Virtual reality is an important direction of simulation technology is the simulation technology and computer graphics Human Interface Technology multimedia technology sensor technology network technology and other technologies is a collection of cutting-edge cross-cutting technology frontier disciplines and research areas. Virtual Reality (VR) mainly includes simulation environment, perception, natural skills and sensing devices. The simulation environment is a computer-generated, real-time, dynamic, three-dimensional, realistic image. Perception means that the ideal VR should have the perception of everyone. In addition to the visual perceptions generated by computer graphics technology, there are also perceptions of hearing, touch, force, movement, and even smell and taste, also known as multi-perception. Natural skills refers to the human head rotation, eyes, gestures, or other human behavior movements, the computer to deal with the participants' actions to adapt to the data, and the user's input to make real-time response, and were fed back to the user's facial features . Sensing device refers to the three-dimensional interactive device.
The history of the evolution of virtual reality technology can be divided into four phases: the first stage of virtual reality thought (before 1963); the emergence of virtual reality as the second stage (1963 -1972) concept of virtual reality And theory initially formed as the third stage (1973-1989) virtual reality theory further improved and applied as the fourth stage (1990-2004).
Virtual reality is a combination of a variety of technologies, including real-time three-dimensional computer graphics technology, wide-angle (wide field of view) stereoscopic display technology, tracking technology for the viewer's head, eyes and hands, and haptic / force feedback, stereo, Input and output technologies. The following is a description of each of these technologies.
Real-time 3D computer graphics
In contrast, the use of computer models to produce graphic images is not too difficult. If we have a sufficiently accurate model and we have enough time, we can generate accurate images of various objects under different lighting conditions, but the key here is real-time. For example, flight simulation system, the image refresh is very important, while the image quality requirements are high, coupled with a very complex virtual environment, the problem becomes quite difficult.