using GLib using Gtk using GL using GLU public class Sample GLib Objec

using GLib;
using Gtk;
using GL;
using GLU;

public class Sample : GLib.Object
{
	static GLfloat[] light_diffuse;
	static GLfloat[] light_position;
	
	private static void realize (Widget widget)
	{
		Gdk.GL.Context glcontext = Gtk.GL.GtkWidgetExtension.get_gl_context (widget);
		Gdk.GL.Drawable gldrawable = Gtk.GL.GtkWidgetExtension.get_gl_drawable (widget);
		
		Quadric qobj;
		
		if (!(bool)gldrawable.gl_begin (glcontext))
			return;
			
		qobj = new Quadric ();
		qobj.QuadricDrawStyle (GLU.Consts.FILL);
		GL.NewList (1, GL.Consts.COMPILE);
		qobj.Sphere (1.0f, 20, 30);
		GL.EndList ();
		
		GL.Lightfv (GL.Consts.LIGHT0, GL.Consts.DIFFUSE, light_diffuse);
		GL.Lightfv (GL.Consts.LIGHT0, GL.Consts.POSITION, light_position);
		GL.Enable (GL.Consts.LIGHTING);
		GL.Enable (GL.Consts.LIGHT0);
		GL.Enable (GL.Consts.DEPTH_TEST);

		GL.ClearColor (1.0f, 1.0f, 1.0f, 1.0f);
		GL.ClearDepth (1.0f);

		GL.Viewport (0, 0, (GLsizei)widget.allocation.width, (GLsizei)widget.allocation.height);

		GL.MatrixMode (GL.Consts.PROJECTION);
		GL.LoadIdentity ();
		GLU.Perspective (40.0f, 1.0f, 1.0f, 10.0f);

		GL.MatrixMode (GL.Consts.MODELVIEW);
		GL.LoadIdentity ();
		GLU.LookAt (0.0f, 0.0f, 3.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
		GL.Translatef (0.0f, 0.0f, -3.0f);

		gldrawable.gl_end ();
	}
	
	private static bool configure_event (Widget widget, Gdk.Event event)
	{
		Gdk.GL.Context glcontext = Gtk.GL.GtkWidgetExtension.get_gl_context (widget);
		Gdk.GL.Drawable gldrawable = Gtk.GL.GtkWidgetExtension.get_gl_drawable (widget);

		if (!(bool)gldrawable.gl_begin (glcontext))
    		return false;

		GL.Viewport (0, 0, (GLsizei)widget.allocation.width, (GLsizei)widget.allocation.height);

		gldrawable.gl_end ();
		return true;
	}

	private static bool expose_event (Widget widget, Gdk.Event event)
	{
		Gdk.GL.Context glcontext = Gtk.GL.GtkWidgetExtension.get_gl_context (widget);
		Gdk.GL.Drawable gldrawable = Gtk.GL.GtkWidgetExtension.get_gl_drawable (widget);

		if (!(bool)gldrawable.gl_begin (glcontext))
			return false;

		GL.Clear (GL.Consts.COLOR_BUFFER_BIT | GL.Consts.DEPTH_BUFFER_BIT);

		GL.CallList (1);

		if (gldrawable.is_double_buffered ())
			gldrawable.swap_buffers ();
		else
			GL.Flush ();

		gldrawable.gl_end ();
		return true;
	}

	public static void main (string[] args)
	{
		Gdk.GL.Config glconfig;
		int major, minor;
		
		Window window;
		VBox vbox;
		DrawingArea drawing_area;
		Button button;
		
		Gtk.init (ref args);
		Gtk.GL.init (ref args);

		Gdk.GL.query_version (out major, out minor);
		print ("\nOpenGL extension version - %d.%d\n", major, minor);

		glconfig = new Gdk.GL.Config.by_mode (Gdk.GL.ConfigMode.RGB | Gdk.GL.ConfigMode.DEPTH | Gdk.GL.ConfigMode.DOUBLE);
		if (glconfig == null)
		{
			print ("*** Cannot find the double-buffered visual.\n");
			print ("*** Trying single-buffered visual.\n");
			
			glconfig = new Gdk.GL.Config.by_mode (Gdk.GL.ConfigMode.RGB | Gdk.GL.ConfigMode.DEPTH);
			if (glconfig == null)
			{
				print ("*** No appropriate OpenGL-capable visual found.\n");
				return;
			}
		}
		
		window = new Window (Gtk.WindowType.TOPLEVEL);
		window.title = "simple";
		
		window.set_reallocate_redraws (true);
		
		window.destroy += Gtk.main_quit;
		
		vbox = new VBox (false, 0);
		window.add (vbox);
		vbox.show ();
		
		light_diffuse = new GLfloat[] { 1.0f, 0.0f, 0.0f, 1.0f };
		light_position = new GLfloat[] { 1.0f, 1.0f, 1.0f, 0.0f };

		drawing_area = new DrawingArea ();
		drawing_area.set_size_request (200, 200);
		
		Gtk.GL.GtkWidgetExtension.set_gl_capability (drawing_area, glconfig, null, true, Gdk.GL.RenderType.RGBA_TYPE);
		
		drawing_area.realize += realize;
		drawing_area.configure_event += configure_event;
		drawing_area.expose_event += expose_event;
		
		vbox.pack_start (drawing_area, true, true, 0);
		
		drawing_area.show ();
		
		button = new Button.with_label ("Quit");
		button.clicked += Gtk.main_quit;
		
		vbox.pack_start (button, false, false, 0);
		button.show ();
		
		window.show ();
		
		Gtk.main ();
	}
}