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Bahamut5098
10-08-2008, 06:57 PM
Hey, let's say I have a box with opacity set to 50. I put an omni light in the center of the box, but when I render it, the light does not show through the box; it just lights the plane underneath the box.

How can I have it to where the light's source seems to be coming (or shining) from within the box?

UnixMonkey
10-08-2008, 07:25 PM
There are several was to get that effect, but the easiest way, depending on your software, is to tell the light to exclude the the geometry of the box from it's illumination list. Sometimes you have to employ two lights at the same position to get the desired result. For instance if you want the light to look like it's illuminating the material of the box while a little light transmits through the material: Create two lights at the same position then set one light to exclude the box's geometry and also set that light's intensity lower and its color similar to that of the box's material. One light illuminates the box, while the second light appears to pick up the color of the box and illuminate the objects outside the box.

This is only one way to achieve this result. I tend to like it as it has minimal effect on rendering times, but there are plenty of other ways of doing it.

Richard

Bahamut5098
10-08-2008, 07:51 PM
I'm using 3DS Max 9. How do you set a light to exclude the boxes geometry?

Baothebuff
10-08-2008, 11:35 PM
are you saying you want the box to glow? or to have light rays coming out of it. Either way, it not a matter of simply putting a light in a box. Lights don't affect objects the way they do in real life. You got to do some tricks.

Bahamut5098
10-09-2008, 01:27 AM
I want the light to shine through the object, to appear like it's coming from within the box(or lightbulb)... Any suggestions?

Baothebuff
10-09-2008, 02:52 AM
Since a light in 3d is not actually an object, you have to create something to fake the actual bulb. So very simply, it would be a glowing sphere so create a sphere and assign a standard material to it. make the color white and turn the self illumination to 100. So, when you render, the sphere will be completely white and it will look like the light is coming from that.

Hopefully that's what you're looking for.

Bahamut5098
10-09-2008, 06:54 AM
No offense, but that's a little lame. I want light rays to be coming from within the sphere outward..so people believe that there is a light in the sphere itself.

UnixMonkey
10-09-2008, 05:29 PM
In Max, either create a new light or go to the modify tab with an existing light and look at the "General Parameters" section. Just below the "Shadows" parameters you should see a button named "Exclude...". Click that button. A dialog box will appear that allows you to select the name of the geometry that corresponds to your sphere or box you want the light to pass through. Double click on the name of the geometry to add it to the list. You will notice in this dialog you can exclude illumination or shadow casting or both.

Richard

johnnymoha
10-09-2008, 06:56 PM
No offense, but that's a little lame. I want light rays to be coming from within the sphere outward..so people believe that there is a light in the sphere itself.

That's the technique that I was thinking about suggesting also, but I said to myseld exactly what you said ^ before I posted. :) Are you looking for something similar to the way a filament inside a lighbulb would look if the bulb where clear. I.e. Light from inside a surface, not the surface itself. shines through it and picks up some of the color of the object as well?

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