# Qt OpenGL Classes

## Introduction

OpenGL is a standard API for rendering 3D graphics.

OpenGL only deals with 3D rendering and provides little or no support for GUI programming issues. The user interface for an OpenGL application must be created with another toolkit, such as Motif on the X platform, Microsoft Foundation Classes (MFC) under Windows -- or Qt on both platforms.

The Qt OpenGL Extension provides integration of OpenGL with Qt, making it very easy to use OpenGL rendering in a Qt application.

## The QGL Classes

The OpenGL support classes in Qt are:

- QGLWidget: An easy-to-use Qt widget for rendering OpenGL scenes.
- QGLContext: Encapsulates an OpenGL rendering context.
- QGLFormat: Specifies the display format of a rendering context.

Many applications need only the high-level QGLWidget class. The other QGL classes provide advanced features.