Shadow Mapping and Transparent Quads

Posted by CiscoIPPhone on Game Development See other posts from Game Development or by CiscoIPPhone
Published on 2010-10-31T10:37:26Z Indexed on 2011/02/01 23:35 UTC
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Filed under:

shadows

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shadow-mapping

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depth-buffer

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transparency

Shadow mapping uses the depth buffer to calculate where shadows should be drawn.

My problem is that I'd like some semi transparent textured quads to cast shadows - for example billboarded trees. As the depth value will be set across all of the quad and not just the visible parts it will cast a quad shadow, which is not what I want.

How can I make my transparent quads cast correct shadows using shadow mapping?

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