18 Oct
2004
18 Oct
'04
9:52 a.m.
On Mon, 2004-10-18 at 21:21 +0000, Ethan Dicks wrote:
Sure. It's a non-trivial exercise, for sure. Looking at images like
(warning, big file):
http://www.slc.k12.ut.us/staff/larmad/science/Images/Earth_from_space.jpg
I wonder if that many colours are needed - given the scale of the globe,
colour changes are very rapid. Maybe a base palette of 16 blues, greens
and browns would work, with a handful of duplicates fading to various
shades of grey (from black to white) to allow clouds and shadows. Do-
able within a 256 colour palette for a screensaver I would think anyway
- not sure if it'd require too many colours to have it as a background
to a desktop on an 8 bit display though.
Cloud algorithms are somewhat beyond me, however :-)
Aside: We just installed a 6 CPU HP T500 the other day which is crying
out for something visual on it to chew up serious CPU cycles :) I hung
an 8 bit xterm off it the other day; just need to get gcc on there and
then I can build some useful stuff (xfractint and POV seem like good
places to start)
cheers,
Jules
On Mon, Oct 18, 2004 at 06:32:17PM +0000, Jules
Richardson wrote:
Well let me know when it's done! We've got a few Unix systems at the
museum onto which I was going to put xearth anyway :)
On Mon, 2004-10-18 at 17:41 +0000, Ethan Dicks
wrote:
Naturally. I'm really big on Open/Shared Source. I've been hacking xearth recently to render
the Polar regions white.
Unfortunately, the shape tables are not commented, so I have to go
through manually to determine what shapes correspond to what land
features.
Now that's pretty cool. Will you be releasing it into the wider
world? :) I wonder if a
modern version is overdue that does do some pretty good
shading approximation of all the landmasses? And even better, some form
of chaotic cloud approximation to give it that real 'earth from space'
feel!
Hmm... I just did a trivial code tweak... the hardest thing I'm doing
is reviewing (and commenting!) hundreds of shape structures. 