Casting shadow from a light using a layer

[Jeremy Allen]

I’m not really sure what you mean by blocked, but I’ll throw in what I know about it..

make sure your wall and floor layers are 3d

make sure your floor layer is set to “accepts lights” and “accepts shadows”.

make sure your wall layer is set to “accepts lights” and “casts shadows”. If you don’t want to see the wall, and only want to see it’s shadow, select “only”.

make sure your light is set to “casts shadows”.

You can make those adjustments under Material Options for each layer.

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8core MacPro, 3.0 GHZ, 10GB RAM, OSX 10.5.2
DualCore G5 2.0 GHZ, 2GB RAM, OSX 10.4.11

AE7 on both for now.

[Eric Goldstein]

Hi Jeremy,

Thanks for getting back to me. I’ve done all the things you’ve mentioned. To try to clarify what I want to do:
I have a wall and a floor, both 3D layers. The light is set to cast shadows. The wall is set to cast shadows. The floor is set to accept shadows. The wall has a window cut in it. If you look at the window, you can see outside it.

I want to set a light outside the window and shine it through the window onto the floor so that the shape of the window is cast on the floor i.e. the floor would be dark, except for the rectangle of the window through which the light is passing.

I can do this in combustion, but when I try it in AE, the light is completely blocked by the wall even though there is an opening for the window.

Is there anyway to acomplish this in AE using a light and a shape on a layer to partially block light?

Thanks,

Eric

Eric Goldstein
Giraffe Film Company
Los Angeles
eric@giraffefilm.com

[Frank Thomas]

How did you make the window? I just tried what you are attempting and it worked fine. On your wall layer, use a mask set to subtract, as your window.

[Eric Goldstein]

Hi Frank,

I made my walls in Photoshop and did a lot of detailed work on pane dividers, transparency etc. The work isn’t something I can duplicate entirely with masks.

Because I can see through the windows created in Photoshop, I had hoped I would be able to shine a light through them without haveing to use masks.

Thanks,

Eric

Eric Goldstein
Giraffe Film Company
Los Angeles
eric@giraffefilm.com

[Frank Thomas]

What format are you exporting from Photoshop? Does the format support transparency (alpha channels)?

[Brian Lynn]

As far as I know the concepts in this tutorial still hold true:

https://library.creativecow.net/articles/gerard_rick/Projection_tut.php

There was another one that used a series of stained glass panels to create a neat projected image, but I can’t seem to find that one.

Good luck =)

[Eric Goldstein]

Hi Frank and Brian,

Thanks for your responses. I am using a photoshop file, which I am bringing into AE as a composition containing the various walls of the room I’m building. Photoshop files do, of course, support alphas, but I’m using transparency built into the walls. Could this be the problem?

AE’s lights are behaving as if there is no wall there.

Thanks Brian for the tutorial reference. I’ll take a look.

Eric

Eric Goldstein
Giraffe Film Company
Los Angeles
eric@giraffefilm.com

[Eric Goldstein]

Frank and Brian,

Thanks again for your help. I found the problem:

My wall was Precomped. I checked collapse layers and thought that the material choices I made to the precomp would act globally on the comped layers. But, apparently it doesn’t work that way.

Once I set the individual layers in the pre-comp to the correct settings, it worked perfectly.

Best,

Eric

Eric Goldstein
Giraffe Film Company
Los Angeles
eric@giraffefilm.com