在虛擬環境中，我們可以模擬真實或構想的環境；其中我們可以透過3D MAX、MAYA...等等的模塑軟體來構建3D模型，再以數學、物理、資料結構等技術來呈現虛擬環境中，逼真的運動行為及視覺效果。本論文的研究目的是在虛擬環境的導覽過程中，發展有效的碰撞偵測，並針對不同物體的屬性，模擬各種特有的碰撞反應。這些反應包括：火、煙、爆炸等視覺效果。從碰撞物體的屬性推論出碰撞後的視覺效果是很難的題目，且資料不充分，所以在本論文中，我們謹以煙的視覺效果為範圍去達此一雛型的建構方式。 The 3D visualization is a key component of a virtual-reality application system. There are many techniques influencing the performance and reality of the 3D visualization, such as, collision detection, visual effects, physical modeling, etc. In this study, we develop techniques of collision detection and visual effects for applications in a virtual environment. The collision detection emphasizes simulating the walking behaviors of human in a virtual environment, such as, walking, going up/down hill, going up/down stairs, etc. The visual effects are emphasized resulting from the attributes of collided objects, not just from the behavior of a collision of two objects. In the practices of visual effects, we first design data structures of attributes to describe properties of objects. Second, we use constrained physical formulas to deduce the parameters for a specific visual effect from the attributes of collided objects. At last, we implement a particle system to manage all visual effects in a virtual environment. In the second and third stages, we construct a “FXEditor” system to edit the visual effects and to render the simulating effects for helping the generation of visual effects.
