The OpenGL drawing process consists of drawing graphic primitives. These are basic shapes such as points, lines, triangles, quadrilaterals and polygons. There are also special cases when you can use the OpenGL utility functions (GLUT) to draw more complex objects such as curves, spheres, NURBS curves, and so on. However, this chapter is oriented toward basic OpenGL operations. More information about this library can be found at https://www.opengl.org/resources/libraries/glut/.

Immediate mode drawing commands consist of the gl.Begin and gl.End blocks. Each of these blocks contain the element drawing specification. For instance, there's only one specification for drawing points, but there are three modes of drawing a set of lines. You can draw each line separately or you can connect them in a way that each line segment will connect to the previous segment.

This recipe will show you how to use each individual type of primitive in certain situations with visual...