Study On Real-time Lighting And Shadow In Oil Field Virtual Simulation System

With the development of virtual reality, graphics and hardware technology, real-time light and shadow effect in the virtual scene has become increasingly important. The effective use of light and shadow technology not only increases three dimension and immersion of virtual scene but also guarantees the system runs smoothly. This thesis mainly discusses the basic theory of the real-time lighting and shadow and the application of virtual simulation system in the oil field, introduces virtual reality, the light model and shadow generation algorithm more detailedly which are applied in oil field virtual simulation system according to the actual situation finally.In the thesis, the virtual reality and real-time lighting technologies have been introduced firstly, including virtual reality concepts, characteristics, key technology and the real-time display in virtual scene, as well as the effect and implementation method of the light and shadow; secondly it discusses light model algorithm, introduces the local reflection model and shading treatment technology in the local illumination, as well as the radiosity and ray tracing algorithm in the global illumination, and studies billboard, specular reflection and environment mapping algorithm. Later it analyses the related theories and concepts of the real-time shadow mapping, expatiates the hard shadow and its algorithm, including pseudo-shadow, planar shadow, scanline shadow, shadow map and shadow volume, as well as the soft shadow which are based on the description of the images and objects.In the final part of this thesis, after introducing the characteristics, architecture and the main function of the oil field virtual simulation system, it proposes the overall design thinking of the real-time lighting and shadow module and their position and role in the system, the design aim and the platform of software and hardware. In the real-time rendering stage, the afore-mentioned light and shadow is applied to the oil field virtual simulation system after contrasted, analyzed and improved. The billboard, specular reflection and environment mapping algorithm in the light of module technology are achieved, and the real-time shadow effect is impled with the shadow map and the shadow volume algorithm, finally, the algorithms have been optimized and improved.