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aus79er
04-09-2002, 07:29 PM
Hi,
I don't know in detail what z-buffer means.
I think its used for hidden surface removal.
But i don't want it for that purpose.I want understand since it is used in CAM applications also.

I have searched few websites but not much information is available.
Can any body suggest me a good website or a book which explains Z-buffer in details.
Apart from books and website ,in general Explaination will also be fine...


Thanks,
aus

zed
04-09-2002, 08:51 PM
u could do a lot worse than http://www.amazon.com/exec/obidos/ASIN/0...6986651-9823315 (http://www.amazon.com/exec/obidos/ASIN/0201848406/qid=1018417755/sr=8-1/ref=sr_8_71_1/102-6986651-9823315)
the definitive computer graphics book
well worth the money, it explains practically everything to do with computer graphics

Jambolo
04-11-2002, 06:43 PM
Z-buffer is easy to explain. Here is a simple version of the usual operation of the Z-buffer.
For every pixel in the frame-buffer, there is a spot in the Z-buffer. Whenever an object is drawn into the frame-buffer, the distance from the camera to the object being drawn is stored in the Z-buffer for each pixel that is drawn.
When a pixel is about to be written, the value in the Z-buffer is checked first. If the object about to be drawn is closer than the pixel currently in the frame-buffer, the pixel is overwritten.
So you will never see an object that is hidden behind another object. If the farther object is drawn first, it will be overwritten by the closer object. If the closer object is drawn first, the farther object will not be drawn because of the Z-buffer check.

One thing that should be made clearer is that the Z test is done on a pixel to pixel basis.