图核科技

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 阅读全文

摘要： Abstract. Although polynomials offer many advantages, there exist a number of important curve and surface types which cannot be represented precisely using polynomials, e.g., circles, ellipses, hyperbolas, cylinders, cones, spheres, etc. So we introduce the concepts of rational curves and homogeneous coordinates to solve the problem. To understand rational curves in a homogenous coordinate system is more straightforward. If you define irrational Bezier curves in 4D space and then project them ba 阅读全文

摘要： Abstract. Numerical integration is the approximate computation of an integral using numerical techniques. The numerical computation of an integral is sometimes called quadrature. The most straightforward numerical integration technique uses the Newton-Cotes formulas(also called quadrature formulas), which approximate a function tabulated sequence of regularly spaced intervals by various degree polynomials. If the functions are known analytically instead of being tabulated at equally spaced inter 阅读全文

摘要： Abstract. Doxygen is the de facto standard tool for generating documentation from annotated C++ sources, but it also supports other popular programming languages. You can also use doxygen for creating normal documentation, as OpenCASCADE did for its references and user’s guide documents. Key Words. OpenCASCADE, Doxygen, Documentation System 阅读全文

摘要： Abstract. The natural parametric equations of a curve are parametric equations that represent the curve in terms of a coordinate-independent parameter, generally arc length s, instead of an arbitray variable like t or u. According to the natural equations, the curve length is the integration of the curve parametric equation’s derivation. So the core algorithm for curve length calculation is the numerical integration method. OpenCASCADE use Gauss-Legendre to calculate the integration for single v 阅读全文

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 阅读全文

摘要： Abstract. Draw is a command interpreter based on Tcl/Tk and a graphical system used to test and demonstrate OpenCascade modeling libraries. It provides a flexible and easy to use means of testing and demonstrating the OCCT modeling libraries. By a given command of Tcl, you can find the implentation code for that command by OpenCascade, the code could be as a demo to use of OCC modeling libraries. So this is the most effectively way of use OpenCascade. Key words. OpenCascade, Tcl/Tk, Testing, 阅读全文

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 阅读全文

摘要： Abstract. B-splines are quite a bit more flexible than Bezier curves. This flexibility comes from the fact that you have much more control over the basis functions. For Bezier curves that each control point had an effect on each point on the curve; likewise the number of control points affected the degree of the curve. For the sake of flexiblity, you would like to be able to arbitrarily set the degree of the curve and to also determine the range of the affect each control point has. B-splines al 阅读全文

摘要： Abstract. OpenCascade use the Jacobi method to find the eigenvalues and the eigenvectors of a real symmetric square matrix. Use class math_Jacobi to computes all eigenvalues and eigenvectors by using Jacobi method. The exception NotSquare is raised if the matrix is not square. No verification that the matrix is really symmetric is done. Key words. Eigenvalues, Eigenvectors, OpenCascade, Matrix, Jacobi method, 阅读全文