uvRotate.glsl

// https://gist.github.com/raphaelameaume
vec2 uvRotate (vec2 baseUv, float angle, vec2 center) {
    vec2 uv = baseUv;
    uv -= center;

    mat2 m = mat2(cos(angle), -sin(angle), sin(angle), cos(angle));
    uv = m * uv;

    uv += center;

    return uv;
}