Combining Meshs

Hello.

Following the "Optimizing Graphics performance Manual", I would like to combine meshs similar meshs to save some CPU calculations.

In my case, I have a set of trees generated around my map, theses trees can be attacked by the player and destroyed. Theses tree share the same material and have 3 states, "New", "Broken" and "Destroyed", each state has is own mesh but still share the same texture.

I have two questions about it.

1 : If I combine thoses trees, does each tree still keep his own collision box and scripts or does it make all tree to be one single game object ? Will each tree still be able to change his own state ?
2 : If I combine all trees into one mesh, does trees that are out of the screen will still be ignored for rendering ?


Thanks for your help.

 

Hello karl.jones

Thanks for your answer. I'm just a little confused by the doc you linked.

There is multiple clues here that let me think this is not for my case :
1 - I do not create the level in editor, instead I do have a procedural system that will places trees around the map in different place each time the game starts (this suppose that the transform moves one time in the game, once at start)
2 - Once the level as been generated, trees does not move their transform, but they do have animations. Is that a limitation?
3 - Trees can changes their mesh during the game (going from "New state" to "Broken state"). It's still the same game object, but it's not the same mesh displayed.

Let me know if I'm wrong, I'ld love to benefit from static batching
Thanks.

 

Static batching are by nature batching of objects that are static - they don't move. If you animate your trees, they're definitely moving.

What you can get, on the other hand, is dynamic batching, which batches together moving objects. The link karl.jones posted contains info about dynamic batching. See the information there about how to make objects do dynamic batching. Try to set up your trees to benefit, and check the frame debugger to see if they're getting drawn in the same call.

For performance, it's just as important to make sure that each individual tree is a single mesh. Note that if you have several materials (several submeshes), you'll get several draw calls per tree.