Alpha map and shadows

[Imperitor]

I made a net in one of my projects. I used an alpha map to do it, but when i put lighting in the whole plain casts a shadow. Can anyone help me?

http://img128.imageshack.us/img128/5484/00013hy.jpg

As you can see the light gets blocked even where the alpha is 0.

the netting looks bad because this was just a test.

[Spin]

Sounds like you need this tutorial. Small and easy to follow...
http://free.hostdepartment.com/B/Blender3D/grill/



A grill with a transparent shadow.

:)

[Imperitor]

Thank you. all I had to do was hit the TransShadows button :)

[migero]

how can i do the same with buf shadows ?

[RamboBaby]

You can't. Buffer shadows are created from an object's depth buffer as seen from the lamp's point of view which is causing the shadow to be cast in the first place. Geometry is the only property of the object that is taken into account.

[AndyD]

You can cheat by using a stencil texture on the lamp and setting the lamp to Square (easier) and Negative.

[ericsh6]

What I do is put all alpha mapped planes such as trees, bushes, etc., in one layer and use ray trace lights to illumante them (click the "layer" button on the lamp and make sure it is in the same layer as the alpha mapped planes). Every thing else can be buffer shadowed if you wish in a different layer. Render times are quick and you can put lots of alpha mapped trees this way.