ABSTRACT
One of the simplest libraries proving window creation and user interaction is a GLUT library. It is the cross-platform library written for OpenGL and in OpenGL style. Various OpenGL demos and examples have been written using GLUT – it is very small and easy to use. However, GLUT is not open-source. The glutInit command initializes the library itself and the glutInitDisplayMode command is used to specify various display properties for the windows that will be later created. Actually glutCreateWindow returns an integer window id which can be later used if we want to work with more than one window. Also this command makes the created window the active window so that the commands setting various callbacks set them for this window only. The GLEW library is an open-source cross-platform library allowing access to nearly all OpenGL extensions and also OpenGL 3 and OpenGL 4 commands.
