View Full Version : Alpha maps and z-buffer depth maps

03 March 2003, 04:59 AM
Geometry with alpha maps are not included in the depth channel?

Apart from tricky comping of alpha into depth map - does anyone know of a way to get these to render into the z-channel?


Toby W. Allen
03 March 2003, 11:00 AM
As far as I know, you enable the Z-buffer and save the images as a TGA (TARGA) and you should be able to get the alpha of the image.

Prolly not what you're lookign for though,

03 March 2003, 07:39 PM
I'm guessing your refering to transparency from a map on a model? No Z does not recognize transparency, only geometry. Thats why stuff like fur and paintfx has trouble with rendering behind transparent objects. Use a fake Z shader instead of the real thing. Then you get other benefits like antialiased Z.

03 March 2003, 10:24 PM

Actually, Zdepth maps can be rendered with transparency, just make sure you select furthest distance (facing normals to cam) and set the transparency treshold to 1.

This way you'll get transparency in your z buffer, and can make (for ex) transparent shadows with dmaps...


03 March 2003, 11:01 PM
Beaker - you're on the right track - I was hoping I wouldn't have to mess around with this, being an animator and not generally dealing with this stuff, it's a steep learning curve.

Is it a difficult process to convert all geom to the one shader?

(wishful thinking) anyone got a link to a mel that converts all shaders to grey etc....?

pixho - your method is intriguing yet vague! Care to shed a bit more light on this process.

thanks all for the replies.


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