GL refers to OpenGL, which is called open graphics library. It is a cross-platform and open source 3D graphical programming interface. Using OpenGL, users can draw all kinds of complex graphics, including three-dimensional models, dynamic images, mathematical curves and special effects. The advantage of this technology lies in its high programmability, convenience and portability. In addition, OpenGL also provides a variety of development tools and libraries, which can easily develop various graphics applications.

GI refers to global illumination technology, which is used to achieve realistic rendering effect in computer graphics. Specifically, GI is a technology based on ray tracing algorithm, which is used to simulate the propagation and reflection of light in the scene. Through GI, developers can realize real ray tracing, so that all objects in the scene can correctly display their positions, sizes, shapes and light levels. The development of geographic information technology has greatly improved the authenticity and fidelity of computer graphics and brought new possibilities for various applications.

GL and GI are widely used technologies in computer graphics. Through OpenGL, developers can develop various graphic applications, such as 3D modeling, game development, virtual reality and so on. GI technology is mainly used to achieve realistic rendering effects, and is often used in movies, animations, games and other fields to provide more realistic effects for visual experience. In addition, the joint application of GL and GI is also an important means of some advanced graphics applications. These technologies have their unique application value and technical advantages when achieving more advanced effects in computer graphics.