摘要:
对于几何造型内核OpenCASCADE,由于会涉及到大量的数值算法,如矩阵相关计算,微积分,Newton迭代法解方程,以及非线性优化的一些算法,如BFGS,FRPR,PSO等等用于多元函数的极值求解,所以这些数值算法的性能直接影响系统的性能。软件的性能优化是计算机软件开发过程中需要一直关注的重要因素,因此有必要学习下C++应用程序性能优化的方法。
在网上寻找相关资料时,发现这方面的资料也很少,最后发现一本由电子工业出版社出版的《C++应用程序性能优化方法》,从中可以学习下IBM的性能优化方法。
本文主要结合《C++性能优化方法》并结合代码实例来说明内存优化处理对程序性能的影响。看完本书,其实发现C++性能优化方法主要还是依赖的计算机相关的基础知识,比如说计算机操作系统,数据结构与算法等等。 阅读全文
摘要:
Abstract. OpenCASCADE provide data structure of any expression, relation or function used in mathematics. Flex and Bison are tools for building programs that handle structured input. They were originally tools for building compilers, but they have proven to be useful in many other areas. The Expression Interpreter in OpenCASCADE is made by Flex and Bison. So let’s know something about Flex and Bison.
Key Words. OpenCASCADE, Expression Interpreter, Flex, Bison 阅读全文
摘要:
本文主要描述如何修改FreeCAD的Branding,从而使自己能基于FreeCAD灵活的架构快速开发出自己的应用程序。通过修改FreeCAD的Branding甚至启动画面,从而使程序看上去更像是自己开发的。 阅读全文
摘要:
FreeCAD是一个参数化的三维造型软件,主要用于任意大小的实际模型的设计。参数化的建模方式可以通过修改相关参数从而方便地修改你的设计。FreeCAD是开源软件,并提供了便利地自定义方式,也提供了脚本,从而根据自己的需要去扩展功能。FreeCAD是跨平台(Windows, Mac和Linux),可以读写许多开放的模型文件,如STEP,IGES,STL,SVG,DXF,OBJ,IFC,DAE等。
如果说学习OpenCASCADE可以了解一些几何内核底层的算法,那么学习FreeCAD则可以用来实现一些具体的功能,从而将三维的技术应用到实际的生活中去,创造出有意义的功能。
本文详细说明如何在Windows平台上编译FreeCAD源码。如果你已经可以正常编译OpenCASCADE这种开源库的源码,那么编译FreeCAD还是很简单的。 阅读全文
摘要:
Abstract. Today most 3D engineering model data are save to 3D PDF files. Universal 3D(U3D) along side Product Representation Compact(PRC), U3D is the historical foundation used to embed 3D interactive data and models into a PDF file. But PRC is now the preferred and most feature-rich method to embed 3D data into a PDF file. So the paper is focus on to translate OpenCASCADE geometry data to 3D PDF by embedding PRC file.
Key Words. PDF 3D, OpenCASCADE, U3D, PRC, libharu 阅读全文
摘要:
Abstract. In modeling, it is often required to approximate or interpolate points to curves and surfaces. In interpolation, the process is complete when the curve or surface passes through all the points; in approximation, when it is as close to these points as possible. The paper is the translation of the OpenCASCADE Modeling Data user guide.
Key Words. Interpolation, Approximation, Fitting 阅读全文
摘要:
Tcl内置变量备忘录。 阅读全文
摘要:
Abstract. The general method to directly create an edge is to give a 3D curve as the support(geometric domain) of the edge. The curve maybe defined as a 2D curve in the parametric space of a surface: PCurve. When you understand the pcurve, you can modeling some interesting shapes, such as bottle neck thread, helix spring, ring type spring. Etc. The paper is focus on the Ring Type Spring Modeling in OpenCASCADE Draw Test Harness by Tcl script.
Key Words. Spring, Helix, Tcl/Tk, 环形弹簧 阅读全文
摘要:
鞋博士经过8年沉淀,在鞋类工业4.0全流程平台上积累了相当的技术实力,获投资商亲睐。 新的一年,在投资商协助下,将踏上新的征途,因此诚邀您加盟顶层技术合伙人。 如果您具备以下实力,我们期待您的加盟: 1、熟悉C++ 2、熟悉图形学 3、学过矩阵,优化理论者优先 4、能阅读英文技术文档 5、人品好,踏 阅读全文
摘要:
为了帮助OPEN CASCADE新手顺利编译OPEN CASCADE源码,特录制了一个视频,
有了这个视频,OPEN CASCADE的编译再也不麻烦啦! 阅读全文