Triangle strip

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Diagram of four triangles, 1, 2, 3, and 4, with vertices A, B, C, D, E, and F.

A triangle strip is a series of connected triangles, sharing vertices, allowing for faster rendering for computer graphics. They are optimized on most graphics cards, making them the most efficient way of describing an object. After the first three coordinates for the first triangle in the strip, each new triangle only has one more vertex, sharing two of the vertices from the last triangle. This compactness also makes them faster to load into RAM, as well as requiring less disk space.

For four triangles, as seen in the diagram, without using triangle strips, they would have to be stored and interpreted as four separate triangles: ABC, BCD, CDE, DEF. However, using a triangle strip, it can be stored simply as ABCDEF.

Converting a general polygon mesh to a single long strip is generally not possible. In order to describe a complete object, one has to create either several strips, as used in Stripe,^[1] or a degenerate strip, which contain zero-area triangles that the processing software or hardware will discard. The degenerate triangles effectively introduce discontinuities or "jumps" to the strip. For example, the mesh in the diagram could also be represented as ABCDDFFEDC, which would be interpreted as triangles ABC BCD CDD DDF DFF FFE FED EDC (degenerate triangles marked with italics). Notice how this strip first builds two triangles from the left, then restarts and builds the remaining two from the right.

The use of polygon strips in products distributed in the United States prior to December 4, 2014, may be subject to a patent owned by General Electric Company.^[2]