View Full Version : light coming through window..please help!

04 April 2006, 02:37 AM
First off...probally a really stupid question, but if I have a spotlight in Maya 7 outside the window, how do you make it so it only lights through the window rather then lighting the whole room. Next question, I also want a bit of light fog coming in through the windows and the door, how would I do this so it's not everywhere in the scene. I also tried to put a grid on the intensity of the spotlight so it would look more realistic shining through the bars on the window, but it's not working properally. It's only lighting the area I don't want lit rather then the other way around. I also was looking at some previous posts and I was wondering if you can use radiosity in Maya? Any help or any other input would be greatly appreciated

04 April 2006, 03:41 AM
Without mentalray or other render plugins,you will probably use not only one light too simulate the lighting coming through windows and then lit the whole room.Maybe a spot light outside room,couples of lights indoor.

If you are rendering with mr or other plugins,GI is the realistic solution.Maybe only one spot light outside is enough,maybe a little more,thats up 2 you.

04 April 2006, 10:40 AM
I had quite a bit of trouble getting MR to use the outdoor light to light the room. I don't know why. In the end I added a subtle mr Area light to give the GI something to work with.

As for the window; I don't know about Maya but in MAX I just make sure I've got some geometry outside the room - i.e. an outer wall enclosing the window frames - and make sure the spotlight is casting shadows. Then you'll just get light coming through where it can (the glass).

Hope this helps, sorry if I'm patronising you :P.


04 April 2006, 07:33 PM
There's a way to do it, let me see if I can come up with a tutorial real quick.

04 April 2006, 08:01 PM
Ok, here's a small tutorial on what do to. First, know that there are people who are lighting Geniuses, and that they have names like Jeremy Birn. I am not a lighting wiz, but I want to be one when I grow up. heh...

First realize what you are trying to do. Only then will you realize that you are not trying to re-create a spot light, you are trying recreate the sun. (the sun usually pours through windows, not spotlights)...

What does that mean for you? Well, generally you have a cone of light for spotlights and that it's not the most realistic thing when trying to make a sun's light, which is pretty much infinate in one direction.

So when I create light, I use a directional light. Look at the included image.

1. Create a directional light. Place directional light anywhere in the scene, but make sure the angle matches the angle that your light is going to pour through. So I usually put these guys high and aim down (low how the sun does!)

2. Go into the attribute editor for the light and click on the checkerboard button next to the Mcolor node. Your materials menu pops up

3. click on the mental ray tab at the top.
3.2 If you don't see mental ray show up, click on the render settings button and choose Mental Ray for your Renderer.
3.3 If you don't see the mental ray renderer, go to window -> settings/preferences -> plugin manager. Make sure Mayatomr.mll is loaded and preloaded. hit ok. go do 3.2 again

4. scroll down to the mental ray lights section and choose Mib_cie_d . This shader has the capability to recreate light the same why physics and color photographers think of. In the form of Kelvins. He created a scale based on his name to express how bright and the color of the light. A match flame about to die out is 1 kelvin for example. But a bright white light is upwards to 10000 kelvin.

5. In the attribute editor you will now see temerature and intensity for your settings. Plug a number from Jeremy birn's handy guide and how bright and color you want your light. The intensity usually can stay at 1, unless you think it's too bright or dark. That's your call.

Also make sure that your shadows are set up correctly. If you want help on that, just reply.

04 April 2006, 08:09 PM
Also keep in mind that this is just a start, but hopefully it'll give you an idea the amount of power mental ray offers for lighting

CGTalk Moderation
04 April 2006, 08:09 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.