You have to override OnPaint.
I tried doing this:
using System;
using System.Collections.Generic;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace testnamespace
{
public class MainWindow : Form
{
public static int a = 5 ;
public MainWindow()
{
this.SetStyle( ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer | ControlStyles.Opaque, true ) ;
}
public void Render()
{
// NOT DOUBLE BUFFERED! because
// its not in OnPaint.
Graphics g = Graphics.FromHwnd( this.Handle ) ;
g.Clear( Color.White ) ;
a++;
g.DrawLine( new Pen( Color.Blue, 5 ), new Point( 5, 5 ), new Point( a, 500 ) );
}
protected override void OnPaint( PaintEventArgs e )
{
// THIS IS double buffered
Graphics g = e.Graphics;
g.Clear( Color.White );
a++;
g.DrawLine( new Pen( Color.Blue, 5 ), new Point( 5, 5 ), new Point( a, 500 ) );
this.Invalidate();
//base.OnPaint( e );
}
static void Main()
{
// why not to use while(Created){FullRender();Application.DoEvents();}
//http://blogs.msdn.com/tmiller/archive/2003/11/07/57524.aspx
// Also here are records of people burned by it (scroll to bottom)
//http://msdn.microsoft.com/en-us/library/system.windows.forms.application.doevents.aspx
// alternative approaches to DoEvents loop
//http://blogs.msdn.com/tmiller/archive/2003/11/24/57532.aspx
// Using traditional PeekMessage() loop
// Create-up a window.
MainWindow mw = new MainWindow();
mw.Show();
// (style init stuff is in its constructor)
Win32.NativeMessage msg = new Win32.NativeMessage() ;
Dictionary dic = EnumHelper.ReverseEnumLookup();
while( true )
{
if( !mw.Created )
{
// Need this here for the application to shutdown gracefully.
break ;
}
if( Win32.PeekMessage( out msg, mw.Handle, 0, 0, (uint)Win32.PM.REMOVE ) )
{
int msgId = (int)msg.message ;
Console.WriteLine("MESSAGE!! " + msgId ) ;
if( dic.ContainsKey( msgId ) )
Console.WriteLine( "That's " + dic[msgId] ) ;
else
Console.WriteLine( "Unknown message!");
if( msg.message == (uint)Win32.WindowsMessage.WM_QUIT )
{
Console.WriteLine("QUITTING...");
break ;
}
else
{
Win32.TranslateMessage( ref msg ) ;
Win32.DispatchMessage ( ref msg ) ;
}
}
else
{
// Run the game simulation
// Render current state
mw.Render();
System.Threading.Thread.Sleep( 2 );
}
}
Application.Exit();
}
}
}
But windows won’t double buffer anything you draw unless its in the OnPaint method.
