Here is a picture of an old project I was working on. Its nothing
spectacular today, but it was pretty good at the time. I decided that I
should show it to the outside world even though it was obsolete before
completion (finished about 97).
I was developing a technique to display heightmapped quads without a
z-buffer. If optimized correctly, I could have made it just as fast as my
ordinary textured polygon renderer.
The procedure goes something like this -
I divide the cube along its quadrants (sections sliced perpendicular to x
and y axis). There are four different quadrants that parts of the cube
could be in. This is important for the drawing order. The top left is
draw from left to right top to down, etc.
I computed how often to sample the texture and heightmap based on the
number of pixels for each side. It is sampled in a regular rectangular
array( not scanlines, I tried those and it causes visual anomalies) This is
a step that can save time. The polygon can be sampled every five
pixels, and each of the resulting points can be connected. These can be
filled with a single color. In this way, heightmap complexity can be
traded for texture complexity using a consistent amount of time.