I have a made an OpenGL application in WindowsXP that works superb in XP / Vista and Win7.
After altering a shader suddenly textures is VERY distorted in Vista and Win7 but works fine in XP.
The only big differense is that I have four texture samplers instead of three.
I thought that if a shader compiles and works on one system it should work the same on the other system. Or is it Microsoft that keeps adding a new dimension to “backwards compability”??
I know much changed in Vista and Win7 when it comes to OpenGL, but I didnt thought that a simple change in a shader could make such a difference.
ANY suggestions would be appreciated.
Why do you think Windows is at fault here at all? I’m guessing that these three OSs are not all installed on the same machine. So what are the other differences between the machines?
Well, the application has been tested on six setups and it works on the three with XP and not the three that doesnt has XP.
The XP machines has both ATI and nVidia cards.
I have even swapped graphics card in one of them to make sure it wasnt a nVidia/ATI problem as usual.
The only thing I havent been able to test is an ATI card on the non-XP machines.
nVidia GeForce 8800GT 512Mb Win7 Doesnt work
nVidia GeForce 9400M 256 Mb (mobile) Vista Doesnt work
nVidia GeForce 260 800Mb. Vista Doesnt work
nVidia QadroFX 4500 512Mb XP SP3 Works
ATI X850 256Mb XP SP3 Works
nVidia GeForce 5900 Ultra 256Mb XP SP3 Works
+an unknown ATI on another laptop with XP SP3 that also works.
I dont have the specs for the rest of the hardware, but Im quite sure thats not the problem.
To me the common problem seems the OS.
The 8800, 9400, and 260 are all DX10 parts. Which mean, particularly for OpenGL, they’ll likely use the same shader compiler/linker.
The QuadroFX 4500 and 5900 both are not DX10 parts, so they would use a different compiler/linker.
Looks like an NVIDIA driver bug. Maybe you should post the shader in the appropriate forum or send NVIDIA a bug report.
I dont have the specs for the rest of the hardware, but Im quite sure thats not the problem.
To me the common problem seems the OS.
However, since the driver (which is tied to the graphics hardware) is the one responsible for compiling a GLSL shader, and not the OS, the OS should only be considered the problem when all other avenues are exhausted.
