Random.jack

class Random {
    // random seed
    static int seed;

    // generate seed when key pressed
    function void seed() {
        var int key;
        let key = 0;
        // increment seed until key pressed
        while(~key) {
            let seed = seed + 1;
            // loop around
            if (seed = 32767) {
                let seed = 0;
            }
            let key = Keyboard.keyPressed();
        }
        return;
    }

    // get a random number 0 to 32767
    function int rand() {
        let seed = seed + 20251;
        if (seed < 0) {
            let seed = seed - 32767 - 1;
        }
        return seed;
    }

    // get a number 0 to max
    function int randRange(int max) {
        var int mask, randValue;
        let mask = 1;
        while (mask < max) {
            let mask = mask * 2 + 1;
        }
        let randValue = Random.rand() & mask;
        while (randValue > max) {
            let randValue = Random.rand() & mask;
        }
        return randValue;
    }

    method void dispose() {
    	do Memory.deAlloc(this);
        return;
    }
}