Meaning of texture coordinates in "texture2D"

[prunkdump]

I have just two openGL implementation on my system :
-> my geforce 6600 driver witch support GL 2.1 and GLSL 1.20
-> the mesa driver that emulate GL 3.0 and GLSL 1.30

So in reality I'm limited to GL3.0 for debugging and GL2.1 for performance analysis....

[Alfonse Reinheart]

FYI: you can buy GL 4.3 hardware for like $40-50; it'll even be faster than your GeForce 6600.

Also, there are a lot of additions from higher GL versions that aren't hardware-specific. You can use them via core extensions, so that when you upgrade your hardware, you won't even have to change your code.

[prunkdump]

FYI: you can buy GL 4.3 hardware for like $40-50; it'll even be faster than your GeForce 6600.

Thanks ! But the geforce 6600gt is a agp card not a pci-express one ..... I need to update my whole configuration