bevy/crates/bevy_wgpu/src/renderer/systems.rs

use bevy_asset::AssetStorage;
use bevy_render::{
    pipeline::{PipelineAssignments, PipelineCompiler, PipelineDescriptor},
    render_resource::EntityRenderResourceAssignments,
    Renderable,
};
use legion::prelude::*;

pub fn render_resource_sets_system() -> Box<dyn Schedulable> {
    SystemBuilder::new("update_render_resource_sets")
        .read_resource::<AssetStorage<PipelineDescriptor>>()
        .read_resource::<PipelineCompiler>()
        .read_resource::<PipelineAssignments>()
        .read_resource::<EntityRenderResourceAssignments>()
        .write_component::<Renderable>()
        .build(
            |_,
             world,
             (
                pipelines,
                pipeline_compiler,
                pipeline_assignments,
                entity_render_resource_assignments,
            ),
             _| {
                // PERF: consider doing a par-iter over all renderable components so this can be parallelized
                for compiled_pipeline_handle in pipeline_compiler.iter_all_compiled_pipelines() {
                    if let Some(compiled_pipeline_assignments) = pipeline_assignments
                        .assignments
                        .get(compiled_pipeline_handle)
                    {
                        let compiled_pipeline = pipelines.get(compiled_pipeline_handle).unwrap();
                        let pipeline_layout = compiled_pipeline.get_layout().unwrap();

                        for assignment_id in compiled_pipeline_assignments.iter() {
                            let entity = entity_render_resource_assignments
                                .get(*assignment_id)
                                .unwrap();
                            let mut renderable =
                                world.get_component_mut::<Renderable>(*entity).unwrap();
                            if !renderable.is_visible || renderable.is_instanced {
                                continue;
                            }

                            for bind_group in pipeline_layout.bind_groups.iter() {
                                renderable
                                    .render_resource_assignments
                                    .update_render_resource_set_id(bind_group);
                            }
                        }
                    }
                }
            },
        )
}