Integration with Houdini

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See also "Whats New Houdini"

Vex, Otl and Ifd Files

In addition to using vcc to compile vex shaders for Houdini, Cutter can also directly test your shaders with Mantra via ifd scripts. Cutter can also invoke Houdini's rmands utility after a shader has been compiled to append or create an otl file.

When a .vfl source code file is compiled via Cutter the compiled code can be either combined with an existing otl file or it can create a new otl that is specific to the shader being compiled. Refer to the Houdini section on the whats new index page.

Rsl and Otl Files

Houdini relies on otl files to "import" GUI information and vex shaders. A similiar situation exists for RenderMan Rsl shaders. However, in the case of RenderMan, an otl only contains GUI information. The compiled shader is not contained within an otl but remains in the directory into which it was originally compiled. When a rib file references a shader, prman must be able to "find" it as a result of looking at its shader searchpaths.

A Houdini environment variable HOUDINI_RI_SHADERPATH must be set with the appropriate informaion in order for Houdini to place information into a rib file ie.

    Option "searchpath" "shader" "HOUDINI'S_PATH_INFO"

Ideally, the HOUDINI_RI_SHADERPATH variable should be set permanently. However, if you are not able to modify your systems environment variables you can run either of the two following scripts. They setup the HOUDINI_RI_SHADERPATH and then launch Houdini. For Windows simply double click on the bat file. For linux, cd to the script directory and then enter,


Windows - Save as setup_houdini.bat


Linux - Save as

export HOUDINI_RI_SHADERPATH=@:$HFS/houdini/ri_shaders:~/PATH_TO_YOUR_SHADERS:RATTREE/lib/shaders

© 2002- Malcolm Kesson. All rights reserved.