近二十年來，在製作飛行模擬系統上已有重大的改進。與真實環境比較，一個模擬環境已經能夠提供接近真實的外觀與操控。然而就整個戰術飛行模擬系統而言，在低階個人電腦上做即時的大區域地形展示是一種嚴格的挑戰。
在本篇論文的研究中，我們提出以漸進式網格 (progressive meshes) 為基礎的動態載入式 (dynamic-loading) 視點相關 (view-dependent) 的多重解析度模塑 (multiresolution modeling) 技術來達真實飛行模擬環境的建立。漸進式網格表示法定義出一個任意地形的連續不同解析度模型序列。 然而建立這樣一個大型地塊的漸進式網格表示法是非常耗時間，而且載入這樣大量的資料到記憶體中再做處理，也是非常浪費資源的一種做法。因此，我們將大區域地形模型細分成小單位的地形區塊，每個區塊各自擁有不同解析度的變化，並且根據使用者的視點參數，動態載入所有相關的地塊做展示。此外，在戰略飛行模擬的應用上，我們建立一個控制介面和各種不同操控視窗來模擬戰機的飛行，使得使用者有操控真實戰機飛過地形的感覺。

Technical advances over the last 20 years have made flight simulation particularly effective. Compared to a real flight environment, simulation gives close control of the conditions under investigation, and allows specific flight situations, some of which are rare or hazardous, to be available on demand. However, the real-time rendering of large terrain models on a low-level personal computer is a challenge for flight simulation. In this paper, a multiresolution terrain modeling based on the progressive mesh (PM) with dynamic loading technique is proposed to achieve the purpose of flight simulation. The PM representation defines a continuous sequence of different-resolution approximate meshes for an arbitrary terrain model. However, it is very time consuming to construct a PM representation of a large terrain model; moreover, it is generally a waste of loading the whole terrain model into memory. Thus, we partition a large terrain model into blocks and then dynamically load the necessary terrain blocks into the memory for rendering. For the flight simulation system, we build a control interface and various flight windows to simulate the flight environment; let users feel as they are aviating a fighter over the terrain.

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