_dodger opened this issue on Dec 01, 2002 ยท 28 posts
_dodger posted Sun, 01 December 2002 at 1:34 PM
_dodger posted Sun, 01 December 2002 at 1:35 PM
_dodger posted Sun, 01 December 2002 at 1:36 PM
_dodger posted Sun, 01 December 2002 at 1:37 PM
_dodger posted Sun, 01 December 2002 at 1:38 PM
_dodger posted Sun, 01 December 2002 at 2:08 PM
Is it documented anywher ethat as you increase the Angle End of a spotLight, the shadow cast by it decreases in sharpness? It appears that somewhere between 140 and 150, the shadows cast and the outer perimetre of the light's area of effect begin to bleed into one another to the point where you can no longer see the cast shadow, and the overall effect of the light is merely dimmed. Crap crap crap. That means it's going to take more than 4 lights to make an omnidirectional. I was hoping an equalateral pyuramid would do the trick. But there needs to be about ten degrees of overlap, and while a d4 shape will provide 120-degree ranges, for that overlap there needs to be a 140-degree angle, which means that at that point the shadows fuzz out.
lesbentley posted Sun, 01 December 2002 at 4:01 PM
Very interesting. Thanks for the info.
lesbentley posted Sun, 01 December 2002 at 5:06 PM
lesbentley posted Sun, 01 December 2002 at 5:13 PM
_dodger posted Sun, 01 December 2002 at 6:15 PM
_dodger posted Sun, 01 December 2002 at 6:16 PM
lesbentley posted Sun, 01 December 2002 at 7:09 PM
lesbentley posted Sun, 01 December 2002 at 8:52 PM
lesbentley posted Sun, 01 December 2002 at 8:56 PM
lesbentley posted Sun, 01 December 2002 at 9:48 PM
lesbentley posted Sun, 01 December 2002 at 9:53 PM
lesbentley posted Sun, 01 December 2002 at 10:04 PM
_dodger posted Sun, 01 December 2002 at 11:08 PM
lesbentley posted Mon, 02 December 2002 at 12:07 AM
I did rotate the second set, and pushed the Angle End to 100, that last was not the most flattering, but it demonstrated the problem better. I still don't think that 8 is enough, but I hope I'm proved wrong. 18 is a lot so perhaps there is a happy median. Any way for the moment I plan to push on with 18 light set and try to make the ERC a bit more user friendly before I put it up in the freebies.
_dodger posted Mon, 02 December 2002 at 1:17 AM
From what I can see, the angle of a spotlight seems to be 60 degrees no matter what. I'm not entirely sure what the attenuation parametres are based on. Based on this I've built a 14-pointed arrangement of them where they are placed at the vertices of a dodecahedron (20-sided pythagorean solid). This completely minimises the overlap which, despite the numbers given for the angles, don't seem to have anything to do with the actual angle of the cast light. Why? Because at 160 degrees (the default angle limit), almost half a sphere would be lit -- but isn't. Further, it would make sense that if the angle really described the angle of the light, then upping the limit to 360 and setting it there would then create almost a real omni. But that hasn't worked at all.
_dodger posted Mon, 02 December 2002 at 1:18 AM
_dodger posted Mon, 02 December 2002 at 1:20 AM
lesbentley posted Mon, 02 December 2002 at 4:00 AM
It's looking good dodger, thanks for sharing. You worked out the angles for positioning on a dodecahedron, wow, I cant even work out how to stand up straight (perhaps its the Vodka). Unfortunately Im at college for the next 7 hours, so I wont be able to play with it for a while, the light set that is ;).
Little_Dragon posted Mon, 02 December 2002 at 8:58 PM
_dodger, I don't know if you ever saw this, but I conducted a similar experiment in omnidirectional lighting earlier this year.
http://www.renderosity.com/messages.ez?Form.ShowMessage=680431#8
I needed omnis, or at least something close to omnidirectional, in order to simulate naked lightbulbs. I went a bit overboard with the spotlights (especially since I only had 128MB of memory), but basically the technique was the same.
I've since changed hosts, so here's a new link to the video:
Video clip (MPEG format, 1.37MB)
I hope that DAZ Studio and future versions of Poser will feature omnis, because interior lighting is a pain-in-the-tail without them.
_dodger posted Mon, 02 December 2002 at 10:56 PM
Here's a scene rendered with the omni parented to a prop that's parented to the flame. I'm still getting weird results trying to parent a light or another figure by a gravity-affected part. Thus the prop in-between.
_dodger posted Mon, 02 December 2002 at 11:07 PM
kawecki posted Tue, 03 December 2002 at 9:46 AM
Poser spots with angles greater than 90 has strange behaviour, you can have ufo lights (light pass through a wall that cast shadows),etc, etc, etc
Stupidity also evolves!
lesbentley posted Wed, 04 December 2002 at 4:38 PM
Attached Link: OmniLight
I've posted an ERC controlled OmniLight in the free stuff. It's far from perfect, but at least it's a start, and perhaps others will get inspiration to develop the ideas further.