James Liu bd615cbf8c Shrink DrawFunctionId (#6944) ... # Objective This includes one part of #4899. The aim is to improve CPU-side rendering performance by reducing the memory footprint and bandwidth required. ## Solution Shrink `DrawFunctionId` to `u32`. Enforce that `u32 as usize` conversions are always safe by forbidding compilation on 16-bit platforms. This shouldn't be a breaking change since #4736 disabled compilation of `bevy_ecs` on those platforms. Shrinking `DrawFunctionId` shrinks all of the `PhaseItem` types, which is integral to sort and render phase performance. Testing against `many_cubes`, the sort phase improved by 22% (174.21us -> 141.76us per frame).  The main opaque pass also imrproved by 9% (5.49ms -> 5.03ms)  Overall frame time improved by 5% (14.85ms -> 14.09ms)  There will be a followup PR that likewise shrinks `CachedRenderPipelineId` which should yield similar results on top of these improvements.		2022-12-20 15:40:42 +00:00
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draw_state.rs	Add multi draw indirect draw calls (#6392)	2022-10-28 22:43:16 +00:00
draw.rs	Shrink DrawFunctionId (#6944)	2022-12-20 15:40:42 +00:00
mod.rs	Fix clippy::iter_with_drain (#6485)	2022-11-06 01:42:15 +00:00