Thank you for your example files, Emil. Those are appreciated.
I did not promote and set the "ogl_glsl_shader" rendering property of the geometry's material to display my GLSL shader.
But instead, I created a new SHOP type (Network type: GLSL shader) via File > New Asset... and directly assigned an instance of said type to my geometry.
Seems to work.
I still have a couple of questions though:
- Which approach should be preferred ("ogl_glsl_shader" vs. new SHOP type) and why?
- And how are my GLSL shaders supposed to blend with Houdini's natural lighting computations?
The doc recommends the use of built-in functions such as HOUassignLitOutput() (cf. http://www.sidefx.com/docs/houdini/shade/glsl.html#houdini-built-in-functions), but I could not make it work properly. When creating a new SHOP type, Houdini provides me with a default implementation for the fragment shader which involves the HOUassignOutputs() function. However, no matter how I try to edit its call, my geometry always appears completely flat (and so does Houdini's default GLSL shader).
Any help is welcome.