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paul8262

OpenGL Game Dev's OpenGl book Question:

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paul8262    122
Can somebody please confirm,that the technique for shadows in the book is in fact"Planar Projected Shadows" and not worth using for realtime shadows? I made a previous post and somebody told me this technique is not worth it,and to go with Shadow Volumes. Someone else said go with "Standard Projected Shadows" but all the searching on the net iv''e done,brings up the same thing(which i think is Planar shadows). I don''t know the difference between the 2. Which technique does NEHE teach at his website? Is that standard Projected Shadows,or the same as in the book, Planar?(if it is planar in the book). I''m slightly confused about them. Also,if i was to go with Shadow Volumes(i have it working with Planes and a cube)what research do i need to do(what am i looking for)to be able to use vertices from a file(like in an ASCII milkshape 3D file)instead of vertices that are defined by code? A point in the direction,of what i need to research would be a great help. Thanks.

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mictian    138
yes, the gl book uses projected planar shadows like you said...the tutorial that is among NEHE''s collection explains shadow volumes.

shadow volumes require way more math and understanding...there are multiple articles on the subject at gamedev such as "optimized shadow stencil volumes" ( or something, the exact title escapes me )

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