@group(0) @binding(0) var smplr: sampler;
@group(0) @binding(1) var txt: texture_2d<f32>;

struct Uniforms {
    time: f32,
    beat: f32,
    intensity: f32,
    aspect_ratio: f32,
    resolution: vec2<f32>,
};

@group(0) @binding(2) var<uniform> uniforms: Uniforms;

@vertex fn vs_main(@builtin(vertex_index) i: u32) -> @builtin(position) vec4<f32> {
    var pos = array<vec2<f32>, 3>(
        vec2<f32>(-1, -1),
        vec2<f32>(3, -1),
        vec2<f32>(-1, 3)
    );
    return vec4<f32>(pos[i], 0.0, 1.0);
}

@fragment fn fs_main(@builtin(position) p: vec4<f32>) -> @location(0) vec4<f32> {
    let uv = p.xy / uniforms.resolution;
    var col = textureSample(txt, smplr, uv);
    let thr = 0.5 + 0.3 * sin(uniforms.time);
    if (col.r < thr) {
        col.r = 1.0 - col.r;
    }
    if (col.g < thr) {
        col.g = 1.0 - col.g;
    }
    if (col.b < thr) {
        col.b = 1.0 - col.b;
    }
    return col;
}