context: 
  #region ================== Copyright (c) 2007 Pascal vd Heiden
  
  /*
   * Copyright (c) 2007 Pascal vd Heiden, www.codeimp.com
   * This program is released under GNU General Public License
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   */
  
  #endregion
  
  #region ================== Namespaces
  
  using System;
  using System.Collections;
  using System.Collections.Generic;
  using System.Globalization;
  using System.Text;
  using System.Windows.Forms;
  using System.IO;
  using System.Reflection;
  using CodeImp.DoomBuilder.Windows;
  using CodeImp.DoomBuilder.IO;
  using CodeImp.DoomBuilder.Map;
  using CodeImp.DoomBuilder.Rendering;
  using CodeImp.DoomBuilder.Geometry;
  using CodeImp.DoomBuilder.Editing;
  using System.Drawing;
  using CodeImp.DoomBuilder.Actions;
  using CodeImp.DoomBuilder.Types;
  using CodeImp.DoomBuilder.BuilderModes.Interface;
  
  #endregion
  
  namespace CodeImp.DoomBuilder.BuilderModes
  {
  	[EditMode(DisplayName = "Sectors Mode",
  			  SwitchAction = "sectorsmode",		// Action name used to switch to this mode
  		      ButtonImage = "SectorsMode.png",	// Image resource name for the button
  			  ButtonOrder = int.MinValue + 200,	// Position of the button (lower is more to the left)
  			  ButtonGroup = "000_editing",
  			  UseByDefault = true,
  			  SafeStartMode = true)]
  
  	public class SectorsMode : BaseClassicMode
  	{
  		#region ================== Constants
  
  		#endregion
  
  		#region ================== Variables
  
  		// Highlighted item
  		protected Sector highlighted;
  		private Association highlightasso = new Association();
          public const int NUM_PORTAL_ASSOCIATIONS = 2;
          private Association[] portalasso = new Association[NUM_PORTAL_ASSOCIATIONS];
  
          // Interface
          protected bool editpressed;
  
  		// Labels
  		private Dictionary<Sector, TextLabel[]> labels;
  		
  		#endregion
  
  		#region ================== Properties
  
  		public override object HighlightedObject { get { return highlighted; } }
  
  		#endregion
  
  		#region ================== Constructor / Disposer
  
  		// Constructor
  		public SectorsMode()
  		{
  		}
  
  		// Disposer
  		public override void Dispose()
  		{
  			// Not already disposed?
  			if(!isdisposed)
  			{
  				// Dispose old labels
  				foreach(KeyValuePair<Sector, TextLabel[]> lbl in labels)
  					foreach(TextLabel l in lbl.Value) l.Dispose();
  
  				// Dispose base
  				base.Dispose();
  			}
  		}
  
  		#endregion
  
  		#region ================== Methods
  
  		// This makes a CRC for the selection
  		public int CreateSelectionCRC()
  		{
  			CRC crc = new CRC();
  			ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  			crc.Add(orderedselection.Count);
  			foreach(Sector s in orderedselection)
  			{
  				crc.Add(s.FixedIndex);
  			}
  			return (int)(crc.Value & 0xFFFFFFFF);
  		}
  
  		// This sets up new labels
  		private void SetupLabels()
  		{
  			if(labels != null)
  			{
  				// Dispose old labels
  				foreach(KeyValuePair<Sector, TextLabel[]> lbl in labels)
  					foreach(TextLabel l in lbl.Value) l.Dispose();
  			}
  
  			// Make text labels for sectors
  			labels = new Dictionary<Sector, TextLabel[]>(General.Map.Map.Sectors.Count);
  			foreach(Sector s in General.Map.Map.Sectors)
  			{
  				// Setup labels
  				TextLabel[] labelarray = new TextLabel[s.Labels.Count];
  				for(int i = 0; i < s.Labels.Count; i++)
  				{
  					Vector2D v = s.Labels[i].position;
  					labelarray[i] = new TextLabel(20);
  					labelarray[i].TransformCoords = true;
  					labelarray[i].Rectangle = new RectangleF(v.x, v.y, 0.0f, 0.0f);
  					labelarray[i].AlignX = TextAlignmentX.Center;
  					labelarray[i].AlignY = TextAlignmentY.Middle;
  					labelarray[i].Scale = 14f;
  					labelarray[i].Color = General.Colors.Highlight.WithAlpha(255);
  					labelarray[i].Backcolor = General.Colors.Background.WithAlpha(255);
  				}
  				labels.Add(s, labelarray);
  			}
  		}
  
  		// This updates the overlay
  		private void UpdateOverlay()
  		{
  			if(renderer.StartOverlay(true))
  			{
  				if(BuilderPlug.Me.ViewSelectionNumbers)
  				{
  					// Go for all selected sectors
  					ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  					foreach(Sector s in orderedselection)
  					{
  						// Render labels
  						TextLabel[] labelarray = labels[s];
  						for(int i = 0; i < s.Labels.Count; i++)
  						{
  							TextLabel l = labelarray[i];
  
  							// Render only when enough space for the label to see
  							float requiredsize = (l.TextSize.Height / 2) / renderer.Scale;
  							if(requiredsize < s.Labels[i].radius) renderer.RenderText(l);
  						}
  					}
  				}
  				
  				renderer.Finish();
  			}
  		}
  		
  		// Support function for joining and merging sectors
  		private void JoinMergeSectors(bool removelines)
  		{
  			// Remove lines in betwen joining sectors?
  			if(removelines)
  			{
  				// Go for all selected linedefs
  				List<Linedef> selectedlines = new List<Linedef>(General.Map.Map.GetSelectedLinedefs(true));
  				foreach(Linedef ld in selectedlines)
  				{
  					// Front and back side?
  					if((ld.Front != null) && (ld.Back != null))
  					{
  						// Both a selected sector, but not the same?
  						if(ld.Front.Sector.Selected && ld.Back.Sector.Selected &&
  						   (ld.Front.Sector != ld.Back.Sector))
  						{
  							// Remove this line
  							ld.Dispose();
  						}
  					}
  				}
  			}
  
  			// Find the first sector that is not disposed
  			List<Sector> orderedselection = new List<Sector>(General.Map.Map.GetSelectedSectors(true));
  			Sector first = null;
  			foreach(Sector s in orderedselection)
  				if(!s.IsDisposed) { first = s; break; }
  			
  			// Join all selected sectors with the first
  			for(int i = 0; i < orderedselection.Count; i++)
  				if((orderedselection[i] != first) && !orderedselection[i].IsDisposed)
  					orderedselection[i].Join(first);
  
  			// Clear selection
  			General.Map.Map.ClearAllSelected();
  			
  			// Update
  			General.Map.Map.Update();
  			
  			// Make text labels for sectors
  			SetupLabels();
  			UpdateSelectedLabels();
  		}
  
  		// This highlights a new item
  		protected void Highlight(Sector s)
  		{
  			bool completeredraw = false;
  
  			// Often we can get away by simply undrawing the previous
  			// highlight and drawing the new highlight. But if associations
  			// are or were drawn we need to redraw the entire display.
  
  			// Previous association highlights something?
  			if((highlighted != null) && (highlighted.Tag > 0)) completeredraw = true;
  
              // Set highlight association
              if (s != null)
              {
                  highlightasso.Set(s.Tag, UniversalType.SectorTag);
                  // portals
                  if (General.Map.Config.UDMF)
                  {
                      // floor
                      if (portalasso[0].type != 0)
                      {
                          completeredraw = true;
                      }
                      portalasso[0].Set(0, 0);
                      if (s != null
                          && s.Fields.ContainsKey("portalfloor")
                          && s.Fields["portalfloor"].Type == (int)UniversalType.PortalTag)
                      {
  
                         portalasso[0].Set(Math.Abs((int)s.Fields["portalfloor"].Value), (int)UniversalType.PortalTag);
                      }
                      if (portalasso[0].type != 0)
                      {
                          completeredraw = true;
                      }
  
                      // ceil
                      if (portalasso[1].type != 0)
                      {
                          completeredraw = true;
                      }
                      portalasso[1].Set(0, 0);
                      if (s != null
                          && s.Fields.ContainsKey("portalceiling")
                          && s.Fields["portalceiling"].Type == (int)UniversalType.PortalTag)
                      {
  
                          portalasso[1].Set(Math.Abs((int)s.Fields["portalceiling"].Value), (int)UniversalType.PortalTag);
                      }
                      if (portalasso[1].type != 0)
                      {
                          completeredraw = true;
                      }
                  } // portals
              }
              else
              {
                  highlightasso.Set(0, 0);
                  for (int i = 0; i < NUM_PORTAL_ASSOCIATIONS; i++)
                  {
                      if (portalasso[i].type != 0)
                      {
                          completeredraw = true;
                      }
                      portalasso[i].Set(0, 0);
                  }
              }
  
              // New association highlights something?
              if ((s != null) && (s.Tag > 0)) completeredraw = true;
  
  			// Change label color
  			if((highlighted != null) && !highlighted.IsDisposed)
  			{
  				TextLabel[] labelarray = labels[highlighted];
  				foreach(TextLabel l in labelarray) l.Color = General.Colors.Selection;
  			}
  			
  			// Change label color
  			if((s != null) && !s.IsDisposed)
  			{
  				TextLabel[] labelarray = labels[s];
  				foreach(TextLabel l in labelarray) l.Color = General.Colors.Highlight;
  			}
  			
  			// If we're changing associations, then we
  			// need to redraw the entire display
  			if(completeredraw)
  			{
  				// Set new highlight and redraw completely
  				highlighted = s;
  				General.Interface.RedrawDisplay();
  			}
  			else
  			{
  				// Update display
  				if(renderer.StartPlotter(false))
  				{
  					// Undraw previous highlight
  					if((highlighted != null) && !highlighted.IsDisposed)
  						renderer.PlotSector(highlighted);
  					
  					/*
  					// Undraw highlighted things
  					if(highlighted != null)
  						foreach(Thing t in highlighted.Things)
  							renderer.RenderThing(t, renderer.DetermineThingColor(t));
  					*/
  
  					// Set new highlight
  					highlighted = s;
  
  					// Render highlighted item
  					if((highlighted != null) && !highlighted.IsDisposed)
  						renderer.PlotSector(highlighted, General.Colors.Highlight);
  					
  					/*
  					// Render highlighted things
  					if(highlighted != null)
  						foreach(Thing t in highlighted.Things)
  							renderer.RenderThing(t, General.Colors.Highlight);
  					*/
  
  					// Done
  					renderer.Finish();
  				}
  				
  				UpdateOverlay();
  				renderer.Present();
  			}
  
  			// Show highlight info
  			if((highlighted != null) && !highlighted.IsDisposed)
  				General.Interface.ShowSectorInfo(highlighted);
  			else
  				General.Interface.HideInfo();
  		}
  
  		// This selectes or deselects a sector
  		protected void SelectSector(Sector s, bool selectstate, bool update)
  		{
  			bool selectionchanged = false;
  
  			if(!s.IsDisposed)
  			{
  				// Select the sector?
  				if(selectstate && !s.Selected)
  				{
  					s.Selected = true;
  					selectionchanged = true;
  					
  					// Setup labels
  					ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  					TextLabel[] labelarray = labels[s];
  					foreach(TextLabel l in labelarray)
  					{
  						l.Text = orderedselection.Count.ToString();
  						l.Color = General.Colors.Selection;
  					}
  				}
  				// Deselect the sector?
  				else if(!selectstate && s.Selected)
  				{
  					s.Selected = false;
  					selectionchanged = true;
  
  					// Clear labels
  					TextLabel[] labelarray = labels[s];
  					foreach(TextLabel l in labelarray) l.Text = "";
  
  					// Update all other labels
  					UpdateSelectedLabels();
  				}
  
  				// Selection changed?
  				if(selectionchanged)
  				{
  					// Make update lines selection
  					foreach(Sidedef sd in s.Sidedefs)
  					{
  						bool front, back;
  						if(sd.Line.Front != null) front = sd.Line.Front.Sector.Selected; else front = false;
  						if(sd.Line.Back != null) back = sd.Line.Back.Sector.Selected; else back = false;
  						sd.Line.Selected = front | back;
  					}
  				}
  
  				if(update)
  				{
  					UpdateOverlay();
  					renderer.Present();
  				}
  			}
  		}
  
  		// This updates labels from the selected sectors
  		private void UpdateSelectedLabels()
  		{
  			// Go for all labels in all selected sectors
  			ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  			int index = 0;
  			foreach(Sector s in orderedselection)
  			{
  				TextLabel[] labelarray = labels[s];
  				foreach(TextLabel l in labelarray)
  				{
  					// Make sure the text and color are right
  					int labelnum = index + 1;
  					l.Text = labelnum.ToString();
  					l.Color = General.Colors.Selection;
  				}
  				index++;
  			}
  		}
  
  		#endregion
  		
  		#region ================== Events
  
  		public override void OnHelp()
  		{
  			General.ShowHelp("e_sectors.html");
  		}
  
  		// Cancel mode
  		public override void OnCancel()
  		{
  			base.OnCancel();
  
  			// Return to this mode
  			General.Editing.ChangeMode(new SectorsMode());
  		}
  
  		// Mode engages
  		public override void OnEngage()
  		{
  			base.OnEngage();
  			renderer.SetPresentation(Presentation.Standard);
  
  			// Add toolbar buttons
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.CopyProperties);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.PasteProperties);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.SeparatorCopyPaste);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.ViewSelectionNumbers);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.SeparatorSectors1);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.MakeGradientBrightness);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.MakeGradientFloors);
  			General.Interface.AddButton(BuilderPlug.Me.MenusForm.MakeGradientCeilings);
  			
  			// Convert geometry selection to sectors only
  			General.Map.Map.ConvertSelection(SelectionType.Sectors);
  
  			// Make text labels for sectors
  			SetupLabels();
  			
  			// Update
  			UpdateSelectedLabels();
  			UpdateOverlay();
  		}
  		
  		// Mode disengages
  		public override void OnDisengage()
  		{
  			base.OnDisengage();
  
  			// Remove toolbar buttons
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.CopyProperties);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.PasteProperties);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.SeparatorCopyPaste);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.ViewSelectionNumbers);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.SeparatorSectors1);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.MakeGradientBrightness);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.MakeGradientFloors);
  			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.MakeGradientCeilings);
  			
  			// Keep only sectors selected
  			General.Map.Map.ClearSelectedLinedefs();
  			
  			// Going to EditSelectionMode?
  			if(General.Editing.NewMode is EditSelectionMode)
  			{
  				// Not pasting anything?
  				EditSelectionMode editmode = (General.Editing.NewMode as EditSelectionMode);
  				if(!editmode.Pasting)
  				{
  					// No selection made? But we have a highlight!
  					if((General.Map.Map.GetSelectedSectors(true).Count == 0) && (highlighted != null))
  					{
  						// Make the highlight the selection
  						SelectSector(highlighted, true, false);
  					}
  				}
  			}
  			
  			// Hide highlight info
  			General.Interface.HideInfo();
  		}
  
  		// This redraws the display
  		public override void OnRedrawDisplay()
  		{
  			renderer.RedrawSurface();
  			
  			// Render lines and vertices
  			if(renderer.StartPlotter(true))
  			{
  				renderer.PlotLinedefSet(General.Map.Map.Linedefs);
  				renderer.PlotVerticesSet(General.Map.Map.Vertices);
  				if((highlighted != null) && !highlighted.IsDisposed)
                  {
                      BuilderPlug.Me.PlotAssociations(renderer, portalasso[0]);
                      BuilderPlug.Me.PlotAssociations(renderer, portalasso[1]);
                      renderer.PlotSector(highlighted, General.Colors.Highlight);
  					BuilderPlug.Me.PlotReverseAssociations(renderer, highlightasso);
                  }
  				renderer.Finish();
  			}
  
  			// Render things
  			if(renderer.StartThings(true))
  			{
  				renderer.RenderThingSet(General.Map.ThingsFilter.HiddenThings, Presentation.THINGS_HIDDEN_ALPHA);
  				renderer.RenderThingSet(General.Map.ThingsFilter.VisibleThings, 1.0f);
  				renderer.Finish();
  			}
  
  			// Render selection
  			if(renderer.StartOverlay(true))
  			{
  				if((highlighted != null) && !highlighted.IsDisposed) BuilderPlug.Me.RenderReverseAssociations(renderer, highlightasso);
  				if(selecting) RenderMultiSelection();
  				renderer.Finish();
  			}
  
  			// Render overlay
  			UpdateOverlay();
  			
  			renderer.Present();
  		}
  
  		// Selection
  		protected override void OnSelectBegin()
  		{
  			// Item highlighted?
  			if((highlighted != null) && !highlighted.IsDisposed)
  			{
  				// Flip selection
  				SelectSector(highlighted, !highlighted.Selected, true);
  
  				// Update display
  				if(renderer.StartPlotter(false))
  				{
  					// Redraw highlight to show selection
  					renderer.PlotSector(highlighted);
  					renderer.Finish();
  					renderer.Present();
  				}
  			}
  			else
  			{
  				// Start making a selection
  				StartMultiSelection();
  			}
  
  			base.OnSelectBegin();
  		}
  
  		// End selection
  		protected override void OnSelectEnd()
  		{
  			// Not stopping from multiselection?
  			if(!selecting)
  			{
  				// Item highlighted?
  				if((highlighted != null) && !highlighted.IsDisposed)
  				{
  					// Update display
  					if(renderer.StartPlotter(false))
  					{
  						// Render highlighted item
  						renderer.PlotSector(highlighted, General.Colors.Highlight);
  						renderer.Finish();
  						renderer.Present();
  					}
  
  					// Update overlay
  					TextLabel[] labelarray = labels[highlighted];
  					foreach(TextLabel l in labelarray) l.Color = General.Colors.Highlight;
  					UpdateOverlay();
  					renderer.Present();
  				}
  			}
  
  			base.OnSelectEnd();
  		}
  
  		// Start editing
  		protected override void OnEditBegin()
  		{
  			// Item highlighted?
  			if((highlighted != null) && !highlighted.IsDisposed)
  			{
  				// Edit pressed in this mode
  				editpressed = true;
  
  				// Highlighted item not selected?
  				if(!highlighted.Selected && (BuilderPlug.Me.AutoClearSelection || (General.Map.Map.SelectedSectorsCount == 0)))
  				{
  					// Make this the only selection
  					General.Map.Map.ClearSelectedSectors();
  					General.Map.Map.ClearSelectedLinedefs();
  					SelectSector(highlighted, true, false);
  					General.Interface.RedrawDisplay();
  				}
  
  				// Update display
  				if(renderer.StartPlotter(false))
  				{
  					// Redraw highlight to show selection
  					renderer.PlotSector(highlighted);
  					renderer.Finish();
  					renderer.Present();
  				}
  			}
  			else
  			{
  				// Start drawing mode
  				DrawGeometryMode drawmode = new DrawGeometryMode();
  				bool snaptogrid = General.Interface.ShiftState ^ General.Interface.SnapToGrid;
  				bool snaptonearest = General.Interface.CtrlState ^ General.Interface.AutoMerge;
  				DrawnVertex v = DrawGeometryMode.GetCurrentPosition(mousemappos, snaptonearest, snaptogrid, renderer, new List<DrawnVertex>());
  				
  				if(drawmode.DrawPointAt(v))
  					General.Editing.ChangeMode(drawmode);
  				else
  					General.Interface.DisplayStatus(StatusType.Warning, "Failed to draw point: outside of map boundaries.");
  			}
  			
  			base.OnEditBegin();
  		}
  
  		// Done editing
  		protected override void OnEditEnd()
  		{
  			// Edit pressed in this mode?
  			if(editpressed)
  			{
  				// Anything selected?
  				ICollection<Sector> selected = General.Map.Map.GetSelectedSectors(true);
  				if(selected.Count > 0)
  				{
  					if(General.Interface.IsActiveWindow)
  					{
  						// Show sector edit dialog
  						General.Interface.ShowEditSectors(selected);
  						General.Map.Map.Update();
  						
  						// When a single sector was selected, deselect it now
  						if(selected.Count == 1)
  						{
  							General.Map.Map.ClearSelectedSectors();
  							General.Map.Map.ClearSelectedLinedefs();
  						}
  
  						// Update entire display
  						General.Interface.RedrawDisplay();
  					}
  				}
  			}
  
  			editpressed = false;
  			base.OnEditEnd();
  		}
  		
  		// Mouse moves
  		public override void OnMouseMove(MouseEventArgs e)
  		{
  			base.OnMouseMove(e);
  
  			// Not holding any buttons?
  			if(e.Button == MouseButtons.None)
  			{
  				// Find the nearest linedef within highlight range
  				Linedef l = General.Map.Map.NearestLinedef(mousemappos);
  				if(l != null)
  				{
  					// Check on which side of the linedef the mouse is
  					float side = l.SideOfLine(mousemappos);
  					if(side > 0)
  					{
  						// Is there a sidedef here?
  						if(l.Back != null)
  						{
  							// Highlight if not the same
  							if(l.Back.Sector != highlighted) Highlight(l.Back.Sector);
  						}
  						else
  						{
  							// Highlight nothing
  							if(highlighted != null) Highlight(null);
  						}
  					}
  					else
  					{
  						// Is there a sidedef here?
  						if(l.Front != null)
  						{
  							// Highlight if not the same
  							if(l.Front.Sector != highlighted) Highlight(l.Front.Sector);
  						}
  						else
  						{
  							// Highlight nothing
  							if(highlighted != null) Highlight(null);
  						}
  					}
  				}
  				else
  				{
  					// Highlight nothing
  					if(highlighted != null) Highlight(null);
  				}
  			}
  		}
  
  		// Mouse leaves
  		public override void OnMouseLeave(EventArgs e)
  		{
  			base.OnMouseLeave(e);
  
  			// Highlight nothing
  			Highlight(null);
  		}
  
  		// Mouse wants to drag
  		protected override void OnDragStart(MouseEventArgs e)
  		{
  			base.OnDragStart(e);
  
  			// Edit button used?
  			if(General.Actions.CheckActionActive(null, "classicedit"))
  			{
  				// Anything highlighted?
  				if((highlighted != null) && !highlighted.IsDisposed)
  				{
  					// Highlighted item not selected?
  					if(!highlighted.Selected)
  					{
  						// Select only this sector for dragging
  						General.Map.Map.ClearSelectedSectors();
  						SelectSector(highlighted, true, true);
  					}
  
  					// Start dragging the selection
  					General.Editing.ChangeMode(new DragSectorsMode(mousedownmappos));
  				}
  			}
  		}
  
  		// This is called wheh selection ends
  		protected override void OnEndMultiSelection()
  		{
  			bool selectionvolume = ((Math.Abs(base.selectionrect.Width) > 0.1f) && (Math.Abs(base.selectionrect.Height) > 0.1f));
  
  			if(BuilderPlug.Me.AutoClearSelection && !selectionvolume)
  			{
  				General.Map.Map.ClearSelectedLinedefs();
  				General.Map.Map.ClearSelectedSectors();
  			}
  
  			if(selectionvolume)
  			{
  				if(General.Interface.ShiftState ^ BuilderPlug.Me.AdditiveSelect)
  				{
  					// Go for all lines
  					foreach(Linedef l in General.Map.Map.Linedefs)
  					{
  						l.Selected |= ((l.Start.Position.x >= selectionrect.Left) &&
  									   (l.Start.Position.y >= selectionrect.Top) &&
  									   (l.Start.Position.x <= selectionrect.Right) &&
  									   (l.Start.Position.y <= selectionrect.Bottom) &&
  									   (l.End.Position.x >= selectionrect.Left) &&
  									   (l.End.Position.y >= selectionrect.Top) &&
  									   (l.End.Position.x <= selectionrect.Right) &&
  									   (l.End.Position.y <= selectionrect.Bottom));
  					}
  				}
  				else
  				{
  					// Go for all lines
  					foreach(Linedef l in General.Map.Map.Linedefs)
  					{
  						l.Selected = ((l.Start.Position.x >= selectionrect.Left) &&
  									  (l.Start.Position.y >= selectionrect.Top) &&
  									  (l.Start.Position.x <= selectionrect.Right) &&
  									  (l.Start.Position.y <= selectionrect.Bottom) &&
  									  (l.End.Position.x >= selectionrect.Left) &&
  									  (l.End.Position.y >= selectionrect.Top) &&
  									  (l.End.Position.x <= selectionrect.Right) &&
  									  (l.End.Position.y <= selectionrect.Bottom));
  					}
  				}
  				
  				// Go for all sectors
  				foreach(Sector s in General.Map.Map.Sectors)
  				{
  					// Go for all sidedefs
  					bool allselected = true;
  					foreach(Sidedef sd in s.Sidedefs)
  					{
  						if(!sd.Line.Selected)
  						{
  							allselected = false;
  							break;
  						}
  					}
  					
  					// Sector completely selected?
  					SelectSector(s, allselected, false);
  				}
  				
  				// Make sure all linedefs reflect selected sectors
  				foreach(Sidedef sd in General.Map.Map.Sidedefs)
  					if(!sd.Sector.Selected && ((sd.Other == null) || !sd.Other.Sector.Selected))
  						sd.Line.Selected = false;
  			}
  			
  			base.OnEndMultiSelection();
  			if(renderer.StartOverlay(true)) renderer.Finish();
  			General.Interface.RedrawDisplay();
  		}
  
  		// This is called when the selection is updated
  		protected override void OnUpdateMultiSelection()
  		{
  			base.OnUpdateMultiSelection();
  
  			// Render selection
  			if(renderer.StartOverlay(true))
  			{
  				RenderMultiSelection();
  				renderer.Finish();
  				renderer.Present();
  			}
  		}
  
  		// When copying
  		public override bool OnCopyBegin()
  		{
  			// No selection made? But we have a highlight!
  			if((General.Map.Map.GetSelectedSectors(true).Count == 0) && (highlighted != null))
  			{
  				// Make the highlight the selection
  				SelectSector(highlighted, true, true);
  			}
  
  			return base.OnCopyBegin();
  		}
  
  		// When undo is used
  		public override bool OnUndoBegin()
  		{
  			// Clear ordered selection
  			General.Map.Map.ClearAllSelected();
  
  			return base.OnUndoBegin();
  		}
  
  		// When undo is performed
  		public override void OnUndoEnd()
  		{
  			// Clear labels
  			SetupLabels();
  		}
  		
  		// When redo is used
  		public override bool OnRedoBegin()
  		{
  			// Clear ordered selection
  			General.Map.Map.ClearAllSelected();
  
  			return base.OnRedoBegin();
  		}
  
  		// When redo is performed
  		public override void OnRedoEnd()
  		{
  			// Clear labels
  			SetupLabels();
  		}
  		
  		#endregion
  
  		#region ================== Actions
  
  		// This copies the properties
  		[BeginAction("classiccopyproperties")]
  		public void CopyProperties()
  		{
  			// Determine source sectors
  			ICollection<Sector> sel = null;
  			if(General.Map.Map.SelectedSectorsCount > 0)
  				sel = General.Map.Map.GetSelectedSectors(true);
  			else if(highlighted != null)
  			{
  				sel = new List<Sector>();
  				sel.Add(highlighted);
  			}
  			
  			if(sel != null)
  			{
  				// Copy properties from first source sectors
  				BuilderPlug.Me.CopiedSectorProps = new SectorProperties(General.GetByIndex(sel, 0));
  				General.Interface.DisplayStatus(StatusType.Action, "Copied sector properties.");
  			}
  		}
  
  		// This pastes the properties
  		[BeginAction("classicpasteproperties")]
  		public void PasteProperties()
  		{
  			if(BuilderPlug.Me.CopiedSectorProps != null)
  			{
  				// Determine target sectors
  				ICollection<Sector> sel = null;
  				if(General.Map.Map.SelectedSectorsCount > 0)
  					sel = General.Map.Map.GetSelectedSectors(true);
  				else if(highlighted != null)
  				{
  					sel = new List<Sector>();
  					sel.Add(highlighted);
  				}
  				
  				if(sel != null)
  				{
  					// Apply properties to selection
  					General.Map.UndoRedo.CreateUndo("Paste sector properties");
  					foreach(Sector s in sel)
  					{
  						BuilderPlug.Me.CopiedSectorProps.Apply(s);
  						s.UpdateCeilingSurface();
  						s.UpdateFloorSurface();
  					}
  					General.Interface.DisplayStatus(StatusType.Action, "Pasted sector properties.");
  					
  					// Update and redraw
  					General.Map.IsChanged = true;
  					General.Interface.RefreshInfo();
  					General.Interface.RedrawDisplay();
  				}
  			}
  		}
  
  		// This creates a new vertex at the mouse position
  		[BeginAction("insertitem", BaseAction = true)]
  		public virtual void InsertVertexAction()
  		{
  			// Start drawing mode
  			DrawGeometryMode drawmode = new DrawGeometryMode();
  			if(mouseinside)
  			{
  				bool snaptogrid = General.Interface.ShiftState ^ General.Interface.SnapToGrid;
  				bool snaptonearest = General.Interface.CtrlState ^ General.Interface.AutoMerge;
  				DrawnVertex v = DrawGeometryMode.GetCurrentPosition(mousemappos, snaptonearest, snaptogrid, renderer, new List<DrawnVertex>());
  				drawmode.DrawPointAt(v);
  			}
  			General.Editing.ChangeMode(drawmode);
  		}
  
  		[BeginAction("makedoor")]
  		public void MakeDoor()
  		{
  			// Highlighted item not selected?
  			if((highlighted != null) && !highlighted.Selected)
  			{
  				// Make this the only selection
  				General.Map.Map.ClearSelectedSectors();
  				General.Map.Map.ClearSelectedLinedefs();
  				SelectSector(highlighted, true, false);
  				General.Interface.RedrawDisplay();
  			}
  			
  			// Anything selected?
  			ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  			if(orderedselection.Count > 0)
  			{
  				string doortex = "";
  				string tracktex = General.Map.Config.MakeDoorTrack;
  				string floortex = null;
  				string ceiltex = null;
  				bool resetoffsets = true;
  				
  				// Find ceiling and floor textures
  				foreach(Sector s in orderedselection)
  				{
  					if(floortex == null) floortex = s.FloorTexture; else if(floortex != s.FloorTexture) floortex = "";
  					if(ceiltex == null) ceiltex = s.CeilTexture; else if(ceiltex != s.CeilTexture) ceiltex = "";
  				}
  				
  				// Show the dialog
  				MakeDoorForm form = new MakeDoorForm();
  				if(form.Show(General.Interface, doortex, tracktex, ceiltex, floortex, resetoffsets) == DialogResult.OK)
  				{
  					doortex = form.DoorTexture;
  					tracktex = form.TrackTexture;
  					ceiltex = form.CeilingTexture;
  					floortex = form.FloorTexture;
  					resetoffsets = form.ResetOffsets;
  					
  					// Create undo
  					General.Map.UndoRedo.CreateUndo("Make door (" + doortex + ")");
  					General.Interface.DisplayStatus(StatusType.Action, "Created a " + doortex + " door.");
  					
  					// Go for all selected sectors
  					foreach(Sector s in orderedselection)
  					{
  						// Lower the ceiling down to the floor
  						s.CeilHeight = s.FloorHeight;
  
  						// Make a unique tag (not sure if we need it yet, depends on the args)
  						int tag = General.Map.Map.GetNewTag();
  
  						// Go for all it's sidedefs
  						foreach(Sidedef sd in s.Sidedefs)
  						{
  							// Singlesided?
  							if(sd.Other == null)
  							{
  								// Make this a doortrak
  								sd.SetTextureHigh("-");
  								sd.SetTextureMid(tracktex);
  								sd.SetTextureLow("-");
  
  								// Set upper/lower unpegged flags
  								sd.Line.SetFlag(General.Map.Config.UpperUnpeggedFlag, false);
  								sd.Line.SetFlag(General.Map.Config.LowerUnpeggedFlag, true);
  							}
  							else
  							{
  								// Set textures
  								if(floortex.Length > 0) s.SetFloorTexture(floortex);
  								if(ceiltex.Length > 0) s.SetCeilTexture(ceiltex);
  								if(doortex.Length > 0) sd.Other.SetTextureHigh(doortex);
  
  								// Set upper/lower unpegged flags
  								sd.Line.SetFlag(General.Map.Config.UpperUnpeggedFlag, false);
  								sd.Line.SetFlag(General.Map.Config.LowerUnpeggedFlag, false);
  								
  								// Get door linedef type from config
  								sd.Line.Action = General.Map.Config.MakeDoorAction;
  
  								// Set activation type
  								sd.Line.Activate = General.Map.Config.MakeDoorActivate;
  
  								// Set the flags
  								foreach(var flagpair in General.Map.Config.MakeDoorFlags)
  									sd.Line.SetFlag(flagpair.Key, flagpair.Value);
  
  								// Set the linedef args
  								for(int i = 0; i < Linedef.NUM_ARGS; i++)
  								{
  									// A -1 arg indicates that the arg must be set to the new sector tag
  									// and only in this case we set the tag on the sector, because only
  									// then we know for sure that we need a tag.
  									if(General.Map.Config.MakeDoorArgs[i] == -1)
  									{
  										sd.Line.Args[i] = tag;
  										s.Tag = tag;
  									}
  									else
  									{
  										sd.Line.Args[i] = General.Map.Config.MakeDoorArgs[i];
  									}
  								}
  
  								// Make sure the line is facing outwards
  								if(sd.IsFront)
  								{
  									sd.Line.FlipVertices();
  									sd.Line.FlipSidedefs();
  								}
  							}
  
  							// Reset the texture offsets if required
  							if (resetoffsets)
  							{
  								sd.OffsetX = 0;
  								sd.OffsetY = 0;
  
  								if (sd.Other != null)
  								{
  									sd.Other.OffsetX = 0;
  									sd.Other.OffsetY = 0;
  								}
  							}
  						}
  					}
  					
  					// When a single sector was selected, deselect it now
  					if(orderedselection.Count == 1)
  					{
  						orderedselection.Clear();
  						General.Map.Map.ClearSelectedSectors();
  						General.Map.Map.ClearSelectedLinedefs();
  					}
  				}
  				
  				// Done
  				form.Dispose();
  				General.Interface.RedrawDisplay();
  			}
  		}
  		
  		[BeginAction("deleteitem", BaseAction = true)]
  		public void DeleteItem()
  		{
  			// Make list of selected sectors
  			List<Sector> selected = new List<Sector>(General.Map.Map.GetSelectedSectors(true));
  			if((selected.Count == 0) && (highlighted != null) && !highlighted.IsDisposed) selected.Add(highlighted);
  
  			// Anything to do?
  			if(selected.Count > 0)
  			{
  				// Make undo
  				if(selected.Count > 1)
  				{
  					General.Map.UndoRedo.CreateUndo("Delete " + selected.Count + " sectors");
  					General.Interface.DisplayStatus(StatusType.Action, "Deleted " + selected.Count + " sectors.");
  				}
  				else
  				{
  					General.Map.UndoRedo.CreateUndo("Delete sector");
  					General.Interface.DisplayStatus(StatusType.Action, "Deleted sector.");
  				}
  
  				// Dispose selected sectors
  				foreach(Sector s in selected)
  				{
  					// Get all the linedefs
  					General.Map.Map.ClearMarkedLinedefs(false);
  					foreach(Sidedef sd in s.Sidedefs) sd.Line.Marked = true;
  					List<Linedef> lines = General.Map.Map.GetMarkedLinedefs(true);
  					
  					// Dispose the sector
  					s.Dispose();
  
  					// Check all the lines
  					for(int i = lines.Count - 1; i >= 0; i--)
  					{
  						// If the line has become orphaned, remove it
  						if((lines[i].Front == null) && (lines[i].Back == null))
  						{
  							// Remove line
  							lines[i].Dispose();
  						}
  						else
  						{
  							// If the line only has a back side left, flip the line and sides
  							if((lines[i].Front == null) && (lines[i].Back != null))
  							{
  								lines[i].FlipVertices();
  								lines[i].FlipSidedefs();
  							}
  							
  							// Update sided flags
  							lines[i].ApplySidedFlags();
  						}
  					}
  				}
  
  				// Update cache values
  				General.Map.IsChanged = true;
  				General.Map.Map.Update();
  				
  				// Make text labels for sectors
  				SetupLabels();
  				UpdateSelectedLabels();
  				
  				// Redraw screen
  				General.Interface.RedrawDisplay();
  			}
  		}
  		
  		// This joins sectors together and keeps all lines
  		[BeginAction("joinsectors")]
  		public void JoinSectors()
  		{
  			// Worth our money?
  			int count = General.Map.Map.GetSelectedSectors(true).Count;
  			if(count > 1)
  			{
  				// Make undo
  				General.Map.UndoRedo.CreateUndo("Join " + count + " sectors");
  				General.Interface.DisplayStatus(StatusType.Action, "Joined " + count + " sectors.");
  
  				// Merge
  				JoinMergeSectors(false);
  
  				// Deselect
  				General.Map.Map.ClearSelectedSectors();
  				General.Map.Map.ClearSelectedLinedefs();
  				General.Map.IsChanged = true;
  
  				// Redraw display
  				General.Interface.RedrawDisplay();
  			}
  		}
  
  		// This joins sectors together and removes the lines in between
  		[BeginAction("mergesectors")]
  		public void MergeSectors()
  		{
  			// Worth our money?
  			int count = General.Map.Map.GetSelectedSectors(true).Count;
  			if(count > 1)
  			{
  				// Make undo
  				General.Map.UndoRedo.CreateUndo("Merge " + count + " sectors");
  				General.Interface.DisplayStatus(StatusType.Action, "Merged " + count + " sectors.");
  
  				// Merge
  				JoinMergeSectors(true);
  
  				// Deselect
  				General.Map.Map.ClearSelectedSectors();
  				General.Map.Map.ClearSelectedLinedefs();
  				General.Map.IsChanged = true;
  
  				// Redraw display
  				General.Interface.RedrawDisplay();
  			}
  		}
  
  		// Make gradient brightness
  		[BeginAction("gradientbrightness")]
  		public void MakeGradientBrightness()
  		{
  			General.Interface.DisplayStatus(StatusType.Action, "Created gradient brightness over selected sectors.");
  			General.Map.UndoRedo.CreateUndo("Gradient brightness");
  
  			// Need at least 3 selected sectors
  			// The first and last are not modified
  			ICollection<Sector> orderedselection = General.Map.Map.GetSelectedSectors(true);
  			if(orderedselection.Count > 2)
  			{
  				float startbrightness = (float)General.GetByIndex(orderedselection, 0).Brightness;
  				float endbrightness = (float)General.GetByIndex(orderedselection, orderedselection.Count - 1).Brightness;
  
gt: 				float delta = endbrightness - startbrightness;