1#import bevy_pbr::{
2    mesh_functions,
3    view_transformations::position_world_to_clip
4}
5
6@group(2) @binding(0) var texture: texture_2d<f32>;
7@group(2) @binding(1) var texture_sampler: sampler;
8
9struct Vertex {
10    @builtin(instance_index) instance_index: u32,
11    @location(0) position: vec3<f32>,
12};
13
14struct VertexOutput {
15    @builtin(position) clip_position: vec4<f32>,
16    @location(0) world_position: vec4<f32>,
17    @location(1) color: vec4<f32>,
18};
19
20@vertex
21fn vertex(vertex: Vertex) -> VertexOutput {
22    var out: VertexOutput;
23
24    // Lookup the tag for the given mesh
25    let tag = mesh_functions::get_tag(vertex.instance_index);
26    var world_from_local = mesh_functions::get_world_from_local(vertex.instance_index);
27    out.world_position = mesh_functions::mesh_position_local_to_world(world_from_local, vec4(vertex.position, 1.0));
28    out.clip_position = position_world_to_clip(out.world_position.xyz);
29
30    let tex_dim = textureDimensions(texture);
31    // Find the texel coordinate as derived from the tag
32    let texel_coord = vec2<u32>(tag % tex_dim.x, tag / tex_dim.x);
33
34    out.color = textureLoad(texture, texel_coord, 0);
35    return out;
36}
37
38@fragment
39fn fragment(
40    mesh: VertexOutput,
41) -> @location(0) vec4<f32> {
42    return mesh.color;
43}