[comp.graphics] Z buffer data back to line segments

sundar@ai.mit.edu (Sundar Narasimhan) (03/28/91)

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.