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MarkElendt

Mario, you might want to talk about how parameters are handled in VEX vs. RenderMan at some point. In VEX, the parameter values are passed verbatim into the shader. Thus, if you specify a vector of {0,0,1}, that's the value you get in the shader. RenderMan on the other hand, will transform the parameters into the space of the shader automatically for you.

JasonIversen

You're right - you sometimes have to hide vectors in color datatypes in RenderMan in order to avoid them being transformed. It's been a while since I wrote a RenderMan shader so maybe someone else can remember those cases and how to do it?