Open GL Graphic Primitives

A 3D scene is made up from 3D objects, which are defined by a set of triangles, a so called triangle mesh. Each triangle consists of 3 vertices with associated attributes defined by the actual rendering state. A series of vertices is started with the glBegin() command, whereas it is ended with the glEnd() command:

For example a series of 3 vertices that make up a red triangle consists of the following OpenGL commands:

Each glVertex command immediately sends a new point with the actual attributes to the rendering pipeline.