Plants, Landscaping, Entourage, and Radiance...]


I'm still a Radiance noob,

Better than being a Radiance boob, which is what I feel like half the time. =8-)

What I'm wondering is how to deal with
things such as landscaping, people, cars,...

I'm concerned that modeling these items
whole, and including them within the
scene, will add too much complexity to
the project and greatly increase
rendering times on large exterior views.

Radiance can handle the complexity, (i.e. the massive amount of polygons), no problem. What does happen is that the ambient calculation gets, as Greg likes to say, "nasty". Of course, as for most limitations in Radiance, the author has developed a tool for dealing with that. You can exclude materials from the ambient calculation. By specifying -ae (material) in your rpict/rtrace command (or by placing it in your .rif file (render= -ae [material]) you tell Radiance to apply the ambient (-av) value to all materials on the -ae line, thus skipping a whole lot of interreflection calculations.

Does everyone typically have these
items as whole Radiance models, instanced
into the 'scene'? Is this not a problem
due to Radiance's render engine's differences
from other 3D packages? What about the
repetitiveness apparent in an image when
the same tree/bush/person/car is used
over and over and over again? I see
some exterior renderings on Visarc's
website that have wonderful looking
trees, does anyone know how those
were done?

Generally, yes, these complex "library" items are instanced. This saves lots of memory. I have also read about people who write scripts that randomize the placement of these library items. By varying the tree instances over three or four distinct models, and further varying the scale & rotation of each instanced tree, you can create a very random look to your "forest", for example. AFAIK, the trees you see in Visarc's renderings are all 3D geometry. They pride themselves on creating everything and faking nothing. Amazing, yeah?

   Rob Guglielmetti
[email protected]