油库火灾虚拟现实建模优化技术研究

摘要

油库火灾虚拟现实中,不仅涉及复杂场景建模,而且需要对由于燃烧不充分产生的大量烟雾进行模拟.如果采用传统的粒子系统或分形技术来模拟油库场景和烟雾,必然造成计算机显示负荷过重而无法满足虚拟现实实时性的要求.本文将油库火灾场景中的静态场景以视距、投影面积和地形粗糙度为依据来确定节点的细节层次,实现场景多分辨率建模.根据油料火灾烟雾扩散的视觉表现为灰度变化的特点,用动态纹理来模拟油罐火灾产生的大量烟雾,通过线性插值生成不同透明度纹理,并且保持始终视线与烟雾面正交,大大地降低了显示负荷,有效地解决了实时性与逼真度之间的矛盾,实现了油库火灾虚拟现实优化建模.%In the virtual reality of oil depot fire, not only complex scene modeling is necessary, but also large amounts of smoke simulation because of inadequate combustion.It cannot meet the virtual reality real-time requirements because of display overload if the traditional particle system or fractal technology is used to simulate the scene and smoke.In this article, the static fire scene of oil depot is simulated by multi-resolution modeling.The LOD(level of detail) of nodes is determined according to viewpoint distance, projected area and terrain roughness.The gray variety embodies the diffusion of oil fire smoke.So lots of dynamic texture pieces are used to simulate the large amounts of smoke of oil fires.Different transparent textures are generated by linear interpolation.The smoke plane is kept always orthogonal to the line of sight.The load of display is significantly reduced and the contradiction between real-timeness and fidelity is settled effectively.So optimal modeling is attained.