struct CameraUniform {
    scale: vec2<f32>,
    offset: vec2<f32>,
};

@group(0) @binding(0) var<uniform> camera: CameraUniform;
@group(1) @binding(0) var quad_texture: texture_2d<f32>;
@group(1) @binding(1) var quad_sampler: sampler;

struct VertexIn {
    @location(0) position: vec2<f32>,
    @location(1) uv: vec2<f32>,
};

struct InstanceIn {
    @location(2) world_pos: vec2<f32>,
    @location(3) size: vec2<f32>,
};

struct VertexOut {
    @builtin(position) clip_position: vec4<f32>,
    @location(0) uv: vec2<f32>,
};

@vertex
fn vs_main(vin: VertexIn, iin: InstanceIn) -> VertexOut {
    var out: VertexOut;
    let world = iin.world_pos + vin.position * iin.size;
    let ndc = world * camera.scale + camera.offset;
    out.clip_position = vec4<f32>(ndc, 0.0, 1.0);
    out.uv = vin.uv;
    return out;
}

@fragment
fn fs_main(in: VertexOut) -> @location(0) vec4<f32> {
    let color = textureSample(quad_texture, quad_sampler, in.uv);
    if (color.a < 0.01) {
        discard;
    }
    return color;
}