WebGL: 3D application development - HTML5 in Action - page 417

3d drawing basics
The most confusing part of creating players is probably the shape() and color()
methods. The shape() method assembles the triangle in figure 9.10 , and the color()
method fills it in with white.
Figure 9.10. Diagram on the left shows a triangle comprising three points from the player's matrix data. The right
diagram shows a Cartesian coordinate system with x, y, and z.
The single form of the word vertices is vertex . In math, a vertex of an angle is an endpoint
where two line segments meet. Declaring three vertices, you created a triangle, as shown