Painter's algorithm
  problem with simple depth-sorting: objects that cross the same Z plane
    BSP trees handle this
    some can be solved by more careful sorting; some require splitting
 
example of a cycle; no correct drawing order!

O(dxy), where d is the depth complexity at each point



use: whenever you lack a Z buffer, and have convenient access to a depth-ordered list.
coherence: object coherence
scene footprint: total
memory footprint: one object at a time
overdraw: total
preprocessing: creating the BSP tree or some other sorted list
clipping: not done
transparent object support: with A-buffer, sure.