Triangle Strips (IFMETriangleStrip)

A triangle strip is a series of connected triangular faces. These faces are defined by three consecutive points in a point list. The first three vertices, denoted below by v₁, v₂, and v₃, define the first triangular face. A new triangle is formed by connecting the next point with its two immediate predecessors. That is, every additional point v_i defines a new triangular face with vertices v_i–2, v_i–1, and v_i.

For example, the second triangle is defined by v₂, v₃, v₄, the third by v₃, v₄, v₅, and so on. The following diagram illustrates a typical triangle strip.

The orientation of a triangle strip is determined by two factors:

• The orientation of the first triangle. For information on how vertex order affects surface normal and front/back surface determination, see Faces.

• The flipped flag stored on the triangle strip. If the flipped flag is false, the orientation of the entire strip is the orientation of the first triangle. If the flipped flag is true, the orientation of the entire strip is of that of the first triangle.

Triangle strips may store measures on their nodes.

Triangle strips may possess optional front or back appearances, and may be single or double sided.