View Full Version : lighting up a christmas light!! help

11 November 2005, 06:38 AM
I modeled a christmas light and i want to make it light up but im having trouble with this anyone know how to do this iv searched far and wide i dont know if my search skills suck but what ever anyone have any idea how to do this here is my renderd image

please look
i just want these guys to light up and look real please help thank you

11 November 2005, 08:59 PM
If you use a Architectural Material for the color part of your little lights you can specify a Luminance value (you may need to play with this value). Then you can check off the box for "Emit Engery based on Luminance" in the "Advanced Lighting Override" box in this material.

Then render using Radiosity. If you check off "Render Direct Illumination" under the Redering parameters in Advanced Lighting Dialog you don't need to process the mesh.

For a added touch give this mat a matid of 1 and use a comination of lens affects like star and glow to get the glare on your lights.

this is how I do lighting for night scenes with traffic lights and what not

Good luck.

*Edit* If you do go with the emit energy option you will need to process your mesh *edit*

11 November 2005, 10:00 PM
thanx man for the info i will deff try and get on this im using brazil to render this im not sure if that makes any difference but i will give this a shot and post my results

11 November 2005, 11:17 PM
My $.02

Using radiosity for something like that is really only going to be feasible if you have a very simple scene, like what you posted. If you plan on having a scene with hundreds of these lights in a strand, the time it'll take to calculate a radiosity solution from that will just be ridiculous.
Personally, I'd just suggest placing an omni light in the center of your light shape - maybe two, if you need a more accurate form. Adjust the lights (especially their falloff settings), and if you need shadows be sure uncheck shadow casting for your light object. I'd also model the filaments of the bulbs (as splines), and give them a self-illuminating material. I'd probably create a sphere around the filament as well, to composite out a layer to use for applying a glow in post.
My main suggestion is to just try and keep it simple. You can get great results with a simple setup if you tweak everything correctly. If you're going to be doing an extreme close-up of the bulbs, then sure, give the bulb full raytraced reflections, throw in a GI or radiosity solution from the filament, add in some IBL and just go nuts with the rendering settings. But if you're going to use it for anything else, most of that is going to be unusable, and a waste of time really.

11 November 2005, 03:00 AM
yeah i tried to do it with a omni light it didnt work to well and im unsure how to do a self-iluminated material im using brazil, in final render its simple but brazil is diff...

thank you for the advice :)

i just want it to light up like this

11 November 2005, 01:55 PM
This is what I got using the method I described above. It was done very quickly, but you can see the potential if I put more effort towards it.

11 November 2005, 06:58 PM
nice, i will give that a shot

11 November 2005, 09:12 PM
This is what I got using the method I described above. It was done very quickly, but you can see the potential if I put more effort towards it.

Personally, I'd use Particle Flow and a Material Dynamic

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11 November 2005, 09:12 PM
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