struct VertexInput {
    @location(0) position: vec3<f32>,
    @location(1) color: vec3<f32>,
};

struct InstanceInput {
    @location(5) model_row0: vec4<f32>,
    @location(6) model_row1: vec4<f32>,
    @location(7) model_row2: vec4<f32>,
    @location(8) model_row3: vec4<f32>,
};

struct VSOutput {
    @builtin(position) position: vec4<f32>,
    @location(0) color: vec3<f32>,
};

@vertex
fn vs_main(vertex: VertexInput, instance: InstanceInput) -> VSOutput {
    var out: VSOutput;
    let model = mat4x4<f32>(
        instance.model_row0,
        instance.model_row1,
        instance.model_row2,
        instance.model_row3
    );
    out.position = model * vec4<f32>(vertex.position, 1.0);
    out.color = vertex.color;
    return out;
}

@fragment
fn fs_main(input: VSOutput) -> @location(0) vec4<f32> {
    return vec4<f32>(input.color, 1.0);
}