Open CASCADE学习| 几何建模

目录

1、二维几何

gp_XY定义二维坐标值

gp_Pnt2d定义二维点

gp_Dir2d描述了二维空间中的一个单位向量。

gp_Vec2d描述了二维空间中的一个向量。

2、三维几何

gp_XYZ定义三维坐标值

gp_Pnt定义三维点

gp_Dir描述了三维空间中的一个单位向量。

gp_Ax1定义旋转轴、对称轴、直线的方向等

gp_Ax2定义几何位置（几何的Position即是此坐标系的原点），如圆的位置，球体的位置。

gp_Ax3与Ax2基本一致，只是其可以定义为左旋坐标系。

3、创建直线段

4、创建圆

5、Bezier曲线

6、Bezier和直线围城曲面

7、在曲线上生成点

8、创建带孔面

9、创建圆形拉伸面

10、创建圆形拉伸面

11、在曲面上生成点

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1、二维几何

gp_XY定义二维坐标值

gp_Pnt2d定义二维点

gp_Dir2d描述了二维空间中的一个单位向量。

gp_Vec2d描述了二维空间中的一个向量。

2、三维几何

gp_XYZ定义三维坐标值

gp_Pnt定义三维点

gp_Dir描述了三维空间中的一个单位向量。

gp_Ax1定义旋转轴、对称轴、直线的方向等

gp_Ax2定义几何位置（几何的Position即是此坐标系的原点），如圆的位置，球体的位置。

gp_Ax3与Ax2基本一致，只是其可以定义为左旋坐标系。

3、创建直线段

#include 
#include 
#include 
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    //两点创建直线
    gp_Pnt P1(0., 0., 0.);
    gp_Pnt P2(0., 10., 0.);
    GC_MakeSegment MC(P1, P2);
    Handle(Geom_TrimmedCurve) C = MC.Value();
    TopoDS_Edge edge11 = BRepBuilderAPI_MakeEdge(C);
    Viewer vout(50, 50, 500, 500);
    vout << edge11;
    vout.StartMessageLoop();
    return 0;
}

4、创建圆

#include 
#include 
#include 
#include 
#include 
#include 
​
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    //三点创建圆弧
    gp_Pnt P1(0., 0., 0.);
    gp_Pnt P2(0., 10., 0.);
    gp_Pnt P3(10., 0., 0.);
    gce_MakeCirc MC(P1, P2, P3);
    if (MC.IsDone())
    {
        const gp_Circ& C = MC.Value();
    }
    else {
        gce_ErrorType type = MC.Status();
        //对各种错误进行处理
    }
    TopoDS_Edge edge11 = BRepBuilderAPI_MakeEdge(MC);
    Viewer vout(50, 50, 500, 500);
    vout << edge11;
    vout.StartMessageLoop();
    return 0;
}

5、Bezier曲线

#include 
#include 
#include 
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    //Non Rational B-Spline
​
    gp_Pnt points1[8] = {
    gp_Pnt(0.0,-100.0,0.0),
    gp_Pnt(10.0,10.0,0.0),
    gp_Pnt(30.0,-100.0,0.0),
    gp_Pnt(100.0,0.0,0.0),
    gp_Pnt(150.0,50.0,0.0),
    gp_Pnt(200.0,0.0,0.0),
    gp_Pnt(400.0,200.0,0.0),
    gp_Pnt(450.0,0.0,0.0)
    };
​
    NCollection_Array1 points(points1[0], 1, 8);//Control points
    Standard_Real realsWeight[8] = { 1.0,1.0,1.0,1.0,1.0,1.0,10.0,1.0 };
    NCollection_Array1 weight(realsWeight[0], 1, 8);//权系数，倒数第二个点的权系数是其他的10倍。
    Geom_BezierCurve bezier(points); //Non-Rational
​
    Geom_BezierCurve rationalBezier(points, weight);//Rational
    Handle(Geom_BezierCurve) bezier1 = &bezier;
    Handle(Geom_BezierCurve) bezier2 = &rationalBezier;
    TopoDS_Edge edge11 = BRepBuilderAPI_MakeEdge(bezier1);
    TopoDS_Edge edge12 = BRepBuilderAPI_MakeEdge(bezier2);
    Viewer vout(50, 50, 500, 500);
    vout << edge11;
    vout << edge12;
    vout.StartMessageLoop();
    return 0;
}

6、Bezier和直线围城曲面

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    gp_Pnt pointsSur1[4] = 
    { 
        gp_Pnt(0.0,0.0,0.0),
        gp_Pnt(100.0,100.0,0.0),
        gp_Pnt(150.0,20.0,0.0),
        gp_Pnt(300.0,0.0,0.0)
    };
    gp_Pnt pointsSur2[4] = 
    { 
        gp_Pnt(0.0,0.0,0.0),
        gp_Pnt(-20,-50.0,0.0),
        gp_Pnt(20.0,-150.0,0.0),
        gp_Pnt(100.0,-300.0,0.0)
    };
    NCollection_Array1 pointsFace1(pointsSur1[0], 1, 4);
    NCollection_Array1 pointsFace2(pointsSur2[0], 1, 4);
    Geom_BezierCurve bezierFace1(pointsFace1);
    Geom_BezierCurve bezierFace2(pointsFace2);
    Handle(Geom_BezierCurve) bezierSur1 = &bezierFace1;
    Handle(Geom_BezierCurve) bezierSur2 = &bezierFace2;
    TopoDS_Edge edgeSur1 = BRepBuilderAPI_MakeEdge(bezierSur1);
    TopoDS_Edge edgeSur2 = BRepBuilderAPI_MakeEdge(bezierSur2);
    TopoDS_Edge edgeSur3 = BRepBuilderAPI_MakeEdge(gp_Pnt(300.0, 0.0, 0.0), gp_Pnt(100.0, -300.0, 0.0));
    TopoDS_Wire wireSur = BRepBuilderAPI_MakeWire(edgeSur1, edgeSur2, edgeSur3);
    TopoDS_Face face = BRepBuilderAPI_MakeFace(wireSur);
    Viewer vout(50, 50, 500, 500);
    vout << face;
    vout.StartMessageLoop();
    return 0;
}

7、在曲线上生成点

Handle(Geom_Curve) mycurve = ... ;
GeomAdaptor_Curve C (mycurve);
​
GCPnts_UniformDeflection myAlgo ();
Standard_Real Deflection = ... ;// 定义容差
myAlgo.Initialize (C, Deflection);
if (myAlgo.IsDone())
{
  Standard_Integer nbr = myAlgo.NbPoints();//生成点的个数
  Standard_Real param;
  for (Standard_Integer i = 1; i <= nbr; i++)
  {
    param = myAlgo.Parameter (i);// 获取每个点的参数
    gp_Pnt p=mycurve->Value(param); //得到点
    ...
  }
}

8、创建带孔面

 Point->Curve->Edge->Wire->Face

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
​
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    gp_Pnt p1(0.0, 0.0, 0.0);
    gp_Pnt p2(100.0, 0.0, 0.0);
    gp_Pnt p3(100.0, 100.0, 0.0);
    gp_Pnt p4(0.0, 100.0, 0.0);
    gp_Pnt center(50.0, 50.0, 0.0);
    gp_Dir  Z(0.0, 0.0, 1.0);
    gp_Ax2  coor(center, Z);
    gp_Circ  circle(coor, 20.0);
    Handle(Geom_TrimmedCurve) triCurve1 = GC_MakeSegment(p1, p2);
    Handle(Geom_TrimmedCurve) triCurve2 = GC_MakeSegment(p2, p3);
    Handle(Geom_TrimmedCurve) triCurve3 = GC_MakeSegment(p3, p4);
    Handle(Geom_TrimmedCurve) triCurve4 = GC_MakeSegment(p4, p1);
    Handle(Geom_Circle) triCurve5 = GC_MakeCircle(circle); //hole
    //Edge,topology                         
    TopoDS_Edge e1 = BRepBuilderAPI_MakeEdge(triCurve1);
    TopoDS_Edge e2 = BRepBuilderAPI_MakeEdge(triCurve2);
    TopoDS_Edge e3 = BRepBuilderAPI_MakeEdge(triCurve3);
    TopoDS_Edge e4 = BRepBuilderAPI_MakeEdge(triCurve4);
    TopoDS_Edge e5 = BRepBuilderAPI_MakeEdge(triCurve5);//可以直接接受一个circle
    //comibe edge to wire:wire is the assembly of edges, BRepBuilderAPI_MakeWire class can build a wire from one or more edges or connect new edges to an existing wire.
    TopoDS_Wire wire = BRepBuilderAPI_MakeWire(e1,e2,e3,e4);
    TopoDS_Wire  hole = BRepBuilderAPI_MakeWire(e5);
    //create face:Use BRepBuilderAPI_MakeFace class to create a face from a surface and wires
    TopoDS_Face face = BRepBuilderAPI_MakeFace(wire);
    TopoDS_Face holeFace = BRepBuilderAPI_MakeFace(hole);
    //Boolean Operation，face-holeFace
    TopoDS_Shape shape = BRepAlgoAPI_Cut(face, holeFace);
​
    Viewer vout(50, 50, 500, 500);
    vout << shape;
    vout.StartMessageLoop();
    return 0;
}

9、创建圆形拉伸面

#include 
#include 
#include 
#include 
#include 
#include 
​
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    gp_Pnt center(50.0, 50.0, 0.0);
    gp_Dir  Z(0.0, 0.0, 1.0);
    gp_Ax2  coor(center, Z);
    gp_Circ  circle(coor, 20.0);
    Handle(Geom_Circle) triCurve5 = GC_MakeCircle(circle);
    TopoDS_Edge e5 = BRepBuilderAPI_MakeEdge(triCurve5);
    gp_Vec aPrismVec(0, 0, 20);
    TopoDS_Shape myBody = BRepPrimAPI_MakePrism(e5, aPrismVec);//first parameter is TopoDS_Shape
    Viewer vout(50, 50, 500, 500);
    vout << myBody;
    vout.StartMessageLoop();
    return 0;
}

10、创建圆形拉伸面

#include 
#include 
#include 
#include 
#include 
#include 
​
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    gp_Ax2 cooor(gp_Pnt(0.0, 0.0, 0.0), gp_Dir(0.0, 0.0, 1.0));
    gp_Hypr hyperbolaGp(cooor, 20.0, 8.0);
    Handle(Geom_Hyperbola) hyperbolaGeom = GC_MakeHyperbola(hyperbolaGp);
    TopoDS_Edge edge1 = BRepBuilderAPI_MakeEdge(hyperbolaGeom, 0.1, 1.0);//将双曲线的某一部分形成Edge，至于两个参数如何控制，不懂。
    gp_Vec aPrismVec(10, 0, 0);
    TopoDS_Shape myBody = BRepPrimAPI_MakePrism(edge1, aPrismVec);
    Viewer vout(50, 50, 500, 500);
    vout << myBody;
    vout.StartMessageLoop();
    return 0;
}

11、在曲面上生成点

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include"Viewer.h"
​
​
​
int main(int argc, char* argv[])
{
    std::vector verts; //点集合
    const Standard_Real pi = 3.1415926;
    gp_Sphere aSpere(gp_Ax2(), 10);
    TopoDS_Face aSpFace = BRepBuilderAPI_MakeFace(aSpere, 0.0, 2 * pi, -pi / 2, pi / 2);
    IMeshTools_Parameters aMeshParams; //离散的准则
    aMeshParams.Deflection = .01;
    aMeshParams.Angle = 0.1;
    aMeshParams.Relative = Standard_False;
    aMeshParams.InParallel = Standard_True;
    aMeshParams.MinSize = Precision::Confusion();
    aMeshParams.InternalVerticesMode = Standard_True;
    aMeshParams.ControlSurfaceDeflection = Standard_True;
    aMeshParams.InParallel = Standard_False;
    BRepMeshData_Face MeshFace(aSpFace, new NCollection_IncAllocator);
    BRepMesh_SphereRangeSplitter mySplitter;
    mySplitter.Reset(&MeshFace, aMeshParams);
​
    //此处是使BRepMesh_SphereRangeSplitter获得正确的UV参数范围；
    //在OCC的Mesh中，在MeshAlgo里边也调用了AddPoint()方法。
​
    BRepAdaptor_Surface BS1(aSpFace);
    Standard_Real u_1 = BS1.FirstUParameter();
    Standard_Real u_2 = BS1.LastUParameter();
    Standard_Real v_1 = BS1.FirstVParameter();
    Standard_Real v_2 = BS1.LastVParameter();
​
    gp_Pnt2d p0(u_1, v_1);
    gp_Pnt2d p1(u_1, v_2);
    gp_Pnt2d p2(u_2, v_1);
    gp_Pnt2d p3(u_2, v_2);
    //
​
    mySplitter.AddPoint(p0);
    mySplitter.AddPoint(p1);
    mySplitter.AddPoint(p2);
    mySplitter.AddPoint(p3);
​
    mySplitter.AdjustRange();
​
    Handle(IMeshData::ListOfPnt2d) nodes2D = mySplitter.GenerateSurfaceNodes(aMeshParams);
    for (auto iter = nodes2D->begin(); iter != nodes2D->end(); iter++) {
        gp_Pnt pnd3D = mySplitter.Point(*iter);
        TopoDS_Vertex aVer = BRepBuilderAPI_MakeVertex(gp_Pnt((*iter).X(), (*iter).Y(), 0));
​
        verts.push_back(aVer);
    }
  
    Viewer vout(50, 50, 500, 500);
    std::vector::iterator it = verts.begin();
    while (it != verts.end())
    {
        vout << *it;
        it++;
    }
    vout.StartMessageLoop();
    return 0;
}