performance wise - 20 separate objects or 1 merged?

[Fallen667]

I wanna make pile of bones on the floor.. is it, performance wise, better to make a skull, a bone and a ribcage, then place them in a pile in editor, that way you have more options, or is it better to do lets say three different piles in maya then merge then to one object and place one object??
Bone pile is just an example.. was wondering in general about that..

[Piranhi]

I 'think' it's better to just make the skull, bone, ribcage and then combine them to make a variety of different objects such as a pile of bones with a skull on top etc. I know the biggest hit on performance is the first instance of an object, after that, you can replicate that object many times with practically no extra performance hit.

[Crozz]

I think it would depend on the number of materials you use on the object. If you have like only a "bone" material, and don't add tons of others like "flesh", "worms" etc, then it would be ok to do many objects. But if you have lots of materials on one model the performance will hit you just as hard with every copy. (this is different from performance hit of the object itself).

[rfletchr]

heres an interesting article on this very subject :)

http://www.hourences.com/book/tutorialsmeshrendering.htm

[urgrund]

yes, but that tutorial focuses on UE2 tech.
It would be good to get a rundown on UE3 tech.

Although you can instance static meshes to save memory, does UE3 support any type of shader/hardware/stream instancing? Although each mesh will be lit uniquely when baked, this can just be streaming data associated with an instance ID - so, you could still render several pillars in one draw call indexing an array of lightmaps/baked lighting data.

This information would be very good to know to plan ahead - I haven't used UE3 that long, so I'm only speculating based on other engines I've used and a little engine programming I've done with batch renderers.

At the least - that tutorial goes over some very fundamental design principles for ame art that holds true in almost any engine you use! Very handy for artists to read through! :)

[KazeoHin]

If the a group of objects are going to be in the player's view all at once and use the same material, than they should be the same mesh, if it is going to be a huge pile that will likely occlude and be occluded in many different ways, try to break it up into a handful of separate meshes.