Okay, here comes one that I haven't been able to figure out for the life of me.

I have a spaceship model, and I move it through my level. When it gets to within 100 quants of the outside of a planet model, I would like it to orbit the planet, left to right, facing slightly towards the planet. I would like it to continue orbitting the sphere and present a menu to the player, allowing key input or mouse clicks on the menu, until the "X" key is pressed. Once pressed, the menu should disappear, the ship should smoothly turn away from the planet, escape orbit by 50 quants, and return steering to the player.

Problems that I have had are that the spheres are different sizes, and everything that I do seems to focus on the origin of the sphere and not its perimeter. I either end up inside the planet model, or way too far away.

Might be too much, but hey, you asked!

Cheers
Mark