Calling external library function from shader

What is the mechanism for making API call to external library at the shading language level?

E.g. I am writing a texture shader which needs to obtain its RGB values from a proprietary file format. The size of the file is typically in the hundreds of gigabyte, I don’t want to convert the file to JPEG/TIFF to be able to read them. I want to read them directly.

In the RenderMan shading language, there is DSO shadeop which allows one to write C/C++ functions which the shader can use.

Is there an equivalent in the OpenGL Shading Language?

Cheers

Nicholas Yue

OpenGL Shaders (potentially) run on seperate (non-CPU based) hardware, calling an external library would be very slow (and might be impossible, due to hardware restrictions).

Hence its not supported by OpenGL shaders and probably won’t be (if ever) for a long while.

[This message has been edited by DeanoC (edited 02-27-2003).]

[This message has been edited by DeanoC (edited 02-27-2003).]