الگوریتم رسم خط در سی شارپ

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   protected void linebrace( int Xa,int Ya, int Xb , int Yb)
        {

 Bitmap bt;
             bt = new Bitmap(this.Width, this.Height);
            int p,X,Y,xEnd;
            int dx = System.Math. Abs(Xa-Xb); // فاصله ی x
            int dy = System.Math.Abs(Ya - Yb); //فاصله ی y

            p = 2 + dy - dx;
 
           
            if (Xa > Xb)
            {
                X = Xb;
                Y = Yb;
                xEnd = Xa;

            }
            else
            {
                X = Xa;
                Y = Ya;
                xEnd = Xb;
            }
            while(X < xEnd)
            {
                try
                {
                    bt.SetPixel(X, Y, Color.Blue);
                    X++;
                    if (p < 0)
                        p = p + 2 * X * dy;
                    else
                    {
                        Y++;
                        p = p + 2 * Math.Abs (dy - dx);

                    }
                }
                catch { MessageBox.Show(" An Error Occured"); break; }

            }// End While


        }