Renderman - Documentation for UNC Comp238, Fall 99

Running renderman from a department *NIX machine

All executables are located in

 /usr/local/prman/bin 

which is a pointer to

 /afs/unc/pkg/prman/[PLATFORM]/prman.38d/bin 

Where [PLATFORM] is one of sgi, sun, or linux. So if you just add the short version to your $PATH, so should get the correct executables for any *NIX machine on afs.

The following is a sketch of the steps in coding and rendering a scene with Renderman. Note that the "Scene Code" and "Scene Exe" steps are optional: you can edit RIB files directly. Documentation for RIB files is not in the local docs, but may be available from Pixar(?). [Note: I just found a local example of a few RIB files here.]

               cc                run
SceneCode.c  ----->  SceneExe*  ------>  Scene.RIB -\
                                                     |
            'shader'                                 | 'render'
Shader.sl  ---------->  Shader.slo  -----------------+----------> Image
                                                     |
            'txmake'                                 |
Image.tif  ---------->  Image.tex  -----------------/

One other important file is rendermn.ini which lives in /usr/local/prman/etc/. This file contains all manner of default values used by the render script, including paths to shaders and such. Any value in it can be overridden by providing a new value in a rendermn.ini file in the current executing directory. You can also place a .renderman.ini file in your HOME directory for the same effect. This would be useful if, for example, you want to store your new shaders in their own directory.

*NEW* Note to clear up some confusion: The sample scene in /usr/local/prman/example/ will *not* compile successfully, because it uses several Pixar "looks" for its shaders, which are from a library we do not have. However, the samples in /usr/local/prman/tutorial/ch*/ should work, and may prove useful. Though you can probably figure out what to do from the README and Makefile included with each chapter, additional documentation (and a list of what's there) can be found online HERE.

*NEW* Another hint: to get most of the tutorial examples to run you need to have them output to a file instead of rendering to a 'framebuffer'. The quick fix is to edit the .c file and replace the line RiDisplay("RenderMan", RI_FRAMEBUFFER, "rgb", RI_NULL); with RiDisplay("filename", RI_FILE, RI_RGBA, RI_NULL);.

Further reference for all this information can be found in the Photorealistic RenderMan 3.8 User's Manual.

Pointers to Language Documentation

Reference for both the Shader Language and the Scene Language can be found in the RenderMan Interface 3.1 Specification.

A few especially helpful quick links from the RISpec:

• Section 8 - Types - ref for builtin types (color, point)
• Section 12 - Shader Execution Environment - lists of the "magic variables" that get passed in and out of shaders
• Section 13 - Language Constructs - includes vector operators and special lighting loops
• Section 14 - Shaders and Functions - has some info on how shaders are passed values
• Section 15 - Built-In Functions - useful things
• Appendix A - Standard RenderMan Interface Shaders - the builtin shaders are good simple examples of how a shader works
• Section 16 - Example Shaders - some more complex shaders, including a whitted rytracer

Also note: RendeMan 3.8 has some Extensions to the Shading language which are not in the 3.1 RISpec.

*NEW* Someone pointed out this page of Renderman Notes. It basically steps through a disciplined method of creating new shaders.