Performance issue : Bake those chains!

Yedp

Hello, I want to do some chains for a project and I was wondering how to get the best effect possible for chains, performance-wise and visually-wise, so I tried a few options.
I never really tried to do such things before so I could definitly use some advices and help to chose what's best (sorry for the quality these were done for tests so they are pretty rough)



- Number 1 : High res model
- Number 2 : lower poly version with normal map - 576 triangles
- Number 3 : each piece is made from a cube with normal map + alpha - 192 triangles
- Number 4 : simple planes duplicated with normal map + alpha - 32 triangles
- Number 5 : two rectangles with normal + alpha - 24 triangles
- Number 6 : two planes with normal + alpha - 2 triangles

bugo

What is your end platform? Are you going to animate them or just static?

Yedp

these are going to be static but I'd like to be able to see them from several angle and keep a nice shape. I'm using Unity3D

bugo

When I say platform I mean, is it PC? is it Mobile? Is it Wii? What's your platform. If it's PC i would go for number 4, since you can rotate each one for different angles, and it's not so expensive. If it's mobile, 6.

Yedp

Hi bugo, sorry my english isn't that good :poly136:
Thanks for your reply! That's what I was looking for! I'm using it for PC, so I guess you are right number 4 would be fine, thanks again!

Out of curiosity what would be better if I had to animate them ? Number 6 with more divisions?

SlyRipper

Well if you use Unity you can do some tricks with it. Also if the chains are static you could easily go with number 2, the trick is to merge all chain parts together so you have just 1 mesh for the entire chain. This will cause unity to just have 1 drawcall for it (+ the ones for material, etc) the meshes are not that hard anymore for graphiccards.. so you can go up with those modeled chains and place them. Dunno if this still works for animationed chains, I guess you have to try. But the part you have to watch is the amount of placed chains, if you place hundreds of those chains then it might be better to use some of the later versions like nr6 with more divisions. Also try to keep the texture small and use a material that you've already used for other stuff, so you can save drawcalls there, too.

It takes much more to render a good material and textures than the mesh itself, so I would rather check the material+texture first than the mesh (still you have to watch, amount, tri-count, and stuff like that)

Timidy

Number 5 would be the best imo because you have depth from all angles. No. 6 looks too flat from the Y perspective, no depth.

To animate them, yes I would go for 5 or 6 with more divisions. Just place an edge at every place you would want the chain to bend or have a joint.

Noors

Depends of how much angle this could be animated. Sorry but animate a plane with subdivison would distort the faces badly. Not sure it has an interest over 4.
Never been a huge fan of this double mask trick. A normal map should already gives a decent relief. If you really need volume, then model it.
So i'd say 1,2,4,(6 if straight and static) and then it depends of the quality, budget...required

cryrid

An even more extreme iteration could be a single plane, treated as a billboard (but not on every axis). I think Skyrim did something similar for some of its chains.

poopipe

Bake it to 4 sided cylinder if you're not gonna get too close. you wont need alpha

Up close id go with number 2 . If the links were fatter you could go with 2 but made of closed boxes cos you probably wouldnt need the alpha there either

Synthesizer

If you can use LODs and want the best visual quality I'd go with 1->2->4->Cull away.