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View Full Version : Bullet - Stand in - Proxy Objects



tcoursey
03-02-2012, 10:11 AM
I'm looking for a way to have bullet perform it's dynamics on a proxy object and then replace with instances.

I've tried a simple disc (which would allow me rotation and placement with instancing) but bullet doesn't seem to like anything without a volume. I've also tried simple points and 1 point polys. Both didn't work.

Any thoughts? It seems there was a way with MetaFX or something to have a proxy object.

-FP-
03-02-2012, 04:38 PM
Bullet practically demands a closed, watertight mesh.
Try a primitive.

tcoursey
03-04-2012, 08:54 AM
I've found a great way to use a proxy object of sorts. I'm able to now simulate with bullet 1,000's of proxys and then replace with my extremely high res objects at render time with Instancing. Works great!

chco2
03-04-2012, 02:54 PM
Why not share this ?


I've found a great way to use a proxy object of sorts. I'm able to now simulate with bullet 1,000's of proxys and then replace with my extremely high res objects at render time with Instancing. Works great!

tcoursey
03-04-2012, 03:00 PM
I was just waiting for someone to ask!

So I tried many many things. Particles and flat polys as mentioned don't work with Bullet. I was thinking there has to be a way (maybe not intended..but a way right).

So I started playing with volume geometry, things bullet would work with. Wanting to use instancing in I found the following to work for me.

I made a shape the same volume and similar shape to my end object I wanted to instance. I named all the surfaces on the object "delete" so I could select by surface later. I made a single poly in the middle of this object called "instance".

I welded everything together (a simple box in my situation). Ran bullet and had it solve my geometry.

Then brought that frozen (trans object) into modeler, selected all the "delete" geometry and was left with single polys that I could assign instancting too and use align to normal.

Set that object to not render and walah! I have 1,000's of very high resolution objects that have been solved by Bullet. May not work for every situation but should work for most.

Good luck!

CaptainMarlowe
03-05-2012, 05:30 AM
Interesting. Thanks for sharing.