Re: Displaying 3-D in 2-D

        On the question of displaying a 3-D star map in 2-D:

        I remember National Geographic putting out some pretty nice looking
star maps and even galactic maps using a system similar to one somebody has
mentioned.  They had a large circle laid out on the paper, but tilted at an
angle so that it looked like a long ellipse, i.e. as if you were looking at
it from 45 degrees off of the Z-axis.  Then they had stars marked in space
by placing them above the right location on the circular reference grid,
and altitude marked by using a line running down to a spot on the circular
plane.

The neat thing about this was that you could see both some semblance of
real distance in space, since "high" stars were further up on the page, and
"low" stars were further down, and right was right and left was left; but
you could also see where they were on a 2-D view because the line running
down from the star marked a spot on the 2-D ellipse/circle.

Of course, while this made a neat visual presentation (IMHO), I wouldn't
have to write the code to display it like that.  Not that it would be so
incredibly nasty, just that I have this distaste for any trig/geometry that
involves more than two transforms.   And I'll bet dollars to plasma guns
that Nat'l Geo hired somebody outside their regular cartography department
to do it, too...


                                        DGH
                                        glad to be back on TML
                                        after an absence of many years

+-----+-----+-----+-----+===========^-++-^===========+-----+-----+-----+-----+
David Hall                              [email removed]
Political Science/Philosophy/           [email removed]
        Whatever Else They Let Me Take, hah!
[address removed]
"Wherever you go, there you are." -- Buckaroo Bonzai