Volumetric light through stained glass

[soledo]

I have created a round window filled with small pieces of colored glass, similar to stained glass in a church. I'd like to put a light behind that window, so that there will fall colored rays through it.
I have tried to do that, but so far I have got only grey rays instead of colored ones.

I used the next settings:
- 1 polygon for the window, textured with jpeg of stained glass
- for that texture: transparency 40%; translucency 30%
- 1 point light behind the window, volumetric lighting enabled
- render options: ray trace enabled

Can anyone tell me why I don't see any color-rays?
Thanks!

[jeremyhardin]

is your polygon double sided? (cant remember if this matters, but it might)

and do you have ray trace transparency on?

[Baloney Pony]

Originally posted by soledo
I have created a round window filled with small pieces of colored glass, similar to stained glass in a church. I'd like to put a light behind that window, so that there will fall colored rays through it.
I have tried to do that, but so far I have got only grey rays instead of colored ones.

I used the next settings:
- 1 polygon for the window, textured with jpeg of stained glass
- for that texture: transparency 40%; translucency 30%
- 1 point light behind the window, volumetric lighting enabled
- render options: ray trace enabled

Can anyone tell me why I don't see any color-rays?
Thanks!

The fastest and easiest way to solve this problem is to take the light that is behind the window and make it a spot light. Look through the light while positioning it so you make sure you align it with the window.

You can then project an image through the spotlight - thus "cheating" the effect.

Using a point light to cast the ray is very ineffecient because a point light casts rays in all direction and LW must take the time to compute the rays. If you use a spot light then you are restricting the calculations and speeding up your render times.

If the projected map technique does not work for you, consider making each of the different colored glass pieces a different surface and add more geometry. I understand that this will require more work on your end, but in the long run it will pay off. You will not need to project an image with this technique. Make sure to to adjust the color highlights and color filter settings on the glass surfaces.

Hope thi shelps - let me know if you need more help.

-Da Pony

[Avebeno]

I just tried a glass window test. I had white light streaming through until I set my "Color Filter" setting up to 100% in the advanced tab in the surface editor.
If that still doesn't work try making the surface double sided if they aren't already.

[soledo]

I have made the texture double sided, and have enabled the color filter setting. I'm happy with the result; the light rays are indeed colored now.
I have attached a draft of my image, so that you can see the result.
Thank you for your help!

[lone]

nice work - how big is the picture, and how long did it take to render?

[Avebeno]

Looks great! I'm glad it worked!

- Ben