James Liu 12032cd296 Directly copy data into uniform buffers (#9865) ... # Objective This is a minimally disruptive version of #8340. I attempted to update it, but failed due to the scope of the changes added in #8204. Fixes #8307. Partially addresses #4642. As seen in https://github.com/bevyengine/bevy/issues/8284, we're actually copying data twice in Prepare stage systems. Once into a CPU-side intermediate scratch buffer, and once again into a mapped buffer. This is inefficient and effectively doubles the time spent and memory allocated to run these systems. ## Solution Skip the scratch buffer entirely and use `wgpu::Queue::write_buffer_with` to directly write data into mapped buffers. Separately, this also directly uses `wgpu::Limits::min_uniform_buffer_offset_alignment` to set up the alignment when writing to the buffers. Partially addressing the issue raised in #4642. Storage buffers and the abstractions built on top of `DynamicUniformBuffer` will need to come in followup PRs. This may not have a noticeable performance difference in this PR, as the only first-party systems affected by this are view related, and likely are not going to be particularly heavy. --- ## Changelog Added: `DynamicUniformBuffer::get_writer`. Added: `DynamicUniformBufferWriter`.		2023-09-25 19:15:37 +00:00
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macros	Fix the clippy::explicit_iter_loop lint (#9834)	2023-09-19 03:35:22 +00:00
src	Directly copy data into uniform buffers (#9865)	2023-09-25 19:15:37 +00:00
Cargo.toml	Bevy Asset V2 (#8624)	2023-09-07 02:07:27 +00:00