj file into a 3D program and
exporting it back into .obj format with vertex normals included in the
file, and using those instead of calculating surface normals myself.
I've tried using GL_FLAT and GL_SMOOTH shading models.
This does not occur on my Intel machine. Both machines are running
Mac OS X 10.5.8. I'm not sure if this is related to the video card,
the driver, the fact that the machine is a PPC or if it's just older
hardware that I should not try and support ?
Thanks
Peter
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden