随笔分类 - 5. Visualization
Visualization in Open CASCADE Technology is based on the separation of modeling data you want to display and select, and on the graphical presentation of its structure.
摘要：Abstract. AVEVA Review is used to 3D model visualization for plant or ship design, construction and operation. Taking data from a range of 3D design systems, AVEVA Review delivers a virtual reality view of a plant or ship which users from all disciplines can freely navigate to view areas of interest, communicate ideas or undertake reviews. Use AVEVA .Net can extract model from DESIGN database, and use AnyCAD .Net can visualize the model. This paper mainly focus on the usage of AnyCAD .Net, and a
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摘要：在OpenCascade的显示模块中，可以设置线型、消隐方式和离散精度等属性。这些属性都是在AIS_Drawer中设置。
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摘要：摘要Abstract：本文对网格数据结构作简要介绍，并结合使用OpenCascade中的数据结构，将网格数据在OpenSceneGraph中可视化。
关键字KeyWords：OpenCascade、OpenSceneGraph、Triangulation、Mesh Data Structure
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摘要：Abstract. Rendering a generic surface is a two steps process: first, computing the points that will form the mesh of the surface and then, send this mesh to 3D API. Use the Triangle to triangulate the parametric space and then lifting map to the model 3D space. This is the main method to visualize the generic shaded surface. This paper show the OpenCascade triangulation of the parametric space and the map result: mesh in 3D model space. Use the method can visualize a generic surface.
Key wor
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摘要：Abstract. Triangle is a 2D quality mesh generator and Delaunay triangulator. Triangle was created as part of the Quake project in the school of Computer Science at Carnegie Mellon University by Jonathan R. Shewchuk. Triangle is a small C program and its Delaunay refinement algorithm for quality mesh generation is a hybrid one. It includes divide-and-conquer and incremental insertion algorithms and sweepline Delaunay triangulation algorithm. This paper is focused on the usage of the Triangle and
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摘要：Abstract. MeshVS means Mesh Visualization Service. It can be used to representation mesh in different style, such as colored stress patterns mesh, mesh with text and mesh like vector(with arrow). So MeshVS usually used for CAE programming. This paper focus on the MeshVS usage.
Key words. OpenCascade, Mesh, MeshVS, Colored stress Patterns
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摘要：摘要Abstract：正确设置网格面上点的法向，对几何体在光照等情况下显示得更真实，这样就可以减少顶点数量，提高渲染速度。本文通过将OpenCascade中的形状离散成网格数据后在OpenSceneGraph中显示，及使用OSG的快速法向osgUtil::SmoothingVisitor优化与使用OpenCascade来计算正确的法向的结果的对比，说明面法向量的重要性。
关键字Key Words：OpenCascade, OpenSceneGraph, Normal Averaging, Triangulation Mesh
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摘要：摘要Abstract：表面上某一点的法向量（Normal Vector）指的是在该点处与表面垂直的方向。对于平面，其上各点的法向是一样的，统一为这个平面的法向。对于曲面，各点具有不同的法向量。几何对象的法向量定义了它在空间中的方向，法向量是在进行光照处理时的重要参数。所以在显示造型算法离散曲面后的网格时，设置正确的法向量对场景的光照、光线追踪效果有直接影响。本文结合OpenCascade中代码，对其法向量的计算方法进行分析，稍加修改即可用到实际的程序中。
关键字Key Words：OpenCascade, Normal Vector, Mesh Normal, OpenSceneGraph
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摘要：摘要Abstract：OpenCascade6.7.0中引入了光线跟踪算法的实现。使用光线跟踪算法可实现高质量的渲染效果，且可以使用GPU提升渲染效率。
关键字Key Words：OpenCascade, Visualization, Ray Tracing
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摘要：摘要Abstract：本文主是对Netgen的库nglib的用法进行介绍。主要参考资料是Netgen用户指南。最后给出一个具体程序实例。
关键字Key Words：Netgen, nglib, Mesh
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摘要：摘要Abstract：本文主要介绍如何对下载的Netgen源码进行编译生成Netgen程序和程序开发所需要的库nglib。
关键字Key Words：Netgen, nglib, Mesh Generator, OpenCascade, Triangulation
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摘要：摘要Abstract：本文主要对工厂和海工设计软件AVEVA的交互方式进行详细介绍，对OpenSceneGraph中的人机交互工具拖拽器进行说明，并在其中实现了模型直接交互操作。对交互建模感兴趣的读者可结合其源代码，对其实现细节进行分析。
关键字Key Words：AVEVA, Model Editor, OpenSceneGraph, Dragger
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摘要：摘要Abstract：现在的显示器大多数是光栅显示器，即可以看做一个像素的矩阵。在光栅显示器上显示的任何图形，实际上都是一些具有一种或多种颜色的集合。数学上精确表示的图形在显示器中只能用逼近的方式显示出来。本文主要对OpenCascade的BRep文件中用来显示曲线和曲面的离散数据结构进行说明。
关键字：OpenCascade, BRep, Polygon, Triangulation, Subdivision Curves,
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摘要：摘要Abstract：本文通过程序实例，将OpenCascade中的拓朴数据（边、面）离散化后在OpenSceneGraph中进行显示。有了这些离散数据，就可以不用OpenCascade的显示模块了，可以使用其他显示引擎对形状进行显示。即若要线框模式显示形状时，就绘制离散形状拓朴边后得到的多段线；若要实体渲染模式显示形状时，就绘制离散形状拓朴面得到的三角网格。理解这些概念也有助于理解显示模块的实现，及拓朴数据中包含的几何数据的意义。
关键字 Key Words：OpenCascade, polygon curve, triangulation,discrete edge, discrete face, OpenSceneGraph, OSG
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