Introduction to Maya - Modeling Fundamentals Vol 1
This course will look at the fundamentals of modeling in Maya with an emphasis on creating good topology. We'll look at what makes a good model in Maya and why objects are modeled in the way they are.
# 1 24-03-2004 , 08:23 PM
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Alpha Shadows

I have a plane in a scene textured with a texture containing an alpha channel (its basically an object on the middle of the plane, with a fully transparent area around it). I was told that any shadows the plane projects will take the alpha channel into account, but as it is the whole plane is projecting a shadow.

Is there something I'm supposed to do to get a shadow only from the non transparent areas of the texture?

# 2 25-03-2004 , 09:25 AM
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have you just got an alpha channel in your image or have you mapped it to the transparency channel? What I would do is get the texture's alpha channel and save it out to another file as a greyscale image. Then map that to the transparency texture channel. That will probably give yo ubetter results.

Let me know how you go.
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# 3 25-03-2004 , 04:46 PM
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Only raytracing works with alpha-maps so make sure your shadows are raytraced.


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# 4 25-03-2004 , 05:31 PM
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hmmm I tried it out with raytraced shadows just to see, but it didn't work. Without them, all you have is a shadow of your plane. With them, I can get no shadow at all. hmmm.....

edit*** bah... I see what I did. I just turned on raytraced shadows in the light attributes without turning on raytracing in render globals. =P

# 5 25-03-2004 , 10:39 PM
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Yeah i figured out that it only works with raytracing.

The problem is you can still see the outline of the plane in shadow. Ive read a tutorial that says you can fix this with shader networks (which I have no experience with). Is there any easier way?

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