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Based on the 3D visualization information extracted for the Qucik Bird high-resolution satellite stereo images, combined the VC++6.0 platform and DirectX SDK, the 3D landscape of the area was built. For the landscape constructed based on the satellite image, it has a large data quantity. Using the visibility culling", "LOD algorithm and Mipmap to optimize the DEM and texture, the system running speed was improved and the fluently interactive operation was implemented. [ABSTRACT FROM PUBLISHER]

Level of detail (LoD) techniques provide efficient and established tools that reduce 3D models complexity while attempting to preserve their features. While these techniques are well documented and have been applied with proven results, only few solutions attempted to create a solution that is compatible with Motion Picture Experts Group (MPEG-4) facial animation standard, which involves human facial mesh simplification. In this paper we present our work on an adaptive LoD algorithm which prioritises the human face features in the facial mesh and simplifies the animation streams, reducing animation complexity and overhead. Our approach applies continuous LOD to a MPEG-4 compliant model using an extension of Garland's Quadric-Based Surface algorithm and introducing a novel error metric. This is achieved with a novel approach that applies a selective model simplification that is both MPEG-4 compatible and also can simplify animation streams. [ABSTRACT FROM PUBLISHER]

The current development platform or tools for virtual reality usually has some limitations, to address this issue, this paper presents a self-developed open-system walkthrough engine for the virtual environment. After the functional requirements analysis, it proposes the architecture and implementation process of the engine, and details the key technologies: model-loading technology, self defining script and LOD. The implementation takes Visual C++ as platform and DirectX as graphical rendering API. This engine has been tested and applied to the virtual indoor environment, the test results show that the engine is easy, stable and runs smoothly, which meets the expected demand. [ABSTRACT FROM PUBLISHER]

We propose a spatial partitioning level of detail (LOD) model and its application to material removal simulation of multi-axis NC milling. In order to reduce the number of voxel in the spatial partitioning model during NC milling simulation, octree split-level is given as the level of detail control strategy to generate different simple versions of simulated work piece model. Level of detail is selected according to the level of CNC hardware and resolution. For accelerating simulation the swept volume of cutter is described by implicit and coordinate transformation. We determine the spatial position relationship between cutter implicit and octant to clip octant color and recursively decompose the space of work piece which is the bounding box of cutter. Boolean subtract operation is implemented by comparing the octant color related with work piece and cutter. This method enables reducing the number of voxel, and fast simulation. Finally a example of five-axis machining verifies the effectiveness. [ABSTRACT FROM PUBLISHER]

LOD model based on quad-trees is improved on the basis of former researches. This model is applied to manage and organize terrain data. Node judgment rule is established to determine the detail degree of the present visual area. A new bidirectional way was given to recover the cracks according to distance. By programming, this method is proved to be able to generate multi-resolution terrain model continuously, improve the efficiency of terrain navigation, and realize smooth transition of the models with different resolution. [ABSTRACT FROM PUBLISHER]

Level of detail (LoD) techniques provide efficient and established tools to represent 3D models, while these are well documented and applied with proven results there is not much research and proven results that offer a solution that is both compatible with MPEG-4 (Motion Picture Experts Group) facial animation standard, and which considers a human face mesh simplification. In this paper we present our work on an adaptive LoD algorithm and attempt to preserve the human face features and simplify animation streams when possible by analyzing the scene and the model. Our approach is to apply continuous LOD to a MPEG-4 compliant model using an extension of Garland's Quadric-Based Surface algorithm. This is achieved with a novel approach that attempts a selective model simplification that is both compatible with MPEG-4 and also could simplify animation streams. [ABSTRACT FROM PUBLISHER]

For solving difficulty of running sluggishly and system overload in 3D simulation based equipment operation simulation system, 3D model optimization technologies including polygon simplification, instance reference and LOD are adopted combing with system characteristics of EOSS. Finally, 3D model optimization examples consists of single equipment and integrated equipment are also presented to prove its feasible and effective. [ABSTRACT FROM PUBLISHER]

In the virtual reality technology, simulate the different weather can increase the realism, the particles of the rain and snow is usually realized by the particle system. While, when the particles reach to certain orders of magnitude. It is difficult to achieve real-time effects. LOD technology means control of details, based on the research of particle system and LOD technology, the author puts forward a new idea. According to the theory of human visual depth, combining the particle system, utilizing the LOD technology, to load the different models and display on the basis of the distance between the particle and the observation, and this method will save the space, and improve the efficiency. [ABSTRACT FROM PUBLISHER]

The problem of massive data 3D-visualization is to use the algorithm optimization techniques in a certain hardware conditions, to keep a 3D visualization software run normally and maximize the speed of response of the software on the user's instruction in the process of dealing with massive data. The essence of the massive data 3D-visualization is rooted in that the computer hardware can not meet data processing requirements. The software technology in the algorithm can only make the software handle more data in the same hardware condition. There are two important problems in the massive data D-Visualization process which are storage capacity bottleneck and computing capacity bottlenecks. Massive data dynamic scheduling technology and LOD technology are the measures to react the above two problems. [ABSTRACT FROM PUBLISHER]