   Gradient Sky rendering ideas
  Most of us have seen (and bookmarked) This Thread about how to render skys. I'm starting literally from the ground up trying to come up with my own implementation. Starting with a gradient from top to bottom going from blue to white(ish) for clear sky. Now the trick then becomes when the sun starts to get toward the horizon. There is some brilliant colors of red, orange ect but they fade off as a person turns from West (setting) to east. Not only that but the intensity (seems) to be around the sun at it sets and falls off from there (bight orange -> pinkish -> light blue -> dark). Now here is my idea ... having a skybox that has more verts (ie grid) all around the horizon. Having this me half as high as the original skybox (actual box) was. So we have a 4 sided quad grid facing toward the terrain. Think of it as a fence. Then we have 5 more quads (north, south, east, west and up) to cap it off. Now you would have to calculate a radial gradient as the sun approached the horizon in that 'fence grid'I think this, combined with a cloud plane, with a bit of light scattering (cg) would be a great effect. If I'm way off base please let me know. This is an interesting topic to me. [edited by - Jenison on February 15, 2004 12:45:59 PM][edited by - Jenison on February 15, 2004 12:48:51 PM]
  c''mon no one has anything ot say bad or good?;  Dont use a skybox, that just overcomplicates things... Use a sky dome instead.  Make its mesh fairly tesselated as you said and work with vertex colors for your gradient.  Use some pictures or something to find sky colors at various times of the day in different weather condidtions and make color maps to reflect this.  Then as time moves through your day, interpolate the colors from one sky color to another.  This would look pretty cool.  As for intensities near the sun, you could go as far as to produce the gradient dynamically radiating from the sun using exponential falloff. None of these ideas are new and all can be found reading other posts.  I hope this helps.  As for your cloud plane. You could use some simple images, or if do dynamic cloud generation which is VERY challeging.  I'm working on my own sky system that does this right now with not such great luck... it is **VERY** CPU intensive... for a few lame shoots of my test app go here.  If your interested in my work at all or want to share some ideas, my AIM s/n is samgzman.[edited by - samgzman on February 16, 2004 9:23:38 PM];  If you want to make a _really_ good-looking sky, check out the forum FAQ, it got a nice list of papers on sky gradients and cloud rendering.It can take quite a while to get a sky to look good and run at decent speed, I think I started my sky a little while after that famous thread was created and have been working on and off on it. Still got a problem with accuracy in the texture mapping (anybody know a fix if they know about this?). 