bevy-aabb-instancing 0.1.0

Render millions of AABB instances in Bevy.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65

use crate::component::CuboidInstancesBuffer;

use bevy::{
    ecs::system::{lifetimeless::*, SystemParamItem},
    pbr::{SetMeshBindGroup, SetMeshViewBindGroup},
    prelude::*,
    render::{
        mesh::GpuBufferInfo,
        render_asset::RenderAssets,
        render_phase::{
            EntityRenderCommand, RenderCommandResult, SetItemPipeline, TrackedRenderPass,
        },
    },
};

pub(crate) type DrawCuboidInstances = (
    SetItemPipeline,
    SetMeshViewBindGroup<0>,
    SetMeshBindGroup<1>,
    DrawMeshInstanced,
);

pub(crate) struct DrawMeshInstanced;

impl EntityRenderCommand for DrawMeshInstanced {
    type Param = (
        SRes<RenderAssets<Mesh>>,
        SQuery<Read<Handle<Mesh>>>,
        SQuery<Read<CuboidInstancesBuffer>>,
    );

    #[inline]
    fn render<'w>(
        _view: Entity,
        item: Entity,
        (meshes, mesh_query, instance_buffer_query): SystemParamItem<'w, '_, Self::Param>,
        pass: &mut TrackedRenderPass<'w>,
    ) -> RenderCommandResult {
        let mesh_handle = mesh_query.get(item).unwrap();
        let instance_buffer = instance_buffer_query.get_inner(item).unwrap();

        let gpu_mesh = match meshes.into_inner().get(mesh_handle) {
            Some(gpu_mesh) => gpu_mesh,
            None => return RenderCommandResult::Failure,
        };

        pass.set_vertex_buffer(0, gpu_mesh.vertex_buffer.slice(..));
        pass.set_vertex_buffer(1, instance_buffer.buffer.slice(..));

        match &gpu_mesh.buffer_info {
            GpuBufferInfo::Indexed {
                buffer,
                index_format,
                count,
            } => {
                pass.set_index_buffer(buffer.slice(..), 0, *index_format);
                pass.draw_indexed(0..*count, 0, 0..instance_buffer.length as u32);
            }
            GpuBufferInfo::NonIndexed { vertex_count } => {
                pass.draw_indexed(0..*vertex_count, 0, 0..instance_buffer.length as u32);
            }
        }
        RenderCommandResult::Success
    }
}