This page contains information about the V-Ray TexOSL node.
Overview
The V-Ray TexOSL map can be used to load Open Shading Language OSL shader code files (.osl) or OSL object code files (.oso) and render them directly with V-Ray. It can be used with shaders that have simple color and float output parameters. These parameters are considered respectively as texture RGB and alpha outputs.
If the shader file describes a material (rather than a texture) and writes its result in an output closure color parameter, it is advised to use the V-Ray OSL Material. Otherwise, the texture map will not evaluate the materials and will be rendered black.
For more on OSL in general, see the Github reference.
OSL Code
OSL Source – Determines how the OSL code is drawn.
Inline OSL
File path (.oso/.osl)
OSL Code – A space for manual insertion of an OSL code.
Path to .oso/.osl file – Specifies the .osl or .oso file which contains the shader (object) code.
Color & Alpha Tweaks
These rollouts are the standard V-Ray for Houdini texture rollouts.
Notes
The V-Ray TexOSL texture automatically compiles OSL shaders to object code (OSO format) upon shader selection. No following compilations occur (even at render events). If the loaded OSL shader is modified click the Recreate attributes button for your changes to take effect.
An OSL compiler that translates *.osl files to *.oso files can be found in the tools subdirectory of V-Ray's root installation folder.
References
OSL home page at SPI - Open Shading Language home page at Sony Pictures Imageworks
OSL Google Code page - Google Code project page for Open Shading Language
OSL GitHub page - GitHub project page for Open Shading Language