Does anybody know a definitive guide on combining models for batching?

Questions & Answers
1

Scripts, sharing materials, etc. What are the absolute best practices? Does anybody know how the fantastic Madfinger handles this?

(Given that I’ve already studied the following: ShadowGun: Optimizing for Mobile Sample Level | Unity Blog)

Follow-up: Any definitive documentation or experience on how dynamic batching works? I’m a little confused.

All the best,

–Rev

2

I don’t know of a definitive documentation for dynamic batching, but if you Google this list with “Dynamic Batching,” you will get 1000’s of hits. An hour of reading will give you a pretty good idea of what works and what doesn’t. Here are the high points I’ve gleamed:

Won’t work:

  • If the materials are different, the objects do not batch.
  • If you change any material attribute at runtime (color, texture, offset…), then the object gets a new instance of the material, and that object will no longer batch with the objects using the original material.
  • If you have more than 900 vertex attributes in your mesh, then the mesh won’t batch. For example if you are using both normals and uv in a mesh, then you can only have 450 vertices and have the object batch.
  • Submeshes that use different materials don’t batch together. Different material means different GPU call.
  • If you use Graphics.DrawMesh() to draw your mesh directly, the meshes don’t batch (even if they would batch if attached to a game object).
  • Sometimes objects that on paper should batch don’t for reasons unknown (or at least uncommented upon) to the list.

Will work:

  • You can change UV mappings at runtime without breaking batching.
  • You can change the vertex colors at runtime without breaking batching.
  • You can change the mesh itself at runtime without breaking batching (assuming you stay under the vertex limit).

One best practice: look into texture atlases to reduce draw calls.