画椭圆 draw Ellipse

[liqi98136]

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import "ecere"
 
 
class Ellipse : Surface
{
   private:
     Array<Point> arrayPoint;
   public:
     Point Origin;   //原点
	  int Ra, Rb;		// 椭圆弧的长轴和短轴
	  int nStep;			// 四分之一椭圆弧要用多少段直线描述  
 
   property Point Origin
     {
        get {return Origin;}
        set {Origin = value;}
     }
   property int Ra
     {
        get {return Ra;}
        set {Ra = value;}
     }
   property int Rb
     {
        get {return Rb;}
        set {Rb = value;}
     }
   property int nStep
     {
        set {nStep = value;}
     }
     Ellipse()
     {
       nStep = 8;
       arrayPoint =Array<Point>{};
     };
 
     void setStep( int Step )
     {
       nStep = Step;
     };
 
     // 返回圆周上的点
     void returnRound()
     {
      int i;
      //int m = nStep*4;
      double n = 90.0/nStep/180.0*Pi;  
      Array<Point> m_point{};
 
      for( i=0; i<=nStep; ++i )   
       {   
           Point point{};
           point.x = (int)(Ra*sin( i*n ));   
           point.y = (int)(Rb*cos( i*n ));   
 
           m_point.Add(point);   
       } 
 
    // 将[0,90]椭圆弧上的点扩充成整椭圆上的点，同时将圆心放到指定位置    
    // 已知第一象限的点(x,y)，用对称的方法可以生成另外三个象限的点。生成方法是：    
    // 第二象限(x,y)-->(x,-y)    
    // 第三象限(x,y)-->(-x,-y)    
    // 第四象限(x,y)-->(-x,y)
 
    // 第一象限
      for( i=0; i<=nStep; ++i )   
       {   
            Point point{};
           point.x = m_point[i].x + Origin.x;   
           point.y = m_point[i].y + Origin.y;   
 
           arrayPoint.Add(point);   
       }
       // 第二象限
      for( i=nStep; i>=0; --i )   
       {   
           Point point{};
           point.x = m_point[i].x + Origin.x;   
           point.y = -m_point[i].y + Origin.y;   
 
           arrayPoint.Add(point);   
       }
        // 第三象限   
      for( i=0; i<=nStep; ++i )   
       {   
           Point point{};
           point.x = -m_point[i].x + Origin.x;   
           point.y = -m_point[i].y + Origin.y;   
 
           arrayPoint.Add(point);   
       }   
        // 第四象限
      for( i=nStep; i>=0; --i )   
       {   
           Point point{};
           point.x = -m_point[i].x + Origin.x;   
           point.y = m_point[i].y + Origin.y;   
 
           arrayPoint.Add(point);   
       }                             
     }
 
     void draw(Surface surface)
     {
      Iterator<Point> i { arrayPoint };
      Point n0;
      // 返回圆周上的点
      returnRound();
      //画点
      i.Next();
      n0 = i.data;
      do
      {
         Point n1 = i.data;
         surface.DrawLine(n0.x,n0.y,n1.x,n1.y);
         n0 = n1;
      } while(i.Next()); 
 
      };
 
 
 
     ~Ellipse()
     {
     }; 
 
 
}
 
 
class Form1 : Window
{
   text = "Form1";
   background = activeBorder;
   borderStyle = sizable;
   hasMaximize = true;
   hasMinimize = true;
   hasClose = true;
   size = { 576, 432 };
 
   Ellipse ellipse{};
   void OnRedraw(Surface surface)
   {
      surface.SetForeground(blue);
      ellipse.Origin = {200,200};
      ellipse.Ra = 80;
      ellipse.Rb = 50;
      //ellipse.setStep(100);
      ellipse.draw(surface);
 
   }
 
}
 
Form1 form1 {};