Treats each triplet of vertices as an independent triangle. Vertices 3n-2, 3n-1, and 3n define triangle n. N\3/ triangles are drawn.
Draws a connected group of triangles. One triangle is defined for each vertex presented after the first two vertices. For odd n, vertices n, n+1, and n+2 define triangle n. For even n, vertices n+1, n, and n+2 define triangle n. N-2 triangles are drawn.