bevy/crates/bevy_ui/src/render/ui.wgsl

struct View {
    view_proj: mat4x4<f32>,
    world_position: vec3<f32>,
};
@group(0) @binding(0)
var<uniform> view: View;

struct VertexOutput {
    @location(0) uv: vec2<f32>,
    @location(1) color: vec4<f32>,
    @builtin(position) position: vec4<f32>,
};

@vertex
fn vertex(
    @location(0) vertex_position: vec3<f32>,
    @location(1) vertex_uv: vec2<f32>,
    @location(2) vertex_color: vec4<f32>,
) -> VertexOutput {
    var out: VertexOutput;
    out.uv = vertex_uv;
    out.position = view.view_proj * vec4<f32>(vertex_position, 1.0);
    out.color = vertex_color;
    return out;
} 

@group(1) @binding(0)
var sprite_texture: texture_2d<f32>;
@group(1) @binding(1)
var sprite_sampler: sampler;

@fragment
fn fragment(in: VertexOutput) -> @location(0) vec4<f32> {
    var color = textureSample(sprite_texture, sprite_sampler, in.uv); 
    color = in.color * color;
    return color;
}