ObjectArx中创建圆的函数
AcDbCircle(const AcGePoint3d& cntr, const AcGeVector3d& nrm, double radius);
cntr：圆心
nrm：圆所在平面，用法向量(0,0,1)表示XY平面
radius：半径
如何创建圆
1 AcDbObjectId CCreateEnt::CreateCircle(AcGePoint3d ptCenter, AcGeVector3d vec, DOUBLE radius) 2 { 3 AcDbObjectId oId; 4 AcDbCircle* pCircle = new AcDbCircle(ptCenter,vec,radius); //创建圆 5 6 oId = CCreateEnt::PostToModelSpace(pCircle); //提交到模型空间 7 return oId; 8 9 }
PostToModelSpace函数在上一节实现
创建XY平面上的圆
1 AcDbObjectId CCreateEnt::CreateCircle(AcGePoint3d ptCenter, DOUBLE radius) 2 { 3 AcDbObjectId oId; 4 AcGeVector3d vec(0,0,1); //代表XY平面的法向量 5 AcDbCircle* pCircle = new AcDbCircle(ptCenter,vec,radius); 6 oId = CCreateEnt::PostToModelSpace(pCircle); 7 return oId; 8 }
两点创建圆
1 AcDbObjectId CCreateEnt::CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2) 2 { 3 AcGePoint2d pt = CCalculation::MiddlePoint(pt1,pt2); //获取中点 4 AcGePoint3d ptCenter(pt.x,pt.y,0); 5 DOUBLE radius = pt1.distanceTo(pt2)/2; //获取半径 6 return CCreateEnt::CreateCircle(ptCenter,radius); 7 }
MiddlePoint函数求两个点的中点，这里就不贴出具体实现方法了
三点创建圆
AcDbObjectId CCreateEnt::CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2, AcGePoint2d pt3) { AcGeCircArc2d geArc(pt1,pt2,pt3); //创建AcGeCircArc对象 AcGePoint3d ptCenter(geArc.center().x,geArc.center().y,0); //获取圆心 return CCreateEnt::CreateCircle(ptCenter,geArc.radius()); }
AcGeCircArc2d表示一个几何类的圆弧对象，该对象仅用于计算，不能在图形窗口中显示
测试圆创建功能
1 public: 2 3 // ----- CADShellCreateEntsUnmanaged._AddCircle command 4 static void CADShellCreateEntsUnmanaged_AddCircle(void) 5 { 6 AcGePoint3d ptCenter(100,100,0); 7 CCreateEnt::CreateCircle(ptCenter,20); 8 9 AcGePoint2d pt1(70,100); 10 AcGePoint2d pt2(130,100); 11 CCreateEnt::CreateCircle(pt1,pt2); 12 13 pt1.set(60,100); 14 pt2.set(140,100); 15 AcGePoint2d pt3(100,60); 16 CCreateEnt::CreateCircle(pt1,pt2,pt3); 17 18 }