Drift

import { dot } from "@drift/math";

shader Grayscale {
    props {
        texture: sampler2d;
    }

    fragment (uv: vec2) -> color {
        const weights: vec3 = vec3(0.299, 0.587, 0.114);

        let sample = texture.sample(uv);
        let gray = dot(sample.rgb, weights);
        return color(gray, gray, gray, sample.a);
    }
}