[QUOTE=KrisZero;1254796]i want to active and bind as much textures as possible and then just switch the sampler that uses a different unit in fragment-shader.
I have 2 Machines:
Windows 7 with Nvidia graphic card
On this machine I can (only) use 32 Texture Image Units.
Windows 7 and Arch-Linux with ATI graphic card
On this machine I can use 32 Texture Image Units too…
Why it’s the same? On both machines I can have max 32 Units and this ist ok but I want to know how to determine that.[/QUOTE]
GL_MAX_TEXTURE_IMAGE_UNITS is the maximum number of texture units which can be used from the fragment shader. There are similar variables for the other shaders, e.g. GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS for the vertex shader. GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS is the maximum number of texture units in total, and represents the (exclusive) upper bound for the argument to glActiveTexture().