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Lance
02-27-2004, 12:14 PM
I tried using the QGLWidet, but rendering a triangle with red, blue, and green verticies shows up as all one color - I was expecting a gradient between the verticies.

This works in my program outside of qt, and other GL programs also show color gradients.

Perhaps QT is not using the same GL rendering engine Mesa)? Maybe I need to buy QT's OpenGL module (but example GL programs work)?

I'm using RedHat9.0 which has qt-3.1 and XFree86-Mesa-libGL-4 and XFree86-4.3 (I've installed nVidia's drivers for the GeForce MX card).

Lance
02-27-2004, 12:16 PM
Question persists, just replying as a newly registered forum member with email lance@acm.org. Thanks, -Lance.

I tried using the QGLWidet, but rendering a triangle with red, blue, and green verticies shows up as all one color - I was expecting a gradient between the verticies.

This works in my program outside of qt, and other GL programs also show color gradients.

Perhaps QT is not using the same GL rendering engine Mesa)? Maybe I need to buy QT's OpenGL module (but example GL programs work)?

I'm using RedHat9.0 which has qt-3.1 and XFree86-Mesa-libGL-4 and XFree86-4.3 (I've installed nVidia's drivers for the GeForce MX card).

shinpaughp
02-27-2004, 09:28 PM
To my knowledge, Qt does not use MESA but the standard OpenGL headers and libs. Why use MESA? It is to the best of my knowledge a software implementation of OpenGL. And don't buy the Qt package... Qt free version is not broke or crippled in Linux (only Windows version is limited with 30 day trial) and should be same as what would be purchased minus tech support.

If the standard GL libs does not work, try posting some code...

good luck

Deiussum
03-01-2004, 05:44 AM
How are you specifying the colors? Do you have lighting enabled? Are you using smooth shading or flat shading?

[This message has been edited by Deiussum (edited 03-01-2004).]