OpenCASCADE 平面求交 eryar@163.com OpenCASCADE提供了类IntAna_QuadQuadGeo用来计算两个二次曲面quadric(球面.圆柱面.圆锥面及平面,平面是二次曲面的特例)之间的交线.他们之间可能的结果有: l 一个点 l 一条或两条直线 l 一个点和一条直线 l 圆 l 椭圆 l 抛物线 l 双曲线 将源码结合<高等数学>.<解析几何>等书,可以来学习如何将理论付诸实践.本文主要介绍这个类中两个平面求交的源码实现.从源码中也可以看出Ope

OpenCASCADE Conic to BSpline Curves-Hyperbola eryar@163.com Abstract. Rational Bezier Curve can represent conic curves such as circle, ellipse, hyperbola, .etc. But how to convert a conic curve to BSpline curve is still question, i.e. Represent a con

Delaunay Triangulation in OpenCascade eryar@163.com 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 一. 概述 三角剖分是平面剖分中的一个重要课题,在数字图像处理.计算机三维曲面造型.有限元计算.逆向工程等领

Surface Normal Vector in OpenCascade eryar@163.com 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,

OpenCascade Shape Representation in OpenSceneGraph eryar@163.com 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

OpenCASCADE 基础 转载▼ 一直在用OCC作项目,但这方面的中文资料很少,看来OCC在中国还不是十分普及: 后来,项目中使用OCC和DirectX结合使用,取得了很好的效果: 随着OCC6.3版本的推出,Open CASCADE在速度方面已有了很大的改变.以下为一些OCC的基础知识,愿与各位OCC爱好者共同学习: 一:OCC中的基础类: gp_Pnt 在OCC中,gp_Pnt表示一个顶点,gp_Vec表示一个向量,可以用两个顶点来生成一个向量. 比如: gp_Pnt P1(0,0,0)

Two analytical 2d line intersection in OpenCASCADE eryar@163.com Abstract. OpenCASCADE geometric tools provide algorithms to calculate the intersection of two 2d curves, surfaces, or a 3d curve and a surface. Those are the basis of the Boolean Operat

1. chamfer 倒角 vs fillet  圆角: 2.boolean operatiron(布尔操作): common(相加),fuse(相交),cut(相减): 3.depressions(凹陷), protrusions(突起), ribs and grooves(凹槽) or slots(槽) along planar(平面) or revolution surfaces(旋转平面) 4.OpenCascade图像文件格式:VRML (Virtual Reality Modelin

OpenCASCADE解非线性方程组 eryar@163.com Abstract. 在科学技术领域里常常提出求解非线性方程组的问题,例如,用非线性函数拟合实验数据问题.非线性网络问题.几何上的曲线曲面求交问题等.OpenCASCADE中有关于非线性方程组定义的类及其求解类,本文主要介绍如何在OpenCASCADE中定义非线性方程组,及对其进行求解. Key Words. Function Set, Function Set Root, Newton Raphson Algorithm 1.In

OpenCascade Sweep Algorithm eryar@163.com Abstract. Sweeps are the objects you obtain by sweeping a profile along a path. Sweep is a very useful modeling algorithm. The paper focus on the introduction of the sweep algorithms in the opencascade. Key W

Intersection between 2d conic in OpenCASCADE eryar@163.com Abstract. OpenCASCADE provides the algorithm to implement of the intersection between two 2d conic curve. The conic is defined by its implicit quadaratic equation, so the intersection problem

Intersection between a 2d line and a conic in OpenCASCADE eryar@163.com Abstract. OpenCASCADE provides the algorithm to implementation of the analytical intersection between a 2d line and another conic curve. The conic is defined by its implicit quad

OpenCASCADE 平面与球面求交 eryar@163.com OpenCASCADE提供了类IntAna_QuadQuadGeo用来计算两个二次曲面quadric(球面.圆柱面.圆锥面及平面,平面是二次曲面的特例)之间的交线.他们之间可能的结果有: l 一个点 l 一条或两条直线 l 一个点和一条直线 l 圆 l 椭圆 l 抛物线 l 双曲线 将源码结合<高等数学>.<解析几何>等书,可以来学习如何将理论付诸实践.本文主要介绍这个类中平面与球面求交的源码实现.  将源码列出如

OpenCASCADE AIS Manipulator eryar@163.com 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 attach

Convert BSpline Curve to Arc Spline in OpenCASCADE eryar@163.com Abstract. The paper based on OpenCASCADE algorithms to approximate the NURBS curve to arc spline. The method is most useful in numerical control to drive the cutter along straight line

OpenCASCADE Shape Location eryar@163.com Abstract. The TopLoc package of OpenCASCADE gives resources to handle 3D local coordinate systems called Locations. A Location is a composition of elementary coordinate systems, each one is called a Datum. The

OpenCASCADE BRep Projection eryar@163.com 一网友发邮件问我下图所示的效果如何在OpenCASCADE中实现,我的想法是先构造出螺旋线,再将螺旋线投影到面上. 为了验证我的想法,结合原来螺旋线的造型算法,来测试下这种效果的实现.依然采用Tcl脚本在Draw Test Harness中试验.个人觉得高效使用OpenCASCADE的方法应该也是先用Tcl脚本来验证一些想法后,再根据使用到的命令找到OpenCASCADE中DRAW的命令实现,最后再可以根据DRA

OpenCASCADE Expression Interpreter by Flex & Bison eryar@163.com 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. Th

OpenCASCADE Data Exchange - 3D PDF eryar@163.com 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

OpenCASCADE Interpolations and Approximations eryar@163.com 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 al

OpenCASCADE Ring Type Spring Modeling eryar@163.com 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