If you have vertices which are exactly the same (not just their positions, but all their attributes) you may be able to save memory bandwidth by sending only unique vertices, and assembling them into triangles by giving a list of 16-bit (or 8-bit) indices.

So in our quad example, we can give only the four corners, and get two triangles by giving six indices. Or we can draw circles (approximately) by creating a fan of triangles using a common center point for every triangle, and using a set of points around the circle twice (for the two triangles on each side).

<< [Solid Quad] [Index] [Global Variables] >>