# Objective
Bevy does ridiculous amount of drawcalls, and our batching isn't very
effective because we sort by distance and only batch if we get multiple
of the same object in a row. This can give us slightly better GPU
performance when not using the depth prepass (due to less overdraw), but
ends up being massively CPU bottlenecked due to doing thousands of
unnecessary drawcalls.
## Solution
Change the sort functions to sort by pipeline key then by mesh id for
large performance gains in more realistic scenes than our stress tests.
Pipelines changed:
- Opaque3d
- Opaque3dDeferred
- Opaque3dPrepass
---
## Changelog
- Opaque3d drawing order is now sorted by pipeline and mesh, rather than
by distance. This trades off a bit of GPU time in exchange for massively
better batching in scenes that aren't only drawing huge amounts of a
single object.
2a1ebc4ac4