Very cool, Kixum. What was the formula? That shape would make a fun alien or monster, flying toward you to absorb your soul! Well, if that's your idea of fun, anyhow. nyar1ath0tep, I'm not sure that x has to use u, and that y has to use v (I guess I need to test this more). Plus, I'm not sure how RDS differs. nivek, I think that your x definition might be ok, and that the problem is have both y and z equal to a constant; the result would be a line segment at y=1 and z=1, with the width determined by your x formula, which might not be visible, or might confuse RDS. Try making either y or z a function of u or v, like y=10u, and see if that helps. keithw, I like the "checkboard" you got. Would make for a challenging game, don't you think? I'm not sure, but I think you could make a checker board that "stuck" to the shape, by defining the regions in terms of u and v. You might try a simple 4-square, with something like: a = floor(u2); (result should be 0 or 1) b = floor(v2); (result should be 0 or 1) blue = ab; (result should be 0 or 1) I think the result would be a 4-square checker board, but you guys might want to check my math. Um, might have to add some sort of fudge factor for u and v = 1, but I'll test it when I get home today.