bsdf phong(float exponent, ...)
bsdf phong(vector nml, float exponent, ...)
See writing a PBR shader for information on BSDFs.
vector phong(vector nml, vector V, float shinyness, ...)
V represents the normalized vector from the surface to the eye (-normalize(I)). shinyness is the Phong exponent (typically around 20 or higher). roughness represents the surface roughness (typically 0 to 1).
Light inclusion/exclusion options
Specifies lights to include/exclude by their “category” tags.
This is the preferred include/exclude lights rather than pattern matching
light names with the
"lightmask" keyword argument.
diff = diffuse(nml, "lightmask", "hero | fill");
See light categories for more information.
When evaluating light and shadow shaders, objects have pre-defined light masks. This mask is usually specified in the geometry object and specifies a list of lights which are used to illuminate a surface or fog shader. It is possible to override the default light mask by specifying a “lightmask” argument.
diff = diffuse(nml, "lightmask", "light*,^light2");
…will cause all lights whose names begin with “light” except for a light named “light2” to be considered for diffuse illumination.
All Houdini scoping patterns, excepting group expansion, are supported:
*- wild-card match
?- single character match
^- exclusion operator
[list]- character list match