Csharp/C Sharp/2D Graphics/Region

Create a Region whose boundary is the GraphicsPath

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      GraphicsPath gp = new GraphicsPath();
      // Create an open figure
      gp.AddLine(10, 10, 10, 50);
      gp.AddLine(10, 50, 50, 50);
      // Start a new figure
      gp.StartFigure();
      gp.AddLine(60, 10, 60, 50);
      gp.AddLine(60, 50, 100, 50);
      gp.CloseFigure();
      gp.AddEllipse(new Rectangle(110, 10, 40, 40));
      // Create a Region whose boundary is the above GraphicsPath 
      Region reg = new Region(gp);
      g.FillRegion(Brushes.Green, reg);
      reg.Dispose();
      gp.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Fill a Region

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      GraphicsPath gp = new GraphicsPath();
      gp.AddLine(10, 10, 10, 50);
      gp.AddBezier(10, 50, 120, 55, 25, 70, 30, 70);
      gp.AddLine(30, 70, 60, 70);
      gp.AddBezier(60, 70, 305, 70, 90, 55, 90, 50);
      gp.AddLine(90, 50, 90, 30);
      gp.StartFigure();
      gp.AddLine(60, 110, 40, 160);
      gp.AddLine(40, 160, 60, 180);
      // Create a Region whose boundary is the above GraphicsPath 
      Region reg = new Region(gp);
      g.FillRegion(Brushes.Green, reg);
      reg.Dispose();
      gp.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Fill region

using System;
using System.Drawing;
using System.Collections;
using System.ruponentModel;
using System.Windows.Forms;
using System.Data;
using System.Drawing.Drawing2D;

public class Form1 : System.Windows.Forms.Form
{
  private System.ruponentModel.Container components = null;
  public Form1()
  {
    InitializeComponent();
  }
  protected override void Dispose( bool disposing )
  {
    if( disposing )
    {
      if (components != null) 
      {
        components.Dispose();
      }
    }
    base.Dispose( disposing );
  }
    protected override void OnPaint ( PaintEventArgs e) {
      Rectangle r1 = new Rectangle(10, 10, 50, 50);
      Rectangle r2 = new Rectangle(40, 40, 50, 50);
      Region r = new Region(r1);
      r.Union(r2);
      GraphicsPath path = new GraphicsPath(new Point[] {new Point(45, 45),
                                                        new Point(145, 55),
                                                        new Point(200, 150),
                                                        new Point(75, 150),
                                                        new Point(45, 45)
                                                       }, new byte[] {  (byte)PathPointType.Start,
                                                                        (byte)PathPointType.Bezier,
                                                                        (byte)PathPointType.Bezier,
                                                                        (byte)PathPointType.Bezier,
                                                                        (byte)PathPointType.Line
                                                                     });
      r.Union(path);
      e.Graphics.FillRegion(Brushes.Blue, r);
    }
   private void InitializeComponent() {
      this.ruponents = new System.ruponentModel.Container();
      this.Size = new System.Drawing.Size(300,300);
      this.Text = "Form1";
    }
    static void Main() {
    Application.Run(new Form1());
  }
}

Get Clipping region painted

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      String s = "Create the necessary objects to draw the text string";
      Font f = new Font("Times New Roman", 12);
      SizeF sf = g.MeasureString(s, f, 100);
      RectangleF rf = new RectangleF(10, 10, sf.Width, sf.Height);
      g.DrawString(s, f, Brushes.Black, rf);
      f.Dispose();
      Console.WriteLine("Clipping region painted: " + e.ClipRectangle);
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Get repainted regions

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      SizeF sizeF = g.MeasureString("AA", this.Font);
      StringFormat sf = new StringFormat();
      sf.LineAlignment = StringAlignment.Center;
      // Set properties of the grid
      int cellHeight = (int)sizeF.Height + 200;
      int cellWidth = 200;
      int nbrColumns = 50;
      int nbrRows = 50;
      // Output general info to console
      Console.WriteLine("-------------------------------------------");
      Console.WriteLine("e.ClipRectangle = " + e.ClipRectangle);
      Console.WriteLine("The following cells need to be redrawn " +
                "(in whole or in part):");
      // Draw the cells and the output to console
      for (int row = 0; row < nbrRows; ++row)
      {
        for (int col = 0; col < nbrColumns; ++col)
        {
          Point cellLocation = new Point(col * cellWidth,
                             row * cellHeight);
          Rectangle cellRect = new Rectangle(cellLocation.X,
                             cellLocation.Y,
                             cellWidth, cellHeight);
          if (cellRect.IntersectsWith(e.ClipRectangle))
          {
            Console.WriteLine("Row:{0} Col:{1}", row, col);
            g.FillRectangle(Brushes.White, cellRect);
            g.DrawRectangle(Pens.Black, cellRect);
            String s = String.Format("{0},{1}", col, row);
            g.DrawString(s, this.Font, Brushes.Black, cellRect, sf);
          }
        }
      }
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Is a point visible to a Region

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region r = new Region(new Rectangle(30, 30, 30, 60));
      r.Exclude(new Rectangle(40, 40, 10, 10));
      g.FillRegion(Brushes.Orange, r);
      PointF pf = new PointF(35.0f, 30.0f);
      Console.WriteLine((r.IsVisible(pf) ? " - includes"
                         : " - excludes")
                + " the point (35.0, 50.0)");
      r.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Is Region Empty

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region r = new Region(new Rectangle(30, 30, 30, 60));
      r.Exclude(new Rectangle(40, 40, 10, 10));
      g.FillRegion(Brushes.Orange, r);
      Console.WriteLine(r.IsEmpty(g) ? " - is empty"
                       : " - is non-empty");
      r.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Is Region finite

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region r = new Region(new Rectangle(30, 30, 30, 60));
      r.Exclude(new Rectangle(40, 40, 10, 10));
      g.FillRegion(Brushes.Orange, r);
      Console.WriteLine(r.IsInfinite(g) ? " - is infinite"
                        : " - is finite");
      r.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Is this Rectangle visible to the Region

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region r = new Region(new Rectangle(30, 30, 30, 60));
      r.Exclude(new Rectangle(40, 40, 10, 10));
      g.FillRegion(Brushes.Orange, r);
      Rectangle rect = new Rectangle(25, 65, 5, 5);
      g.DrawRectangle(Pens.Black, rect);
      Console.WriteLine((r.IsVisible(rect) ? " - is visible"
                         : " - is invisible")
                + " in the rectangle shown");
      r.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Region Clips

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Rectangle rect = new Rectangle(10, 10, 80, 80);
      g.DrawRectangle(Pens.Black, rect);
      g.SetClip(rect);
      g.FillEllipse(Brushes.Blue, 20, 20, 100, 100);
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Region clips a text path

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      GraphicsPath gp = new GraphicsPath();
      gp.AddString("www.nfex.ru", new FontFamily("Times New Roman"),
            (int)(FontStyle.Bold | FontStyle.Italic),
            144, new Point(5, 5), StringFormat.GenericTypographic);
      g.SetClip(gp);
      g.DrawImage(new Bitmap("winter.jpg"), this.ClientRectangle);
      gp.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Region Excludes

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region r = new Region(new Rectangle(30, 30, 30, 60));
      r.Exclude(new Rectangle(40, 40, 10, 10));
      g.FillRegion(Brushes.Orange, r);
      r.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Region Unions

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);
      Region reg = new Region();
      reg.MakeEmpty();
      GraphicsPath gp = new GraphicsPath();
      gp.AddEllipse(10, 10, 50, 50);
      reg.Union(gp);
      gp.Reset();
      gp.AddLine(40, 40, 70, 10);
      gp.AddLine(70, 10, 140, 140);
      gp.CloseFigure();
      reg.Union(gp);
      reg.Union(new Rectangle(40, 50, 60, 60));
      // Set the clipping region
      g.SetClip(reg, CombineMode.Replace);
      g.FillRectangle(Brushes.Green, this.ClientRectangle);
      gp.Dispose();
      reg.Dispose();
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }