I have a small problem which I suspect can be solved in an easy and

elegant way, and it is simply lack of sleep/stupidity preventing me

from finding it.

I have a number of line drawings comprised of cartesian points. I need

to project them onto a sphere (they are drawings of constellations, so

I need to project them onto an imaginary celestial sphere) and convert

the points into sphercal co-ordinates.

I *can* map the points to a sphere, that's no problem. But obviously,

when I do this they become distorted. What I want to do is find out

what the points should be to get an undistorted view - i.e the mapping

that will produce a projection so the points match the cartesian

version. Obviously, I realise this depends on the projection used etc,

but basically, a small amount of distortion is fine. I am sure there

must be a simple way to achieve this, but I can't seem to manage it.

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Nick Veitch