3 replies to this topic

[jim c]

I've got a long tunnel that I'd like to walk through. The tunnel is made of a cylindrical mesh with repeated arches. I'm repeating the arches with the Copy sop, and this makes for some pretty heavy geometry. Does it make more sense to use Instancing? So I would make one arch and then make copies with the Instance object? Is there any reason you wouldn't want to do that? Or any gotcha's that you need to be aware of at render time?

[Netvudu]

well, the main gotcha in my opinion is that with instances you are mostly limited to Transformation and/or shading changes per copy, while with Copy/stamping you can make ANY changes per copy.
This being said, if the arches are mostly the same by all means go for instances.

Also you can add some randomization on which object get instanced, so with 3 or 4 arches with slight differences on shading or position/rotation/scale nobody might ever suspect you are repeating models.

Resources-wise I haven´t been most succesful with instancing and memory handling in Mantra in the past, but I have yet to test H12 instances. Supposedly it has gotten much better.

my two euro cents.

Edited by Netvudu, 24 May 2012 - 07:52 AM.

[jim c]

Yeah the arches will be staying the same, I don't think I would need to change anything other than perhaps shader settings, but I probably won't event mess with that.

Of course another option would be to make the arch a DA and use the Delayed load technique. I've heard good things about this but never used it myself.

[Netvudu]

I tried it and well, Delayed Load is a way of instancing at render times, not really something that different, AFAIK. It´s usually the only way I instance.

Edited by Netvudu, 24 May 2012 - 08:04 AM.