Editing Painter's algorithm (section)

== Limitations ==
[[File:Painters problem.svg|thumb|Overlapping polygons can cause the algorithm to fail]]
The algorithm can fail in some cases, including cyclic overlap or piercing polygons.

=== Cyclical overlapping ===
In the case of cyclic overlap, as shown in the figure to the right, Polygons A, B, and C overlap each other in such a way that it is impossible to determine which polygon is above the others. In this case, the offending polygons must be cut to allow sorting.<ref name=":0" />

=== Piercing polygons ===
The case of piercing polygons arises when one polygon intersects another. Similar to cyclic overlap, this problem may be resolved by cutting the offending polygons.<ref name=":0" />

=== Efficiency ===
In basic implementations, the painter's algorithm can be inefficient. It forces the system to [[rendering (computer graphics)|render]] each point on every polygon in the visible set, even if that polygon is occluded in the finished scene. This means that, for detailed scenes, the painter's algorithm can overly tax the computer hardware.