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Klaus
07-17-2001, 06:45 AM
SGIs OpenInventor implementation is awfully slow on a GeForce3 graphics adapter.

I use SoQt and the problem occurs on
Win9x and Linux(drivers 12.51).

Does anyone have this problem too ?
Any ideas what the reason is ?

[This message has been edited by Klaus (edited 07-19-2001).]

cyclone
07-24-2001, 03:13 AM
It's something that I have noticed on a *LOT* of C++ class/API/engines that encapsulate Opengl's commands.

I think that generaly, the biggest slowdown on the majority of their C++ class/API/engines is in the "pre-culling" process (cf. for don't draw the majority of polygons that aren't on the view fustrum)
=> they want always make this "big culling" on software when hardware with T&L can make this very more speedly with the more simple and hardware accelerated fustrum culling ...

@+
Cyclone

Klaus
07-25-2001, 01:21 PM
Thanks cyclone for the answer,

i found the problem. I had to set the draw buffer to GL_BACK explicitely in SoQt's class Inventor/Qt/viewers/SoQtViewer.cpp in the actualRedraw method at the end of the method just before the actualRedraw call.

Don't know why this is necessary only on GeForce3.