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. Bounding Volume Hierarchy(BVH) organizes geometric objects in the tree based on spatial relationships. Each node in the tree contains an axis-aligned bounding box of all the objects below it. Bounding volume hierarchies are used in many algorithms to support efficient operations on the sets of geometric objects, such as collision detection, ray-tracing, searching of nearest objects, and view frustum culling. The paper focus on the usage of BVH on TopoDS_Shape, and its application.
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摘要：Abstract. EasyMesh is developed by Bojan Niceno, it is a two-dimensional quality mesh generator. EasyMesh can generate two dimensional, unstructured, Delaunay and constrained Delaunay triangulations in general domains. It can handle holes in the domain. The paper focus on the usage of EasyMesh.
Key Words. EasyMesh, Delaunay Triangualtion, Triangulation, Mesh
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摘要：Abstract. OpenCASCADE7.1.0 introduces new built-in interactive object AIS_Manipulator providing interface for moving objects within 3D viewer. The class features three kinds of transformation modes for attached objects: translation through axis, scaling within axis, rotation around axis. The object can be activated using vmanipulator command within Draw Test Harness.
Key Words. OpenCASCADE, 3D Viewer Interactive, Model Editor, Manipulator
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摘要：Abstract. Qt’s ActiveX and COM support allows Qt for Windows developers to access and use ActiveX controls and COM objects provided by any ActiveX server in their Qt applications. Make their Qt application available as COM servers, with any number of Qt objects and widgets as COM objects and ActiveX controls. Make OpenSceneGraph to ActiveX controls then you can use it in other place, like IE.
Key Words. OpenSceneGraph, ActiveX, COM, ActiveQt
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摘要：Abstract. The Voronoi extension of the Boost.Polygon library provides functionality to construct a Voronoi diagram of a set of points and linear segments in 2D space with some limitations. The paper mainly describles how to compile the boos voronoi visualizer and use it show the example voronoi diagram result.
Key Words. Boost, Voronoi, Visualizer
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摘要：Abstract. As implementation of one of the strategic steps in OpenCASCADE visualization component development road-map, support for GLSL shader programs has been added in OpenCASCADE Technology 6.7.0.
Key Words. OpenCASCADE, GLSL, Shader, Gooch Shader
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摘要：Abstract. The OpenGL Shading Language syntax comes from the C family of programming languages. Tokes, identifiers, semicolons, nesting with curly braces, control-flow, and many key words look like C. GLSL provides three qualifiers which form the interfaces of the shaders to their outside world.
Key Words. OpenGL, GLSL, Qualifiers,
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摘要：Abstract. OpenGL Shading Language, the high-level programming language defined to allow application writers to write programs that execute on the programmable processors defined within OpenGL. Informally the language is sometimes referred to as GLSL. The GLSL has been made part of the OpenGL standard as of OpenGL2.0. The paper focus on a simple example of OpenGL Shader, which can be used as a guide of GLSL.
Key Words. OpenGL, OpenGL Shading Language, GLSL, Shader, Qt
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摘要：Abstract. Siemens’ JT data format accepted as the world’s first ISO international standard for viewing and sharing lightweight 3D product information. OpenCASCADE JT Assistant is a viewer for files in JT format.
Key Words. Simens JT, JtOpen, OpenCASCADE, Jt Assistant
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摘要：Abstract. When you finish modeling objects in the scene, you must want to use some operations to view the scene objects, such as Pan, Zoom and Rotate the scene. Pan and Zoom is easy to understand, rotate the 3D scene according to 2D point in the viewport is a little complicated. There are many methods to rotate the 3D scene, but the Arcball Controller is intuitive for the user and any viewport can be described. You can rotate your model at will just by using the mouse.
Key Words. OpenCASCADE
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摘要：Abstract. The purpose of the OpenGL graphics processing pipeline is to convert 3D descriptions of objects into a 2D image that can be displayed. In many ways, this process is similar to using a camera to convert a real-world scene into a 2D print. To accomplish the transformation from 3D to 2D, OpenGL defines several coordinate spaces and transformations between those spaces. Each coordinate space has some properties that make it useful for some part of the rendering process. The transformations
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摘要：Abstract. OpenCASCADE introduce a new class Graphic3d_Camera for the Visualization module. The camera class provides object-oriented approach to setting up projection and orientation properties of 3D view. The paper use GLUT to test the function of the new Camera class.
Key Words. OpenCASCADE, Camera, OpenGL, GLUT, Transformations
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摘要：Abstract. The quaternions are members of a noncommutative division algebra first invented by William Rowan Hamilton. The idea for quaternions occurred to him while he was walking along the Royal Cannal on his way to a meeting of the Irish Academy, and Hamilton was so pleased with his discovery that he scratched the fundamental formula of quaternion algebra. There are several different ways we can express orientation and angular displacement in 3D. Here we discuss the three most important methods
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摘要：Abstract. The openNURBS Toolkit consists of C++ source code for a library that will read and write a openNURBS 3D model file(.3dm). More than 400 software development teams and applications including Rhinoceros, exchange 3-D models using the openNURBS (.3dm) file format. But there is no a simple viwer for 3dm on PC except Rhinoceros. So I want to develop a 3DM viewer based on OpenSceneGraph to visualize the 3DM file.
Key Words. OpenNURBS, 3DM Viewer, OpenSceneGraph
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摘要：Abstract. The color scale is a specialized label object that displays a color map and an accompanying numerical scale for color mapped or contour data plots. As the geometry modeling kernel of SALOME, OpenCASCADE provides the color scale function. The paper focus on the usage of color scale in OpenCASCADE.
Key Words. OpenCASCADE, Color Scale, 应力云图, 颜色映射表
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摘要：Abstract. OpenCascade uses advanced text rendering powered by FTGL library. The FreeType provides vector text rendering, as a result the text can be rotated and zoomed without quality loss. FreeType also support unicode charset. The paper focus on the Chinese Text rendering.
Key Words. OpenCascade, FreeType, Chinese Text, 中文汉字, Unicode
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摘要：Abstract. Delaunay Triangulation is the core algorithm for mesh generation. By Delaunay Triangulator you can make a general method to visualize geometry surfaces, so does OpenCascade. The paper focus on the geometry surfaces visualization, include the surfaces with holes.
Key words. OpenCascade, Delaunay Triangulator, OpenSceneGraph, Mesh, NURBS
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摘要：摘要：本文简要介绍了Delaunay三角剖分的基础理论，并使用OpenCascade的三角剖分算法将边界BRep表示的几何体进行三角离散化后在OpenSceneGraph中显示。
关键字：Delaunay Triangulation、OpenCascade、OpenSceneGraph
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摘要：Abstract. One of the important features of the boost polygon library is the implementation of the generic sweepline algorithm to construct Voronoi diagrams of points and linear segments in 2D(developed as part of the Google Summer of Code 2010 program). Voronoi diagram data structure has applications in image segmentation, optical character recognition, nearest neighbor queries execution. It is closely related with the other computational geometry conectps: Delaunay triangulation, medial axis, s
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摘要：Abstract. In mathematics a Voronoi diagram is a way of dividing space into a number of regions. A set of points, called seeds, sites, or generators is specified beforehand and for each seed there will be a correspoinding region consisting of all points closer to that seed than to any other. The regions are called Voronoi cells. It is dual to the Delaunay triangulation. It is named after Georgy Voronoy, and is also called a Voronoi tessellation, a Voronoi decomposition, a Voronoi partition, or a
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