【作者】 黄莹莹；

【导师】 郝燕玲；

【作者基本信息】 哈尔滨工程大学 ， 控制理论与控制工程， 2004， 硕士

【摘要】 本文以哈尔滨工程大学校园环境为虚拟空间，研究了基于多边形的虚拟现实漫游相关算法及应用。虚拟漫游是虚拟现实应用的一种，它通过实时的交互，使得用户能够自由观察和体验虚拟环境，其应用范围包括军事作战模拟，建筑设计规划，教学培训等领域。 文中首先讨论了复杂三维场景实时绘制问题，实现了复杂三维场景实时建模，冗余数据删减、纹理映射、多级LOD模型等场景复杂度的消减策略。给出了室内外结合的系统优化的场景数据库层次结构。其次，研究了虚拟漫游中人机交互控制及虚拟实体操纵技术。给出漫游中自定义的运动模型，手动漫游与自动漫游的切换，以及基于视线的碰撞检测算法和基于标准二维输入设备的虚拟实体选择方法，并实现了对受限运动实体的操纵。 本文着重论述了基于多边形的虚拟漫游算法。该算法的主要任务是提高计算机效率和显示质量。本文从这一目的出发主要研究了八叉空间刨分算法的实现。大大降低了内存的使用需求，增加场景复杂物体的数量和细节程度。 本文实现了虚拟校园漫游实例。实例使用自行开发的三维图像漫游引擎完成。引擎框架中定义了多种控制状态机制，增强了人机交互功能和虚拟漫游的沉浸感。更多还原

【Abstract】 Based on the campus of HEU as a virtual space, The algorithms of polygon-based virtual walkthrough and application are discussed in this paper. Virtual walkthrough is a kind of virtual reality technology, which enables users to view and experience the virtual environment freely. It is widely used in battle simulations, architecture designs, teachings, trainings and so on.In this paper, firstly, major efforts have been focused on discussing the real-time rendering of a complicated 3D scene. A series of complicated 3D scene modeling and simplification strategies on redundant data, texture mapping, multi-level LOD models have been realized. A database hierarchical structure of a scene combined indoors with outdoors and optimized method in walkthrough system have been provided. Secondly, human-computer interactive capabilities and manipulation of restricted moving entity have .been studied. Gived self-defined moving method and the changes of the walkthrough mode between hand control and auto control. In addition, collision detection and response approaches based on line of sight and picking approaches of virtual entity based on standard 2D input equipment have been offered, and manipulation of restricted moving entity has been realized.The algorithms of polygon-based virtual walkthrough are the more important parts of this paper. The basic tasks of such algorithms are to reduce the computing time and improve the quality of rendering at the same time. This paper presents an efficient implementation of OSP (octree based space partitioning) algorithm. Such algorithm improved computingefficiency and reduced memory needs. The number of complicated entities and the texture details in the virtual scene are greatly increased.A virtual campus walkthrough is implemented based on these algorithms. Such system used self-defined 3D walkthough engine frame work. Many control options are set in this 3D walkthough engine frame work. This improved human-computer interactive capabilities and immersion sense.更多还原