Visible Surface Determination

The Z-Buffer sure made life easy

Hidden surface removal is about getting the correct pixel shown on screen when there are overlapping surfaces. Z-buffer is now the standard.

Binary space partitioning - 1980

By splitting the polygons along the planes of the polygons one can create a BSP tree that can provide a depth sort of all surfaces from any point. Slow process that is not run time friendly.

Z-Buffering - 1974

Painter's algorithm - 1972

Sort the surfaces on back to front order and then draw them.

Warnock algorithm - 1969

This algorithm split the view-port in four equal parts and check what polygons is in each area. If it is only a single polygon then it is draw. If it more polygons then it keeps splitting each area into four until there is a single polygon left or it is down to an area of a single pixel. If it reach a single pixel the polygon that is closest to the screen is drawn.

S-Buffer or Segmented-Buffer - 1999

Edge List

Back-face removal

Avoids drawing surfaces that face away from the camera as they can not be seen.