[Radiance-general] Mesh Rendering Performance

[Greg Ward]

Hi Lars,

The only part that is common between a Radiance triangle mesh and an  
octree (as used for an instance primitive) is the octree data  
structure itself.  The mesh is stored very differently from a set of  
Radiance primitives -- a quick look at src/common/mesh.h should  
convince you of that.  I had to add a function pointer to the RAY  
structure in order that the specialized intersection routine would be  
called, interpreting the OBJECT id's as indices into the mesh patch  
list.

Other than the different primitive name, you can treat meshes just  
like instances.  Is it so inconvenient to swap the primitive name?   
It was a bit of work to get them to look and behave the same...  Now  
you want them to be the same?

I'm confused.
-Greg

> From: Lars O. Grobe <grobe at gmx.net>
> Date: February 26, 2006 3:39:29 AM PST
>
> Hi Greg, hi group.
>
>> The other thing that costs is transforming the ray before and  
>> after intersection, similar to having an octree instance (which it  
>> is).
>
> Hm, as we are on that topic... why do we need an extra primitive  
> for these precompiled meshes? It would be so nice to treat them  
> just like instances. Obj2mesh is just some kind of a different  
> oconv, that allows to get some information into the octree that  
> would be lost if we used obj2rad, because radiance scene has no  
> vocabulary for it, right?
>
> CU Lars.