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NanoGator
12-03-2003, 05:51 PM
Hi All,

I have a bunch of flickery lights I'd liike to animate. I saw "textured channel' and though "ooo I can just make a pretty image, then rotate it around a null or something, and textured channel will take care of everything!". Well, it does and it doesn't. It appears to read the image and build a motion curve from it, as opposed to saying "Where am I in X/Y/Z space, and where is that in relation to the image?"

Is there a way to do that? The effect would be like having a multi-colored gel over the light. So when it moves around, depending on where on the image it is, it changes color. Is that possible?

BAROBA
12-03-2003, 07:10 PM
I understand what you mean
There was this tutorial with a downloadable scene.
It had something to do with projecting a image and the colors changed too.
I thought the scene contained a room lit by a television set, and the arealight was the tv.
The technique involved the 3 colorchannels and 3 different textures, becuase the channels only read greyscale images.
But I cant remember what exact had been done to the channels.
It has been posted here, that is for sure.
Maybe someone else remembers the setup? Or maybe the maker recognices his scene :)
I will search again for it.

Triple G
12-03-2003, 08:55 PM
I'm pretty sure it was CourtJester who posted about the technique you're describing, Baroba.

aurora
12-03-2003, 09:30 PM
Heres the link to CourtJesters tut Triple G mentioned. I'm not entirely sure this is what you are after but I think that it will give you what you need to figure out how to do what you want. Good Luck.
http://www.altyna.com/lw/specrefl.htm

SplineGod
12-03-2003, 10:30 PM
Originally posted by NanoGator
Hi All,

I have a bunch of flickery lights I'd liike to animate. I saw "textured channel' and though "ooo I can just make a pretty image, then rotate it around a null or something, and textured channel will take care of everything!". Well, it does and it doesn't. It appears to read the image and build a motion curve from it, as opposed to saying "Where am I in X/Y/Z space, and where is that in relation to the image?"

Is there a way to do that? The effect would be like having a multi-colored gel over the light. So when it moves around, depending on where on the image it is, it changes color. Is that possible?
Do they have to be lights or can you use something like single point polys with glow?

NanoGator
12-03-2003, 10:47 PM
Hey guys, thanks for the responses. Aurora, that tut isn't exactly what I was hoping for, but it provides an excellent fallback plan. Thank you!

Splinegod: I apologize, I should have described the result I was after. See my project here (http://www.cgtalk.com/showthread.php?s=&postid=995920#post995920)? I've got this cannon that will fire a particle beam. It generates the particles via the spinny things in the back. Because of this, I'd like to have little pops and flashes (lens flares plus light interaction). It'd be nice to be able to time them so that they more or less flash in a circular sequence.

I misunderstood what Texture Channel does. I thought you could apply an image like a texture in the scene, and when the light moves around it, it'll change intensity as it moves. So I thought I could make a noisy texture, then have it spin along the z-axis. The lights would automatically pop and flash at the right time. If I spin the texture faster, it flashes even faster. Etc. The plugin doesn't do it that way, but if it did my solution would be reaally easy to implement!

Well, now ya kinda know what I'm after. I'm 100% open to any and all suggestions. Limitations breed creativity. :)

kretin
12-04-2003, 12:36 AM
You could try applying a blank projection image to the light, then use Textured Filter (in Image Editor) to apply either procedural, gradient or another texture to it, giving you control over size, motion and/or rotation of the texture that's applied to the projection image. Doing this with World coords might let you simulate the technique you'd like to use.

NanoGator
12-04-2003, 12:40 AM
Would that affect the color of the lens flare?

kretin
12-04-2003, 12:49 AM
um, oh yeah.... not so much :p

Ok, I'd go for CourtJester's technique then :)

Using his technique, if you set the textures being used to world coords you should still be able to move the lights around a still texture, or give the texture a reference item and you could animate the pos/rot of the texture...

LFGabel
12-04-2003, 05:45 AM
Or might be easier to do this kind of effect in post...?

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