Got the solution from support and thought I'd post it here in case anyone else runs into this.
For plugin-based custom shaders, the equivalent to setting the 'ui "mapping"' in an SPDL is to set a special undocumented attribute on the ShaderParamDef. The attribute name is {8C80DEF3-1064-11d3-B0B7-00A0C982A112} and the value is the GUID for the viewport ambient/diffuse/spec/whatever (you can find those from the softimage SPDL by searching for ui "mapping") Example: inputParamDefs.GetParamDefByName(L"diffuse").GetAttributes().Set(L"{8C80DEF3-1064-11d3-B0B7-00A0C982A112}", L"{3515CC72-082C-11D0-91DE-00A024C78EE3}"); -Nicolas On Thu, Apr 26, 2012 at 7:18 PM, Nicolas Burtnyk <nico...@redshift3d.com>wrote: > Hi everyone, > > For SPDL-based shaders, one can use the ui "mapping" statement to control > the viewport rendering of a shader. > Is there an equivalent mechanism for plugin-based shaders? > > Thanks! > > -Nicolas >