Kit: additive blending

test.kit

abstract Color: Uint32 {
    rules {
        (${a: Color} + ${b: Color}) =>
            ((($a & 0xff0000) + ($b & 0xff0000)) & 0xff0000) +
            ((($a & 0xff00) + ($b & 0xff00)) & 0xff00) +
            ((($a & 0xff) + ($b & 0xff)) & 0xff) as Color;
    }
}

function main() {
    var red: Color = 0xff0000;
    var green: Color = 0x00ff00;
    var blue: Color = 0x0000ff;

    var combined: Color = green + blue + red;

    printf("%x\n", combined);
}