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From: sundar@ai.mit.edu (Sundar Narasimhan)
Newsgroups: comp.graphics
Subject: Z buffer data back to line segments
Message-ID: <14419@life.ai.mit.edu>
Date: 28 Mar 91 12:50:11 GMT
Sender: news@ai.mit.edu
Reply-To: sundar@ai.mit.edu
Followup-To: comp.graphics
Organization: MIT Artificial Intelligence Laboratory
Lines: 13

Hi: I have a somewhat unusual problem. I'd like to go from Z-buffer
data back to line segments. I have a bunch of polygons that I render
using a spanning scan-line Z-buffer hidden surface algorithm. However,
for various reasons, I'd like to just display the edges. 

My hidden surface algorithm internally calls something like
display(window, ycoordinate, leftx, rightx, color);
to set the Z-buffer at a specific scanline from left_x to right_x 
coordinates with the specified color. I thought of modifying this 
to just set the leftmost and rightmost pixels to implement what I
want to do above, but this doesn't work for near horizontal edges. 

So is there a way of doing what I want? Thanks much in advance.