#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.Generic;
using System.Drawing;
using System.Windows.Forms;
using CodeImp.DoomBuilder.Actions;
using CodeImp.DoomBuilder.Config;
using CodeImp.DoomBuilder.Controls;
using CodeImp.DoomBuilder.Data;
using CodeImp.DoomBuilder.Editing;
using CodeImp.DoomBuilder.Geometry;
using CodeImp.DoomBuilder.Map;
using CodeImp.DoomBuilder.Rendering;
using CodeImp.DoomBuilder.Types;
using CodeImp.DoomBuilder.Windows;

#endregion

namespace CodeImp.DoomBuilder.BuilderModes
{
	[EditMode(DisplayName = "Edit Selection Mode",
			  SwitchAction = "editselectionmode",
			  ButtonImage = "Selection3.png",
			  ButtonOrder = 1,
			  ButtonGroup = "002_modify",
			  Volatile = true,
			  UseByDefault = true,
			  Optional = false)]

	public class EditSelectionMode : BaseClassicMode
	{
		#region ================== Enums

		private enum ModifyMode
		{
			None,
			Dragging,
			Resizing,
			Rotating
		}

		private enum Grip
		{
			None,
			Main,
			SizeN,
			SizeS,
			SizeE,
			SizeW,
			RotateLT,
			RotateRT,
			RotateRB,
			RotateLB
		}

		internal enum HeightAdjustMode
		{
			NONE,
			ADJUST_FLOORS,
			ADJUST_CEILINGS,
			ADJUST_BOTH,
		}

		#endregion

		#region ================== Structs (mxd)

		private struct SectorTextureInfo
		{
			public readonly SurfaceTextureInfo Floor;
			public readonly SurfaceTextureInfo Ceiling;

			public SectorTextureInfo(Sector s)
			{
				// Get transform properties
				Floor.Offset = new Vector2D(UniFields.GetFloat(s.Fields, "xpanningfloor", 0f), UniFields.GetFloat(s.Fields, "ypanningfloor", 0f));
				Ceiling.Offset = new Vector2D(UniFields.GetFloat(s.Fields, "xpanningceiling", 0f), UniFields.GetFloat(s.Fields, "ypanningceiling", 0f));
				Floor.Scale = new Vector2D(UniFields.GetFloat(s.Fields, "xscalefloor", 1.0f), -UniFields.GetFloat(s.Fields, "yscalefloor", 1.0f));
				Ceiling.Scale = new Vector2D(UniFields.GetFloat(s.Fields, "xscaleceiling", 1.0f), -UniFields.GetFloat(s.Fields, "yscaleceiling", 1.0f));
				Floor.Rotation = Angle2D.DegToRad(UniFields.GetFloat(s.Fields, "rotationfloor", 0f));
				Ceiling.Rotation = Angle2D.DegToRad(UniFields.GetFloat(s.Fields, "rotationceiling", 0f));

				// Get texture sizes
				Floor.TextureSize = GetTextureSize(s.LongFloorTexture);
				Ceiling.TextureSize = GetTextureSize(s.LongCeilTexture);

				// Surface name
				Floor.Part = "floor";
				Ceiling.Part = "ceiling";
			}

			private static Size GetTextureSize(long hash)
			{
				ImageData texture = General.Map.Data.GetFlatImage(hash);
				if((texture == null) || (texture == General.Map.Data.WhiteTexture) ||
				   (texture.Width <= 0) || (texture.Height <= 0) || !texture.IsImageLoaded) 
				{
					return new Size();
				}

				return new Size((int)Math.Round(texture.ScaledWidth), (int)Math.Round(texture.ScaledHeight));
			}
		}

		private struct SurfaceTextureInfo
		{
			public Vector2D Offset;
			public Vector2D Scale;
			public Size TextureSize;
			public float Rotation;
			public string Part;
		}

		#endregion

		#region ================== Constants

		private const float GRIP_SIZE = 9.0f;
		private const float ZERO_SIZE_ADDITION = 20.0f;
		private const byte RECTANGLE_ALPHA = 60;
		private const byte EXTENSION_LINE_ALPHA = 150;
		private readonly Cursor[] RESIZE_CURSORS = { Cursors.SizeNS, Cursors.SizeNWSE, Cursors.SizeWE, Cursors.SizeNESW };
		
		#endregion

		#region ================== Variables

		// Modes
		private bool modealreadyswitching;
		private bool clearselection; //mxd
		private bool pasting;
		private bool autodrag; //mxd
		private PasteOptions pasteoptions;
		private HeightAdjustMode heightadjustmode; //mxd
		
		// Docker
		private EditSelectionPanel panel;
		private Docker docker;
		
		// Highlighted vertex
		private MapElement highlighted;
		private Vector2D highlightedpos;

		// Selection
		private ICollection<Vertex> selectedvertices;
		private ICollection<Thing> selectedthings;
		private Dictionary<Sector, SectorTextureInfo> selectedsectors; //mxd
		private List<int> fixedrotationthingtypes; //mxd 
		private ICollection<Linedef> selectedlines;
		private List<Vector2D> vertexpos;
		private List<Vector2D> thingpos;
		private List<float> thingangle;
		private ICollection<Vertex> unselectedvertices;
		private ICollection<Linedef> unselectedlines;
		private ICollection<Linedef> unstablelines; //mxd
		private Dictionary<Sector, float[]> slopeheights;

		// Modification
		private float rotation;
		private Vector2D offset;
		private Vector2D size;
		private Vector2D scale = new Vector2D(1.0f, 1.0f); //mxd
		private Vector2D baseoffset;
		private Vector2D basesize;
		private bool linesflipped;
		private bool usepreciseposition; //mxd

		//mxd. Texture modification
		private static bool transformflooroffsets;
		private static bool transformceiloffsets;
		private static bool rotateflooroffsets;
		private static bool rotateceiloffsets;
		private static bool scaleflooroffsets;
		private static bool scaleceiloffsets;
		private Vector2D selectioncenter;
		private Vector2D selectionbasecenter;
		
		// Modifying Modes
		private ModifyMode mode;
		private Vector2D dragoffset;
		private Vector2D resizefilter;
		private Vector2D resizevector;
		private Vector2D edgevector;
		private Line2D resizeaxis;
		private int stickcorner;
		private float rotategripangle;
		private bool autopanning;
		
		// Rectangle components
		private Vector2D[] originalcorners; // lefttop, righttop, rightbottom, leftbottom
		private Vector2D[] corners;
		private FlatVertex[] cornerverts;
		private RectangleF[] resizegrips;	// top, right, bottom, left
		private RectangleF[] rotategrips;   // lefttop, righttop, rightbottom, leftbottom
		private Line2D extensionline;

		// Options
		private bool snaptogrid;		// SHIFT to toggle
		private bool snaptonearest;		// CTRL to enable
		
		#endregion

		#region ================== Properties

		public override object HighlightedObject { get { return highlighted; } }
		
		public bool Pasting { get { return pasting; } set { pasting = value; } }
		public PasteOptions PasteOptions { get { return pasteoptions; } set { pasteoptions = value.Copy(); } }

		//mxd. Modification
		internal bool UsePrecisePosition { get { return usepreciseposition; } set { usepreciseposition = value; } }

		//mxd. Texture offset properties
		internal bool TransformFloorOffsets { get { return transformflooroffsets; } set { transformflooroffsets = value; UpdateAllChanges(); } }
		internal bool TransformCeilingOffsets { get { return transformceiloffsets; } set { transformceiloffsets = value; UpdateAllChanges(); } }
		internal bool RotateFloorOffsets { get { return rotateflooroffsets; } set { rotateflooroffsets = value; UpdateAllChanges(); } }
		internal bool RotateCeilingOffsets { get { return rotateceiloffsets; } set { rotateceiloffsets = value; UpdateAllChanges(); } }
		internal bool ScaleFloorOffsets { get { return scaleflooroffsets; } set { scaleflooroffsets = value; UpdateAllChanges(); } }
		internal bool ScaleCeilingOffsets { get { return scaleceiloffsets; } set { scaleceiloffsets = value; UpdateAllChanges(); } }

		//mxd. Height offset mode
		internal HeightAdjustMode SectorHeightAdjustMode { get { return heightadjustmode; } set { heightadjustmode = value; } }

		#endregion

		#region ================== Constructor / Disposer

		// Constructor
		public EditSelectionMode()
		{
			// Initialize
			mode = ModifyMode.None;
		}

		//mxd. Another constructor. Used indirectly from ImportObjAsTerrainMode.OnAccept.
		public EditSelectionMode(bool pasting)
		{
			// Initialize
			this.pasting = pasting;
			this.mode = ModifyMode.None;
		}

		// Disposer
		public override void Dispose()
		{
			// Not already disposed?
			if(!isdisposed)
			{
				// Clean up

				// Dispose base
				base.Dispose();
			}
		}

		#endregion
		
		#region ================== Methods
		
		// The following functions set different properties and update
		
		public void SetAbsPosX(float posx)
		{
			offset.x = posx;
			UpdateAllChanges();
		}
		
		public void SetAbsPosY(float posy)
		{
			offset.y = posy;
			UpdateAllChanges();
		}
		
		public void SetRelPosX(float posx)
		{
			offset.x = posx + baseoffset.x;
			UpdateAllChanges();
		}
		
		public void SetRelPosY(float posy)
		{
			offset.y = posy + baseoffset.y;
			UpdateAllChanges();
		}
		
		public void SetAbsSizeX(float sizex)
		{
			size.x = sizex;
			UpdateAllChanges();
		}
		
		public void SetAbsSizeY(float sizey)
		{
			size.y = sizey;
			UpdateAllChanges();
		}
		
		public void SetRelSizeX(float sizex)
		{
			size.x = basesize.x * (sizex / 100.0f);
			UpdateAllChanges();
		}
		
		public void SetRelSizeY(float sizey)
		{
			size.y = basesize.y * (sizey / 100.0f);
			UpdateAllChanges();
		}

		public void SetAbsRotation(float absrot)
		{
			rotation = absrot;
			UpdateAllChanges();
		}
		
		// This updates all after changes were made
		private void UpdateAllChanges()
		{
			UpdateGeometry();
			UpdateRectangleComponents();
			if(General.Map.UDMF) UpdateTextureTransform(); //mxd
			General.Map.Map.Update();
			General.Interface.RedrawDisplay();
		}
		
		// This highlights a new vertex
		private void Highlight(MapElement h)
		{
			// Undraw previous highlight
			if(highlighted != null && !highlighted.IsDisposed)
			{
				if(highlighted is Vertex)
				{
					if(renderer.StartPlotter(false))
					{
						renderer.PlotVertex((Vertex)highlighted, renderer.DetermineVertexColor((Vertex)highlighted));
						renderer.Finish();
					}
				}
				else
				{
					if(renderer.StartThings(false))
					{
						renderer.RenderThing((Thing)highlighted, renderer.DetermineThingColor((Thing)highlighted), General.Settings.ActiveThingsAlpha);
						renderer.Finish();
					}
				}
			}
			
			// Set new highlight
			highlighted = h;

			// Render highlighted item
			if(highlighted != null && !highlighted.IsDisposed)
			{
				if(highlighted is Vertex)
				{
					if(renderer.StartPlotter(false))
					{
						renderer.PlotVertex((Vertex)highlighted, ColorCollection.HIGHLIGHT);
						renderer.Finish();
					}
				}
				else
				{
					if(renderer.StartThings(false))
					{
						renderer.RenderThing((Thing)highlighted, General.Colors.Highlight, General.Settings.ActiveThingsAlpha);
						renderer.Finish();
					}
				}
			}

			// Done
			renderer.Present();
		}
		
		// This updates the selection
		private void Update()
		{
			// biwa. This is a fix for autodrag, since it will actually fire OnMouseLeave and would crash when Update is called while the
			// mouse is outside the window. This does *not* happen when dragging without autodrag.
			if (!mouseinside) return;

			// Not in any modifying mode?
			if(mode == ModifyMode.None)
			{
				// Check what grip the mouse is over
				// and change cursor accordingly
				Grip mousegrip = (autodrag ? Grip.Main : CheckMouseGrip()); //mxd. We only want to move when starting auto-dragging
				switch(mousegrip)
				{
					case Grip.Main:
						
						// Find the nearest vertex within highlight range
						Vertex v = MapSet.NearestVertex(selectedvertices, mousemappos);
						
						// Find the nearest thing within range
						Thing t = MapSet.NearestThing(selectedthings, mousemappos);
						
						// Highlight the one that is closer
						if((v != null) && (t != null))
						{
							if(v.DistanceToSq(mousemappos) < t.DistanceToSq(mousemappos))
							{
								if(v != highlighted) Highlight(v);
							}
							else
							{
								if(t != highlighted) Highlight(t);
							}
						}
						else if(v != null)
						{
							if(v != highlighted) Highlight(v);
						}
						else
						{
							if(t != highlighted) Highlight(t);
						}
						
						General.Interface.SetCursor(Cursors.Hand);
						break;

					case Grip.RotateLB:
					case Grip.RotateLT:
					case Grip.RotateRB:
					case Grip.RotateRT:
						Highlight(null);
						General.Interface.SetCursor(Cursors.Cross);
						break;

					case Grip.SizeE:
					case Grip.SizeS:
					case Grip.SizeW:
					case Grip.SizeN:
						// Pick the best matching cursor depending on rotation and side
						float resizeangle = rotation;
						if((mousegrip == Grip.SizeE) || (mousegrip == Grip.SizeW)) resizeangle += Angle2D.PIHALF;
						resizeangle = Angle2D.Normalized(resizeangle);
						if(resizeangle > Angle2D.PI) resizeangle -= Angle2D.PI;
						resizeangle = Math.Abs(resizeangle + Angle2D.PI / 8.000001f);
						int cursorindex = (int)Math.Floor((resizeangle / Angle2D.PI) * 4.0f) % 4;
						General.Interface.SetCursor(RESIZE_CURSORS[cursorindex]);
						Highlight(null);
						break;

					default:
						Highlight(null);
						General.Interface.SetCursor(Cursors.Default);
						break;
				}
			}
			else
			{
				Vector2D snappedmappos = mousemappos;
				bool dosnaptogrid = snaptogrid;

				// Options
				snaptogrid = General.Interface.ShiftState ^ General.Interface.SnapToGrid;
				snaptonearest = General.Interface.CtrlState ^ General.Interface.AutoMerge;

				// Change to crosshair cursor so we can clearly see around the mouse cursor
				General.Interface.SetCursor(Cursors.Cross);
				
				// Check what modifying mode we are in
				switch(mode)
				{
					// Dragging
					case ModifyMode.Dragging:
						// Change offset without snapping
						offset = mousemappos - dragoffset;
						
						// Calculate transformed position of highlighted vertex
						Vector2D transformedpos = TransformedPoint(highlightedpos);
						
						// Snap to nearest vertex?
						if(snaptonearest && (highlighted != null))
						{
							float vrange = BuilderPlug.Me.StitchRange / renderer.Scale;

							// Try the nearest vertex
							Vertex nv = MapSet.NearestVertexSquareRange(unselectedvertices, transformedpos, vrange);
							if(nv != null)
							{
								// Change offset to snap to target
								offset += nv.Position - transformedpos;
								dosnaptogrid = false;
							}
							else
							{
								// Find the nearest unselected line within range
								Linedef nl = MapSet.NearestLinedefRange(unselectedlines, transformedpos, BuilderPlug.Me.StitchRange / renderer.Scale);
								if(nl != null)
								{
									// Snap to grid?
									if(dosnaptogrid)
									{
										// Get grid intersection coordinates
										List<Vector2D> coords = nl.GetGridIntersections();
										
										// Find nearest grid intersection
										float found_distance = float.MaxValue;
										Vector2D found_pos = new Vector2D(float.NaN, float.NaN);
										foreach(Vector2D v in coords)
										{
											Vector2D dist = transformedpos - v;
											if(dist.GetLengthSq() < found_distance)
											{
												// Found a better match
												found_distance = dist.GetLengthSq();
												found_pos = v;
												
												// Do not snap to grid anymore
												dosnaptogrid = false;
											}
										}

										// Found something?
										if(!float.IsNaN(found_pos.x))
										{
											// Change offset to snap to target
											offset += found_pos - transformedpos;
										}
									}
									else
									{
										// Change offset to snap onto the line
										offset += nl.NearestOnLine(transformedpos) - transformedpos;
									}
								}
							}
						}

						// Snap to grid?
						if(dosnaptogrid && (highlighted != null))
						{
							// Change offset to align to grid
							offset += General.Map.Grid.SnappedToGrid(transformedpos) - transformedpos;
						}

						// Update
						UpdateGeometry();
						UpdateRectangleComponents();
						General.Interface.RedrawDisplay();
						break;

					// Resizing
					case ModifyMode.Resizing:
						// Snap to nearest vertex?
						if(snaptonearest)
						{
							float vrange = BuilderPlug.Me.StitchRange / renderer.Scale;
							
							// Try the nearest vertex
							Vertex nv = MapSet.NearestVertexSquareRange(unselectedvertices, snappedmappos, vrange);
							if(nv != null)
							{
								snappedmappos = nv.Position;
								dosnaptogrid = false;
							}
						}
						
						// Snap to grid?
						if(dosnaptogrid)
						{
							// Aligned to grid
							snappedmappos = General.Map.Grid.SnappedToGrid(snappedmappos);
						}
						
						// Keep corner position
						Vector2D oldcorner = corners[stickcorner];
						
						// Change size with the scale from the ruler
						float newscale = resizeaxis.GetNearestOnLine(snappedmappos);
						size = (basesize * resizefilter) * newscale + size * (1.0f - resizefilter);

						//mxd. Update scale
						newscale = 1f / newscale;
						if(float.IsInfinity(newscale) || float.IsNaN(newscale)) newscale = 99999f;
						scale = (newscale * resizefilter) + scale * (1.0f - resizefilter);
						if(float.IsInfinity(scale.x) || float.IsNaN(scale.x)) scale.x = 99999f;
						if(float.IsInfinity(scale.y) || float.IsNaN(scale.y)) scale.y = 99999f;
						
						// Adjust corner position
						Vector2D newcorner = TransformedPoint(originalcorners[stickcorner]);
						offset -= newcorner - oldcorner;
						
						// Show the extension line so that the user knows what it is aligning to
						Vector2D sizefiltered = (size * resizefilter);
						float sizelength = sizefiltered.x + sizefiltered.y;
						Line2D edgeline = new Line2D(resizeaxis.v1 + resizevector * sizelength, resizeaxis.v1 + resizevector * sizelength - edgevector);
						float nearestonedge = edgeline.GetNearestOnLine(snappedmappos);
						if(nearestonedge > 0.5f)
							extensionline = new Line2D(edgeline.v1, snappedmappos);
						else
							extensionline = new Line2D(edgeline.v2, snappedmappos);
						
						// Update
						UpdateGeometry();
						UpdateRectangleComponents();
						General.Interface.RedrawDisplay();
						break;

					// Rotating
					case ModifyMode.Rotating:
						// Get angle from mouse to center
						Vector2D center = offset + size * 0.5f;
						Vector2D delta = snappedmappos - center;
						rotation = delta.GetAngle() - rotategripangle;
						
						// Snap rotation to grip?
						if(dosnaptogrid)
						{
							// We make 24 vectors that the rotation can snap to
							float founddistance = float.MaxValue;
							float foundrotation = rotation;
							Vector3D rotvec = Vector2D.FromAngle(rotation);
							
							for(int i = 0; i < 24; i++)
							{
								// Make the vectors
								float angle = i * Angle2D.PI * 0.08333333333f; //mxd. 15-degree increments
								Vector2D gridvec = Vector2D.FromAngle(angle);
								
								// Check distance
								float dist = 2.0f - Vector2D.DotProduct(gridvec, rotvec);
								if(dist < founddistance)
								{
									foundrotation = angle;
									founddistance = dist;
								}
							}
							
							// Keep rotation
							rotation = foundrotation;
						}
						
						// Update
						UpdateGeometry();
						UpdateRectangleComponents();
						General.Interface.RedrawDisplay();
						break;
				}
			}
		}
		
		// This checks and returns the grip the mouse pointer is in
		private Grip CheckMouseGrip()
		{
			if(PointInRectF(resizegrips[0], mousemappos)) return Grip.SizeN;
			if(PointInRectF(resizegrips[2], mousemappos)) return Grip.SizeS;
			if(PointInRectF(resizegrips[1], mousemappos)) return Grip.SizeE;
			if(PointInRectF(resizegrips[3], mousemappos)) return Grip.SizeW;
			if(PointInRectF(rotategrips[0], mousemappos)) return Grip.RotateLT;
			if(PointInRectF(rotategrips[1], mousemappos)) return Grip.RotateRT;
			if(PointInRectF(rotategrips[2], mousemappos)) return Grip.RotateRB;
			if(PointInRectF(rotategrips[3], mousemappos)) return Grip.RotateLB;
			if(Tools.PointInPolygon(corners, mousemappos)) return Grip.Main;
			return Grip.None;
		}
		
		// This applies the current rotation and resize to a point
		private Vector2D TransformedPoint(Vector2D p)
		{
			// Resize
			p = (p - baseoffset) * (size / basesize) + baseoffset;
			
			// Rotate
			Vector2D center = baseoffset + size * 0.5f;
			Vector2D po = p - center;
			p = po.GetRotated(rotation);
			p += center;
			
			// Translate
			p += offset - baseoffset;
			
			return p;
		}

		// This applies the current rotation and resize to a point
		private Vector2D TransformedPointNoScale(Vector2D p)
		{
			// Rotate
			Vector2D center = baseoffset + size * 0.5f;
			Vector2D po = p - center;
			p = po.GetRotated(rotation);
			p += center;

			// Translate
			p += offset - baseoffset;

			return p;
		}
		
		// This applies the current rotation and resize to a point
		private Vector2D TransformedPointNoRotate(Vector2D p)
		{
			// Resize
			p = (p - baseoffset) * (size / basesize) + baseoffset;
			
			// Translate
			p += offset - baseoffset;
			
			return p;
		}

		// This applies the current rotation and resize to a point
		private Vector2D TransformedPointNoRotateNoScale(Vector2D p)
		{
			// Translate
			p += offset - baseoffset;

			return p;
		}
		
		// This checks if a point is in a rect
		private static bool PointInRectF(RectangleF rect, Vector2D point)
		{
			return !(point.x < rect.Left || point.x > rect.Right || point.y < rect.Top || point.y > rect.Bottom); //mxd
		}
		
		// This updates the values in the panel
		private void UpdatePanel()
		{
			Vector2D relsize = (size / basesize) * 100.0f;
			if(panel != null)
				panel.ShowCurrentValues(offset, offset - baseoffset, size, relsize, rotation);
		}

		// This moves all things and vertices to match the current transformation
		private void UpdateGeometry()
		{
			float[] newthingangle = thingangle.ToArray();
			int index;

			// Flip things horizontally
			if(size.x < 0.0f)
			{
				for(index = 0; index < newthingangle.Length; index++)
				{
					// Check quadrant
					if((newthingangle[index] >= 0f) && (newthingangle[index] < Angle2D.PIHALF))
						newthingangle[index] = newthingangle[index] - (newthingangle[index] * 2);
					else if((newthingangle[index] >= Angle2D.PIHALF) && (newthingangle[index] <= Angle2D.PI))
						newthingangle[index] = newthingangle[index] + (Angle2D.PI - newthingangle[index]) * 2;
					else if((newthingangle[index] >= Angle2D.PI) && (newthingangle[index] <= Angle2D.PI + Angle2D.PIHALF))
						newthingangle[index] = newthingangle[index] - (newthingangle[index] - Angle2D.PI) * 2;
					else
						newthingangle[index] = newthingangle[index] + (Angle2D.PI2 - newthingangle[index]) * 2;
				}
			}

			// Flip things vertically
			if(size.y < 0.0f)
			{
				for(index = 0; index < newthingangle.Length; index++)
				{
					// Check quadrant
					if((newthingangle[index] >= 0f) && (newthingangle[index] < Angle2D.PIHALF))
						newthingangle[index] = newthingangle[index] + (Angle2D.PI - newthingangle[index] * 2);
					else if((newthingangle[index] >= Angle2D.PIHALF) && (newthingangle[index] <= Angle2D.PI))
						newthingangle[index] = newthingangle[index] - (newthingangle[index] - Angle2D.PIHALF) * 2;
					else if((newthingangle[index] >= Angle2D.PI) && (newthingangle[index] <= Angle2D.PI + Angle2D.PIHALF))
						newthingangle[index] = newthingangle[index] + (Angle2D.PI - (newthingangle[index] - Angle2D.PI) * 2);
					else
						newthingangle[index] = newthingangle[index] - (newthingangle[index] - (Angle2D.PI + Angle2D.PIHALF)) * 2;
				}
			}

			// We use optimized versions of the TransformedPoint depending on what needs to be done.
			// This is mainly done because 0.0 rotation and 1.0 scale may still give slight inaccuracies.
			bool norotate = Math.Abs(rotation) < 0.0001f;
			bool noscale = Math.Abs(size.x - basesize.x) + Math.Abs(size.y - basesize.y) < 0.0001f;
			if(norotate && noscale)
			{
				index = 0;
				foreach(Vertex v in selectedvertices)
				{
					v.Move(TransformedPointNoRotateNoScale(vertexpos[index++]));
				}
				index = 0;
				foreach(Thing t in selectedthings)
				{
					t.Move(TransformedPointNoRotateNoScale(thingpos[index++]));
				}
			}
			else if(norotate)
			{
				index = 0;
				foreach(Vertex v in selectedvertices)
				{
					v.Move(TransformedPointNoRotate(vertexpos[index++]));
				}
				index = 0;
				foreach(Thing t in selectedthings)
				{
					t.Move(TransformedPointNoRotate(thingpos[index++]));
				}
			}
			else if(noscale)
			{
				index = 0;
				foreach(Vertex v in selectedvertices)
				{
					v.Move(TransformedPointNoScale(vertexpos[index++]));
				}
				index = 0;
				foreach(Thing t in selectedthings)
				{
					newthingangle[index] = Angle2D.Normalized(newthingangle[index] + rotation);
					t.Move(TransformedPointNoScale(thingpos[index++]));
				}
			}
			else
			{
				index = 0;
				foreach(Vertex v in selectedvertices)
				{
					v.Move(TransformedPoint(vertexpos[index++]));
				}
				index = 0;
				foreach(Thing t in selectedthings)
				{
					newthingangle[index] = Angle2D.Normalized(newthingangle[index] + rotation);
					t.Move(TransformedPoint(thingpos[index++]));
				}
			}

			// This checks if the lines should be flipped
			bool shouldbeflipped = (size.x < 0.0f) ^ (size.y < 0.0f);
			if(shouldbeflipped != linesflipped) FlipLinedefs();

			// Apply new thing rotations
			index = 0;
			foreach(Thing t in selectedthings)
			{
				//mxd. Added special Polyobj Anchor handling and Doom angle clamping
				if(!fixedrotationthingtypes.Contains(t.Type))
				{
					int newangle = Angle2D.RealToDoom(Angle2D.Normalized(newthingangle[index]));
					if(General.Map.Config.DoomThingRotationAngles) newangle = newangle / 45 * 45;
					t.Rotate(newangle);
				}
				
				index++;
			}
			
			UpdatePanel();
			General.Map.Map.Update(true, false);
		}

		//mxd. This updates texture transforms for all sectors
		private void UpdateTextureTransform() 
		{
			foreach(KeyValuePair<Sector, SectorTextureInfo> group in selectedsectors) 
			{
				group.Key.Fields.BeforeFieldsChange();

				// Apply transforms
				UpdateTextureTransform(group.Key.Fields, group.Value.Ceiling, transformceiloffsets, rotateceiloffsets, scaleceiloffsets);
				UpdateTextureTransform(group.Key.Fields, group.Value.Floor, transformflooroffsets, rotateflooroffsets, scaleflooroffsets);

				// Update cache
				group.Key.UpdateNeeded = true;
				group.Key.UpdateCache();
			}

			// Map was changed
			General.Map.IsChanged = true;
		}

		//mxd. This updates texture transforms in given UniFields
		private void UpdateTextureTransform(UniFields fields, SurfaceTextureInfo si, bool transformoffsets, bool rotateoffsets, bool scaleoffsets)
		{
			// Get offset-ready values
			float texrotation = Angle2D.PI2 - rotation;

			// Update texture offsets
			if (transformoffsets)
			{
				float trotation = rotateoffsets ? (si.Rotation + texrotation) : (si.Rotation);
				Vector2D offset = selectioncenter.GetRotated(trotation);

				fields["xpanning" + si.Part] = new UniValue(UniversalType.Float, (float)Math.Round(-offset.x, General.Map.FormatInterface.VertexDecimals));
				fields["ypanning" + si.Part] = new UniValue(UniversalType.Float, (float)Math.Round(offset.y, General.Map.FormatInterface.VertexDecimals));

			}
			// Restore texture offsets
			else 
			{
				fields["xpanning" + si.Part] = new UniValue(UniversalType.Float, si.Offset.x);
				fields["ypanning" + si.Part] = new UniValue(UniversalType.Float, si.Offset.y);
			}

			// Update rotation
			if(rotateoffsets)
				fields["rotation" + si.Part] = new UniValue(UniversalType.AngleDegreesFloat, General.ClampAngle((float)Math.Round(Angle2D.RadToDeg(si.Rotation + texrotation), General.Map.FormatInterface.VertexDecimals)));
			// Restore rotation
			else 
				fields["rotation" + si.Part] = new UniValue(UniversalType.AngleDegreesFloat, Angle2D.RadToDeg(si.Rotation));

			// Update scale
			if(scaleoffsets)
			{
				fields["xscale" + si.Part] = new UniValue(UniversalType.Float, (float) Math.Round(si.Scale.x * scale.x, General.Map.FormatInterface.VertexDecimals));
				fields["yscale" + si.Part] = new UniValue(UniversalType.Float, (float) Math.Round(-si.Scale.y * scale.y, General.Map.FormatInterface.VertexDecimals));
			}
			// Restore scale
			else 
			{
				fields["xscale" + si.Part] = new UniValue(UniversalType.Float, si.Scale.x);
				fields["yscale" + si.Part] = new UniValue(UniversalType.Float, -si.Scale.y);
			}
		}

		//mxd. This restores texture transforms for all sectors
		private void RestoreTextureTransform() 
		{
			foreach(KeyValuePair<Sector, SectorTextureInfo> group in selectedsectors)
			{
				group.Key.Fields.BeforeFieldsChange();

				// Revert transforms
				RestoreTextureTransform(group.Key.Fields, group.Value.Ceiling);
				RestoreTextureTransform(group.Key.Fields, group.Value.Floor);

				// Update cache
				group.Key.UpdateNeeded = true;
				group.Key.UpdateCache();
			}
		}

		//mxd. This restores texture transforms in given UniFields
		private static void RestoreTextureTransform(UniFields fields, SurfaceTextureInfo si)
		{
			fields["rotation" + si.Part] = new UniValue(UniversalType.AngleDegreesFloat, Angle2D.RadToDeg(si.Rotation));
			fields["xscale" + si.Part]   = new UniValue(UniversalType.Float, si.Scale.x);
			fields["yscale" + si.Part]   = new UniValue(UniversalType.Float, -si.Scale.y);
			fields["xpanning" + si.Part] = new UniValue(UniversalType.Float, si.Offset.x);
			fields["ypanning" + si.Part] = new UniValue(UniversalType.Float, si.Offset.y);
		}
		
		// This updates the selection rectangle components
		private void UpdateRectangleComponents()
		{
			float gripsize = GRIP_SIZE / renderer.Scale;
			PixelColor rectcolor = General.Colors.Highlight.WithAlpha(RECTANGLE_ALPHA);

			// Original (untransformed) corners
			originalcorners = new Vector2D[4];
			originalcorners[0] = new Vector2D(baseoffset.x, baseoffset.y);
			originalcorners[1] = new Vector2D(baseoffset.x + basesize.x, baseoffset.y);
			originalcorners[2] = new Vector2D(baseoffset.x + basesize.x, baseoffset.y + basesize.y);
			originalcorners[3] = new Vector2D(baseoffset.x, baseoffset.y + basesize.y);

			// Corners
			corners = new Vector2D[4];
			for(int i = 0; i < 4; i++)
				corners[i] = TransformedPoint(originalcorners[i]);

			// Vertices
			cornerverts = new FlatVertex[6];
			for(int i = 0; i < 6; i++)
			{
				cornerverts[i] = new FlatVertex();
				cornerverts[i].z = 1.0f;
				cornerverts[i].c = rectcolor.ToInt();
			}
			cornerverts[0].x = corners[0].x;
			cornerverts[0].y = corners[0].y;
			cornerverts[1].x = corners[1].x;
			cornerverts[1].y = corners[1].y;
			cornerverts[2].x = corners[2].x;
			cornerverts[2].y = corners[2].y;
			cornerverts[3].x = corners[0].x;
			cornerverts[3].y = corners[0].y;
			cornerverts[4].x = corners[2].x;
			cornerverts[4].y = corners[2].y;
			cornerverts[5].x = corners[3].x;
			cornerverts[5].y = corners[3].y;
			
			// Middle points between corners
			Vector2D middle01 = corners[0] + (corners[1] - corners[0]) * 0.5f;
			Vector2D middle12 = corners[1] + (corners[2] - corners[1]) * 0.5f;
			Vector2D middle23 = corners[2] + (corners[3] - corners[2]) * 0.5f;
			Vector2D middle30 = corners[3] + (corners[0] - corners[3]) * 0.5f;
			
			// Resize grips
			resizegrips = new RectangleF[4];
			resizegrips[0] = new RectangleF(middle01.x - gripsize * 0.5f,
											middle01.y - gripsize * 0.5f,
											gripsize, gripsize);
			resizegrips[1] = new RectangleF(middle12.x - gripsize * 0.5f,
											middle12.y - gripsize * 0.5f,
											gripsize, gripsize);
			resizegrips[2] = new RectangleF(middle23.x - gripsize * 0.5f,
											middle23.y - gripsize * 0.5f,
											gripsize, gripsize);
			resizegrips[3] = new RectangleF(middle30.x - gripsize * 0.5f,
											middle30.y - gripsize * 0.5f,
											gripsize, gripsize);

			// Rotate grips
			rotategrips = new RectangleF[4];
			rotategrips[0] = new RectangleF(corners[0].x - gripsize * 0.5f,
											corners[0].y - gripsize * 0.5f,
											gripsize, gripsize);
			rotategrips[1] = new RectangleF(corners[1].x - gripsize * 0.5f,
											corners[1].y - gripsize * 0.5f,
											gripsize, gripsize);
			rotategrips[2] = new RectangleF(corners[2].x - gripsize * 0.5f,
											corners[2].y - gripsize * 0.5f,
											gripsize, gripsize);
			rotategrips[3] = new RectangleF(corners[3].x - gripsize * 0.5f,
											corners[3].y - gripsize * 0.5f,
											gripsize, gripsize);

			//mxd. Update selection center
			selectioncenter = new Vector2D(offset.x + size.x * 0.5f, offset.y + size.y * 0.5f);
		}
		
		// This flips all linedefs in the selection (used for mirroring)
		private void FlipLinedefs()
		{
			//mxd. Check if we need to flip sidedefs
			bool flipsides = false;
			HashSet<Linedef> selectedlineshash = new HashSet<Linedef>(selectedlines);
			foreach(Vertex v in selectedvertices)
			{
				foreach(Linedef l in v.Linedefs)
				{
					if(!selectedlineshash.Contains(l))
					{
						flipsides = true;
						break;
					}
				}
			}

			// Flip linedefs
			foreach(Linedef ld in selectedlines)
			{
				ld.FlipVertices();
				if(flipsides) ld.FlipSidedefs(); //mxd
			}
			
			// Done
			linesflipped = !linesflipped;
		}
	
		#endregion

		#region ================== Sector height adjust methods (mxd)

		//x = floor height, y = ceiling height
		private static Point GetOutsideHeights(HashSet<Sector> sectors)
		{
			Sector target = null;
			Point result = new Point { X = int.MinValue, Y = int.MinValue };
			foreach(Sector s in sectors)
			{
				foreach(Sidedef side in s.Sidedefs)
				{
					// Don't compare with our own stuff, among other things
					if(side.Other == null || side.Other.Sector == null || sectors.Contains(side.Other.Sector)) continue;
					if(target == null)
					{
						target = side.Other.Sector;
						result.X = target.FloorHeight;
						result.Y = target.CeilHeight;
					}
					else if(target != side.Other.Sector)
					{
						// Compare heights
						if(target.FloorHeight != side.Other.Sector.FloorHeight)
							result.X = int.MinValue;
						if(target.CeilHeight != side.Other.Sector.CeilHeight)
							result.Y = int.MinValue;
						
						// We can stop now...
						if(result.X == int.MinValue && result.Y == int.MinValue)
							return result;
					}
				}
			}

			return result;
		}

		private static void AdjustSectorsHeight(HashSet<Sector> toadjust, HeightAdjustMode adjustmode, int oldfloorheight, int oldceilheight)
		{
			// Adjust only when selection is inside a single sector
			if(adjustmode == HeightAdjustMode.NONE || oldfloorheight == int.MinValue || oldceilheight == int.MinValue) return;
			Point outsideheights = GetOutsideHeights(toadjust);
			if(outsideheights.X == int.MinValue && outsideheights.Y == int.MinValue) return;

			// Height differences
			int floorheightdiff = (outsideheights.X == int.MinValue ? int.MinValue : outsideheights.X - oldfloorheight);
			int ceilheightdiff = (outsideheights.Y == int.MinValue ? int.MinValue : outsideheights.Y - oldceilheight);

			switch(adjustmode)
			{
				case HeightAdjustMode.ADJUST_FLOORS:
					if(floorheightdiff != int.MinValue)
					{
						foreach(Sector s in toadjust) AdjustSectorHeight(s, floorheightdiff, int.MinValue);
					}
					break;

				case HeightAdjustMode.ADJUST_CEILINGS:
					if(ceilheightdiff != int.MinValue)
					{
						foreach(Sector s in toadjust) AdjustSectorHeight(s, int.MinValue, ceilheightdiff);
					}
					break;

				case HeightAdjustMode.ADJUST_BOTH:
					foreach(Sector s in toadjust) AdjustSectorHeight(s, floorheightdiff, ceilheightdiff);
					break;

				default:
					throw new NotImplementedException("Unknown HeightAdjustMode: " + adjustmode);
			}
		}

		private static void AdjustSectorHeight(Sector s, int flooroffset, int ceiloffset)
		{
			// Adjust floor height
			if(flooroffset != int.MinValue)
			{
				// Adjust regular height
				s.FloorHeight += flooroffset;

				if(General.Map.UDMF)
				{
					// Adjust slope height?
					if(s.FloorSlope.GetLengthSq() > 0 && !float.IsNaN(s.FloorSlopeOffset / s.FloorSlope.z))
					{
						s.FloorSlopeOffset -= flooroffset * (float)Math.Sin(s.FloorSlope.GetAngleZ());
					}
					// Adjust vertex height?
					else if(s.Sidedefs.Count == 3)
					{
						// Collect verts
						HashSet<Vertex> verts = new HashSet<Vertex>();
						foreach(Sidedef side in s.Sidedefs)
						{
							verts.Add(side.Line.Start);
							verts.Add(side.Line.End);
						}

						// Offset verts
						foreach(Vertex v in verts)
						{
							if(!float.IsNaN(v.ZFloor)) v.ZFloor += flooroffset;
						}
					}
				}
			}

			// Adjust ceiling height
			if(ceiloffset != int.MinValue)
			{
				// Adjust regular height
				s.CeilHeight += ceiloffset;

				if(General.Map.UDMF)
				{
					// Adjust slope height?
					if(s.CeilSlope.GetLengthSq() > 0 && !float.IsNaN(s.CeilSlopeOffset / s.CeilSlope.z))
					{
						s.CeilSlopeOffset -= ceiloffset * (float)Math.Sin(s.CeilSlope.GetAngleZ());
					}
					// Adjust vertex height?
					else if(s.Sidedefs.Count == 3)
					{
						// Collect verts
						HashSet<Vertex> verts = new HashSet<Vertex>();
						foreach(Sidedef side in s.Sidedefs)
						{
							verts.Add(side.Line.Start);
							verts.Add(side.Line.End);
						}

						// Offset verts
						foreach(Vertex v in verts)
						{
							if(!float.IsNaN(v.ZCeiling)) v.ZCeiling += ceiloffset;
						}
					}
				}
			}
		}

		#endregion

		#region ================== Events

		public override void OnHelp()
		{
			General.ShowHelp("e_editselection.html");
		}

		// Mode engages
		public override void OnEngage()
		{
			base.OnEngage();
			
			autodrag = (pasting && mouseinside && BuilderPlug.Me.AutoDragOnPaste);
			snaptonearest = General.Interface.AutoMerge; //mxd
			selectedsectors = new Dictionary<Sector, SectorTextureInfo>(); //mxd

			// Add toolbar buttons
			General.Interface.BeginToolbarUpdate(); //mxd
			General.Interface.AddButton(BuilderPlug.Me.MenusForm.FlipSelectionH);
			General.Interface.AddButton(BuilderPlug.Me.MenusForm.FlipSelectionV);
			General.Interface.EndToolbarUpdate(); //mxd

			//mxd. Get EditPanel-related settings
			usepreciseposition = General.Settings.ReadPluginSetting("editselectionmode.usepreciseposition", true);
			heightadjustmode = (HeightAdjustMode)General.Settings.ReadPluginSetting("editselectionmode.heightadjustmode", (int)HeightAdjustMode.NONE);
			
			// Add docker
			panel = new EditSelectionPanel(this);
			docker = new Docker("editselection", "Edit Selection", panel);
			General.Interface.AddDocker(docker, true);
			General.Interface.SelectDocker(docker);
			
			// We don't want to record this for undoing while we move the geometry around.
			// This will be set back to normal when we're done.
			General.Map.UndoRedo.IgnorePropChanges = true;
			
			// Convert geometry selection
			General.Map.Map.ClearAllMarks(false);
			General.Map.Map.MarkSelectedVertices(true, true);
			General.Map.Map.MarkSelectedThings(true, true);
			General.Map.Map.MarkSelectedLinedefs(true, true);
			General.Map.Map.MarkSelectedSectors(true, true);
			ICollection<Vertex> verts = General.Map.Map.GetVerticesFromLinesMarks(true);
			foreach(Vertex v in verts) v.Marked = true;
			ICollection<Sector> sectors = General.Map.Map.GetSelectedSectors(true); //mxd

			foreach(Sector s in sectors)
			{
				foreach(Sidedef sd in s.Sidedefs)
				{
					sd.Line.Marked = true;
					sd.Line.Start.Marked = true;
					sd.Line.End.Marked = true;
				}

				if(General.Map.UDMF) selectedsectors.Add(s, new SectorTextureInfo(s));
			}
			selectedvertices = General.Map.Map.GetMarkedVertices(true);
			selectedthings = General.Map.Map.GetMarkedThings(true);
			unselectedvertices = General.Map.Map.GetMarkedVertices(false);
			
			// Make sure everything is selected so that it turns up red
			foreach(Vertex v in selectedvertices) v.Selected = true;
			ICollection<Linedef> markedlines = General.Map.Map.LinedefsFromMarkedVertices(false, true, false);
			foreach(Linedef l in markedlines) l.Selected = true;
			selectedlines = General.Map.Map.LinedefsFromMarkedVertices(false, true, false);
			unselectedlines = General.Map.Map.LinedefsFromMarkedVertices(true, false, false);
			unstablelines = (pasting ? new List<Linedef>() : General.Map.Map.LinedefsFromMarkedVertices(false, false, true)); //mxd
			
			// Array to keep original coordinates
			vertexpos = new List<Vector2D>(selectedvertices.Count);
			thingpos = new List<Vector2D>(selectedthings.Count);
			thingangle = new List<float>(selectedthings.Count);
			fixedrotationthingtypes = new List<int>(); //mxd

			// A selection must be made!
			if((selectedvertices.Count > 0) || (selectedthings.Count > 0))
			{
				// Initialize offset and size
				offset.x = float.MaxValue;
				offset.y = float.MaxValue;
				Vector2D right;
				right.x = float.MinValue;
				right.y = float.MinValue;
				
				foreach(Vertex v in selectedvertices)
				{
					// Find left-top and right-bottom
					if(v.Position.x < offset.x) offset.x = v.Position.x;
					if(v.Position.y < offset.y) offset.y = v.Position.y;
					if(v.Position.x > right.x) right.x = v.Position.x;
					if(v.Position.y > right.y) right.y = v.Position.y;
					
					// Keep original coordinates
					vertexpos.Add(v.Position);
				}

				foreach(Thing t in selectedthings)
				{
					// Find left-top and right-bottom
					if((t.Position.x - t.Size) < offset.x) offset.x = t.Position.x - t.Size;
					if((t.Position.y - t.Size) < offset.y) offset.y = t.Position.y - t.Size;
					if((t.Position.x + t.Size) > right.x) right.x = t.Position.x + t.Size;
					if((t.Position.y + t.Size) > right.y) right.y = t.Position.y + t.Size;

					if(!fixedrotationthingtypes.Contains(t.Type)) //mxd
					{
						ThingTypeInfo tti = General.Map.Data.GetThingInfoEx(t.Type);
						if(tti != null && tti.FixedRotation) fixedrotationthingtypes.Add(t.Type);
					}

					// Keep original coordinates
					thingpos.Add(t.Position);
					thingangle.Add(t.Angle);
				}

				// Get z heights of floor and ceiling slopes (from the center of the sector). This is used
				// to easily compute the new slope after moving and rotating. We can't simply use the sector
				// heights, since they might be wrong (as sector heights are technically irrelevant for slopes)
				// Floor/ceiling heights are stored if there is no slope, but they won't get used anyway
				// Important: this has to be done before the first call to UpdateGeometry, since that will change
				// the sector and subsequently the bounding box, but not the slope
				slopeheights = new Dictionary<Sector, float[]>();

				foreach(Sector s in sectors)
				{
					// Make sure the sector has a valid bounding box
					s.UpdateBBox();

					Vector2D center = new Vector2D(s.BBox.X + s.BBox.Width / 2, s.BBox.Y + s.BBox.Height / 2);
					float floorz = s.FloorHeight;
					float ceilingz = s.CeilHeight;

					if (!float.IsNaN(s.FloorSlopeOffset) && s.FloorSlope.IsNormalized())
						floorz = new Plane(s.FloorSlope, s.FloorSlopeOffset).GetZ(center);

					if (!float.IsNaN(s.CeilSlopeOffset) && s.CeilSlope.IsNormalized())
						ceilingz = new Plane(s.CeilSlope, s.CeilSlopeOffset).GetZ(center);

					slopeheights.Add(s, new float[] { floorz, ceilingz });
				}
				
				// Calculate size
				size = right - offset;
				
				// If the width of a dimension is zero, add a little
				if(Math.Abs(size.x) < 1.0f)
				{
					size.x += ZERO_SIZE_ADDITION;
					offset.x -= ZERO_SIZE_ADDITION / 2;
				}
				
				if(Math.Abs(size.y) < 1.0f)
				{
					size.y += ZERO_SIZE_ADDITION;
					offset.y -= ZERO_SIZE_ADDITION / 2;
				}
				
				basesize = size;
				baseoffset = offset;
				selectionbasecenter = new Vector2D(offset.x + size.x * 0.5f, offset.y + size.y * 0.5f); //mxd 
				
				// When pasting, we want to move the geometry so it is visible
				if(pasting)
				{
					// Mouse in screen?
					if(mouseinside)
					{
						offset = mousemappos - size / 2;
					}
					else
					{
						Vector2D viewmappos = new Vector2D(renderer.OffsetX, renderer.OffsetY);
						offset = viewmappos - size / 2;
					}

					if(General.Interface.SnapToGrid) //mxd
						offset = General.Map.Grid.SnappedToGrid(offset); 

					UpdateGeometry();
					General.Map.Data.UpdateUsedTextures();

					if(!autodrag) General.Map.Map.Update();
				}
				
				// Set presentation
				if(selectedthings.Count > 0)
					renderer.SetPresentation(Presentation.Things);
				else
					renderer.SetPresentation(Presentation.Standard);
				
				// Update
				panel.ShowOriginalValues(baseoffset, basesize);
				panel.SetTextureTransformSettings(General.Map.UDMF); //mxd
				panel.SetHeightAdjustMode(heightadjustmode, sectors.Count > 0); //mxd
				UpdateRectangleComponents();
				UpdatePanel();
				Update();
				
				// When pasting and mouse is in screen, drag selection immediately
				if(autodrag)
				{
					OnSelectBegin();
					autodrag = false; //mxd. Don't need this any more
				}
			}
			else
			{
				General.Interface.MessageBeep(MessageBeepType.Default);
				General.Interface.DisplayStatus(StatusType.Info, "A selection is required for this action.");
				
				// Cancel now
				General.Editing.CancelMode();
			}
		}

		// Cancel mode
		public override void OnCancel()
		{
			base.OnCancel();

			// Paste operation?
			if(pasting)
			{
				// Resume normal undo/redo recording
				General.Map.UndoRedo.IgnorePropChanges = false;
				
				General.Map.Map.BeginAddRemove(); //mxd

				// Remove the geometry
				foreach(Vertex v in selectedvertices) v.Dispose();
				foreach(Thing t in selectedthings) t.Dispose();

				General.Map.Map.EndAddRemove(); //mxd
				
				// Withdraw the undo
				if(General.Map.UndoRedo.NextUndo != null)
					General.Map.UndoRedo.WithdrawUndo();
			}
			else
			{
				// Reset geometry in original position
				int index = 0;
				foreach(Vertex v in selectedvertices)
					v.Move(vertexpos[index++]);

				index = 0;
				foreach(Thing t in selectedthings)
				{
					t.Rotate(thingangle[index]);
					t.Move(thingpos[index++]);
				}

				//mxd. Reset texture offsets to original values
				if(General.Map.UDMF) RestoreTextureTransform();
				
				// Resume normal undo/redo recording
				General.Map.UndoRedo.IgnorePropChanges = false;
			}
			
			General.Map.Map.Update(true, true);
			
			// Return to previous stable mode
			General.Editing.ChangeMode(General.Editing.PreviousStableMode.Name);
		}

		// When accepted
		public override void OnAccept()
		{
			base.OnAccept();

			// Anything to do?
			if((selectedthings.Count > 0) || (selectedvertices.Count > 0))
			{
				Vector2D tl = new Vector2D(General.Map.Config.RightBoundary, General.Map.Config.BottomBoundary);
				Vector2D br = new Vector2D(General.Map.Config.LeftBoundary, General.Map.Config.RightBoundary);

				foreach(Vertex v in selectedvertices)
				{
					if(v.Position.x < tl.x) tl.x = (int)v.Position.x;
					if(v.Position.x > br.x) br.x = (int)v.Position.x;
					if(v.Position.y > tl.y) tl.y = (int)v.Position.y;
					if(v.Position.y < br.y) br.y = (int)v.Position.y;
				}

				foreach(Thing t in selectedthings)
				{
					if(t.Position.x < tl.x) tl.x = (int)t.Position.x;
					if(t.Position.x > br.x) br.x = (int)t.Position.x;
					if(t.Position.y > tl.y) tl.y = (int)t.Position.y;
					if(t.Position.y < br.y) br.y = (int)t.Position.y;
				}

				// Check if the selection is outside the map boundaries
				if(tl.x < General.Map.Config.LeftBoundary || br.x > General.Map.Config.RightBoundary ||
					tl.y > General.Map.Config.TopBoundary || br.y < General.Map.Config.BottomBoundary)
				{
					General.Interface.DisplayStatus(StatusType.Warning, "Error: selection out of map boundaries.");

					// If we're in the process of switching to another mode, reset to selection
					// to its old position
					if(modealreadyswitching)
					{
						// Reset geometry in original position
						int index = 0;
						foreach(Vertex v in selectedvertices)
							v.Move(vertexpos[index++]);

						index = 0;
						foreach(Thing t in selectedthings)
						{
							t.Rotate(thingangle[index]);
							t.Move(thingpos[index++]);
						}

						//mxd. Reset texture offsets to their original position
						if(General.Map.UDMF) RestoreTextureTransform();

						// Resume normal undo/redo recording
						General.Map.UndoRedo.IgnorePropChanges = false;
						General.Map.Map.Update(true, true);
					}

					return;
				}

				Cursor.Current = Cursors.AppStarting;

				if(!pasting)
				{
					// Reset geometry in original position to create an undo
					if(linesflipped) FlipLinedefs();		// Flip linedefs back if they were flipped
					int index = 0;
					foreach(Vertex v in selectedvertices)
						v.Move(vertexpos[index++]);

					index = 0;
					foreach(Thing t in selectedthings)
					{
						t.Rotate(thingangle[index]);
						t.Move(thingpos[index++]);
					}

					//mxd. Reset texture offsets to their original position
					if(General.Map.UDMF) RestoreTextureTransform();

					General.Map.Map.Update(true, true);
					
					// Make undo
					General.Map.UndoRedo.CreateUndo("Edit selection");
				}

				// Resume normal undo/redo recording
				General.Map.UndoRedo.IgnorePropChanges = false;

				// Mark selected geometry
				General.Map.Map.ClearAllMarks(false);
				General.Map.Map.MarkAllSelectedGeometry(true, true, true, true, false);
				
				// Move geometry to new position
				UpdateGeometry();

				//mxd. Update sector slopes?
				// Do this after UpdateGeometry() because it makes calculating the new slopes much easier
				if (General.Map.UDMF)
				{
					foreach (Sector s in selectedsectors.Keys)
					{
						// Manually update the sector bounding boxes, because they still contain the old values
						s.UpdateBBox();

						// Update floor slope?
						if (s.FloorSlope.GetLengthSq() > 0 && !float.IsNaN(s.FloorSlopeOffset / s.FloorSlope.z))
						{
							float angle = s.FloorSlope.GetAngleXY() + rotation + Angle2D.PIHALF;
							// Not sure what the logic should be for flipping horizintally and/or vertically
							//if (size.x < 0.0f) angle += Angle2D.PI;
							//if (size.y < 0.0f) angle += Angle2D.PI;

							Vector3D center = new Vector3D(s.BBox.X + s.BBox.Width / 2, s.BBox.Y + s.BBox.Height / 2, slopeheights[s][0]);
							Plane p = new Plane(center, angle, -s.FloorSlope.GetAngleZ(), true);
							s.FloorSlope = p.Normal;
							s.FloorSlopeOffset = p.Offset;
						}

						// Update ceiling slope?
						if (s.CeilSlope.GetLengthSq() > 0 && !float.IsNaN(s.CeilSlopeOffset / s.CeilSlope.z))
						{
							float angle = s.CeilSlope.GetAngleXY() + rotation + Angle2D.PIHALF;
							// Not sure what the logic should be for flipping horizintally and/or vertically
							//if (size.x < 0.0f) angle += Angle2D.PI;
							//if (size.y < 0.0f) angle += Angle2D.PI;

							Vector3D center = new Vector3D(s.BBox.X + s.BBox.Width / 2, s.BBox.Y + s.BBox.Height / 2, slopeheights[s][1]);
							Plane p = new Plane(center, angle, -s.CeilSlope.GetAngleZ(), false);
							s.CeilSlope = p.Normal;
							s.CeilSlopeOffset = p.Offset;
						}
					}
				}

				//mxd. Update floor/ceiling texture settings
				if (General.Map.UDMF) UpdateTextureTransform();
				
				General.Map.Map.Update(true, true);
				
				//mxd
				int oldoutsidefloorheight = int.MinValue;
				int oldoutsideceilingheight = int.MinValue;

				// When pasting, we want to join with the parent sector
				// where the sidedefs are referencing a virtual sector
				if(pasting)
				{
					Sector parent = null;
					Sector vsector = null;
					General.Settings.FindDefaultDrawSettings();

					// Go for all sidedes in the new geometry
					List<Sidedef> newsides = General.Map.Map.GetMarkedSidedefs(true);
					List<Linedef> oldlines = General.Map.Map.GetMarkedLinedefs(false); //mxd

					//mxd. Let's use a blockmap...
					RectangleF area = MapSet.CreateArea(oldlines);
					BlockMap<BlockEntry> blockmap = new BlockMap<BlockEntry>(area);
					blockmap.AddLinedefsSet(oldlines);

					foreach(Sidedef s in newsides) 
					{
						// Connected to a virtual sector?
						if(s.Marked && s.Sector.Fields.ContainsKey(MapSet.VirtualSectorField))
						{
							bool joined = false;
							
							// Keep reference to virtual sector
							vsector = s.Sector;
							
							// Not virtual on both sides?
							// Pascal 3-1-08: I can't remember why I have this check here, but it causes problems when
							// pasting a single linedef that refers to the same sector on both sides (the line then
							// loses both its sidedefs because it doesn't join any sector)
							//if((s.Other != null) && !s.Other.Sector.Fields.ContainsKey(MapSet.VirtualSectorField))
							{
								// Find out in which sector this was pasted
								Vector2D testpoint = s.Line.GetSidePoint(!s.IsFront);
								Linedef nl = MapSet.NearestLinedef(blockmap, testpoint); //mxd
								if(nl != null) 
								{
									Sidedef joinsidedef = (nl.SideOfLine(testpoint) <= 0 ? nl.Front : nl.Back);

									// Join?
									if(joinsidedef != null)
									{
										// Join!
										s.SetSector(joinsidedef.Sector);
										s.Marked = false;
										joined = true;

										// If we have no parent sector yet, then this is it!
										if(parent == null) parent = joinsidedef.Sector;
									}
								}
							}
							
							// Not joined any sector?
							if(!joined)
							{
								Linedef l = s.Line;

								// Remove the sidedef
								s.Dispose();

								// Correct the linedef
								if((l.Front == null) && (l.Back != null))
								{
									l.FlipVertices();
									l.FlipSidedefs();
								}

								// Correct the sided flags
								l.ApplySidedFlags();
							}
						}
					}
					
					// Do we have a virtual and parent sector?
					if((vsector != null) && (parent != null))
					{
						//mxd. Store floor/ceiling height
						oldoutsidefloorheight = vsector.FloorHeight;
						oldoutsideceilingheight = vsector.CeilHeight;
					}
					
					// Remove any virtual sectors
					General.Map.Map.RemoveVirtualSectors();
				}
				else
				{
					//mxd. Get floor/ceiling height from outside sectors
					if(unstablelines.Count == 0 && heightadjustmode != HeightAdjustMode.NONE)
					{
						// Get affected sectors
						HashSet<Sector> affectedsectors = new HashSet<Sector>(General.Map.Map.GetSelectedSectors(true));
						
						Point outsideheights = GetOutsideHeights(affectedsectors);
						oldoutsidefloorheight = outsideheights.X;
						oldoutsideceilingheight = outsideheights.Y;
					}
				}

				//mxd. We'll need sidedefs marked by StitchGeometry, not all sidedefs from selection...
				General.Map.Map.ClearMarkedSidedefs(false);

				// Snap to map format accuracy. We need to do that before stitching geometry because vertices that are very very slightly off the grid (like 0.00001) can
				// cause problems with BlockMapGetBlockCoordinates in the 32bit version
				General.Map.Map.SnapAllToAccuracy(General.Map.UDMF && usepreciseposition);

				// Stitch geometry
				General.Map.Map.StitchGeometry(General.Settings.MergeGeometryMode);

				// Snap to map format accuracy
				General.Map.Map.SnapAllToAccuracy(General.Map.UDMF && usepreciseposition);

				//mxd. Get new lines from linedef marks...
				HashSet<Linedef> newlines = new HashSet<Linedef>(General.Map.Map.GetMarkedLinedefs(true));

				//mxd. Marked lines were created during linedef splitting
				HashSet<Linedef> changedlines = new HashSet<Linedef>(selectedlines);
				changedlines.UnionWith(newlines);

				//mxd. Update sector height?
				if(changedlines.Count > 0 && heightadjustmode != HeightAdjustMode.NONE 
					&& oldoutsidefloorheight != int.MinValue && oldoutsideceilingheight != int.MinValue)
				{
					// Sectors may've been created/removed when applying dragging...
					HashSet<Sector> draggedsectors = new HashSet<Sector>(General.Map.Map.GetMarkedSectors(true));
					foreach(Sector ss in selectedsectors.Keys) if(!ss.IsDisposed) draggedsectors.Add(ss);

					// Change floor/ceiling height
					AdjustSectorsHeight(draggedsectors, heightadjustmode, oldoutsidefloorheight, oldoutsideceilingheight);
				}
				
				// Update cached values
				General.Map.Data.UpdateUsedTextures();
				General.Map.Map.Update();
				General.Map.ThingsFilter.Update();
				
				// Make normal selection?
				General.Map.Map.ClearAllSelected();
				if(!clearselection) //mxd
				{
					foreach(Vertex v in selectedvertices) if(!v.IsDisposed) v.Selected = true;
					foreach(Linedef l in selectedlines) { if(!l.IsDisposed) { l.Start.Selected = true; l.End.Selected = true; } }
					foreach(Thing t in selectedthings) if(!t.IsDisposed) t.Selected = true;
				}
				General.Map.Map.SelectionType = SelectionType.Vertices | SelectionType.Things;
				
				// Done
				selectedvertices = new List<Vertex>();
				selectedthings = new List<Thing>();
				selectedlines = new List<Linedef>();
				Cursor.Current = Cursors.Default;
				General.Map.IsChanged = true;
			}
			
			if(!modealreadyswitching)
			{
				// Return to previous stable mode
				General.Editing.ChangeMode(General.Editing.PreviousStableMode.Name);
			}
		}
		
		// Mode disengages
		public override void OnDisengage()
		{
			base.OnDisengage();

			// Remove toolbar buttons
			General.Interface.BeginToolbarUpdate(); //mxd
			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.FlipSelectionH);
			General.Interface.RemoveButton(BuilderPlug.Me.MenusForm.FlipSelectionV);
			General.Interface.EndToolbarUpdate(); //mxd

			//mxd. Save EditPanel-related settings 
			General.Settings.WritePluginSetting("editselectionmode.usepreciseposition", usepreciseposition);
			General.Settings.WritePluginSetting("editselectionmode.heightadjustmode", (int)heightadjustmode);

			// Remove docker
			General.Interface.RemoveDocker(docker);
			panel.Dispose();
			panel = null;
			
			// When not cancelled manually, we assume it is accepted
			if(!cancelled)
			{
				modealreadyswitching = true;
				//this.OnAccept();	// BAD! Any other plugins won't know this mode was accepted
				General.Editing.AcceptMode();
			}

			// Update
			General.Map.ThingsFilter.Update();
			General.Interface.RedrawDisplay();
			
			// Hide highlight info
			General.Interface.HideInfo();
			General.Interface.SetCursor(Cursors.Default);
		}

		// This redraws the display
		public override void OnRedrawDisplay()
		{
			UpdateRectangleComponents();

			renderer.RedrawSurface();

			// Render lines
			if(renderer.StartPlotter(true))
			{
				renderer.PlotLinedefSet(General.Map.Map.Linedefs);
				renderer.PlotVerticesSet(General.Map.Map.Vertices);
				if(highlighted is Vertex) renderer.PlotVertex((Vertex)highlighted, ColorCollection.HIGHLIGHT);
				renderer.Finish();
			}

			// Render things
			if(renderer.StartThings(true))
			{
				renderer.RenderThingSet(General.Map.ThingsFilter.HiddenThings, General.Settings.HiddenThingsAlpha);
				renderer.RenderThingSet(General.Map.ThingsFilter.VisibleThings, General.Settings.ActiveThingsAlpha);
				if(highlighted is Thing) renderer.RenderThing((Thing)highlighted, General.Colors.Highlight, General.Settings.ActiveThingsAlpha);
				renderer.Finish();
			}

			// Render selection
			if(renderer.StartOverlay(true))
			{
				// Rectangle
				PixelColor rectcolor = General.Colors.Highlight.WithAlpha(RECTANGLE_ALPHA);
				renderer.RenderGeometry(cornerverts, null, true);
				renderer.RenderLine(corners[0], corners[1], 4, rectcolor, true);
				renderer.RenderLine(corners[1], corners[2], 4, rectcolor, true);
				renderer.RenderLine(corners[2], corners[3], 4, rectcolor, true);
				renderer.RenderLine(corners[3], corners[0], 4, rectcolor, true);
				
				// Extension line
				if(extensionline.GetLengthSq() > 0.0f)
					renderer.RenderLine(extensionline.v1, extensionline.v2, 1, General.Colors.Indication.WithAlpha(EXTENSION_LINE_ALPHA), true);
				
				// Grips
				for(int i = 0; i < 4; i++)
				{
					renderer.RenderRectangleFilled(resizegrips[i], General.Colors.Background, true);
					renderer.RenderRectangle(resizegrips[i], 2, General.Colors.Highlight, true);
					renderer.RenderRectangleFilled(rotategrips[i], General.Colors.Background, true);
					renderer.RenderRectangle(rotategrips[i], 2, General.Colors.Indication, true);
				}

				renderer.Finish();
			}

			renderer.Present();
		}
		
		// Mouse moves
		public override void OnMouseMove(MouseEventArgs e)
		{
			base.OnMouseMove(e);
			if(panning) return; //mxd. Skip all this jazz while panning
			Update();
		}

		// Mouse leaves the display
		public override void OnMouseLeave(EventArgs e)
		{
			base.OnMouseLeave(e);
			
			// Reset cursor
			General.Interface.SetCursor(Cursors.Default);
		}

		// When edit button is pressed
		protected override void OnEditBegin()
		{
			base.OnEditBegin();
			OnSelectBegin();
		}

		// When edit button is released
		protected override void OnEditEnd()
		{
			base.OnEditEnd();
			OnSelectEnd();
		}

		// When select button is pressed
		protected override void OnSelectBegin()
		{
			base.OnSelectBegin();

			if(mode != ModifyMode.None) return;

			// Used in many cases:
			Vector2D center = offset + size * 0.5f;
			Vector2D delta;

			// Check what grip the mouse is over
			Grip mousegrip = (autodrag ? Grip.Main : CheckMouseGrip()); //mxd. We only want to move when starting auto-dragging
			switch(mousegrip)
			{
				// Drag main rectangle
				case Grip.Main:
					
					// Find the original position of the highlighted element
					if(highlighted is Vertex)
					{
						int index = 0;
						foreach(Vertex v in selectedvertices)
						{
							if(v == highlighted)
							{
								highlightedpos = vertexpos[index];
								break;
							}
							index++;
						}
					}
					else if(highlighted is Thing)
					{
						int index = 0;
						foreach(Thing t in selectedthings)
						{
							if(t == highlighted)
							{
								highlightedpos = thingpos[index];
								break;
							}
							index++;
						}
					}
					
					dragoffset = mousemappos - offset;
					mode = ModifyMode.Dragging;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Resize
				case Grip.SizeN:

					// The resize vector is a unit vector in the direction of the resize.
					// We multiply this with the sign of the current size, because the
					// corners may be reversed when the selection is flipped.
					resizevector = corners[1] - corners[2];
					resizevector = resizevector.GetNormal() * Math.Sign(size.y);
					
					// The edgevector is a vector with length and direction of the edge perpendicular to the resizevector
					edgevector = corners[1] - corners[0];
					
					// Make the resize axis. This is a line with the length and direction
					// of basesize used to calculate the resize percentage.
					resizeaxis = new Line2D(corners[2], corners[2] + resizevector * basesize.y);

					// Original axis filter
					resizefilter = new Vector2D(0.0f, 1.0f);

					// This is the corner that must stay in the same position
					stickcorner = 2;

					Highlight(null);
					mode = ModifyMode.Resizing;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Resize
				case Grip.SizeE:
					// See description above
					resizevector = corners[1] - corners[0];
					resizevector = resizevector.GetNormal() * Math.Sign(size.x);
					edgevector = corners[1] - corners[2];
					resizeaxis = new Line2D(corners[0], corners[0] + resizevector * basesize.x);
					resizefilter = new Vector2D(1.0f, 0.0f);
					stickcorner = 0;
					Highlight(null);
					mode = ModifyMode.Resizing;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Resize
				case Grip.SizeS:
					// See description above
					resizevector = corners[2] - corners[1];
					resizevector = resizevector.GetNormal() * Math.Sign(size.y);
					edgevector = corners[2] - corners[3];
					resizeaxis = new Line2D(corners[1], corners[1] + resizevector * basesize.y);
					resizefilter = new Vector2D(0.0f, 1.0f);
					stickcorner = 0;
					Highlight(null);
					mode = ModifyMode.Resizing;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Resize
				case Grip.SizeW:
					// See description above
					resizevector = corners[0] - corners[1];
					resizevector = resizevector.GetNormal() * Math.Sign(size.x);
					edgevector = corners[0] - corners[3];
					resizeaxis = new Line2D(corners[1], corners[1] + resizevector * basesize.x);
					resizefilter = new Vector2D(1.0f, 0.0f);
					stickcorner = 1;
					Highlight(null);
					mode = ModifyMode.Resizing;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Rotate
				case Grip.RotateLB:
					delta = corners[3] - center;
					rotategripangle = delta.GetAngle() - rotation;
					Highlight(null);
					mode = ModifyMode.Rotating;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Rotate
				case Grip.RotateLT:
					delta = corners[0] - center;
					rotategripangle = delta.GetAngle() - rotation;
					Highlight(null);
					mode = ModifyMode.Rotating;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Rotate
				case Grip.RotateRB:
					delta = corners[2] - center;
					rotategripangle = delta.GetAngle() - rotation;
					Highlight(null);
					mode = ModifyMode.Rotating;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Rotate
				case Grip.RotateRT:
					delta = corners[1] - center;
					rotategripangle = delta.GetAngle() - rotation;
					Highlight(null);
					mode = ModifyMode.Rotating;

					EnableAutoPanning();
					autopanning = true;
					break;

				// Outside the selection?
				default:
					// Accept and be done with it
					General.Editing.AcceptMode();
					break;
			}
		}

		// When selected button is released
		protected override void OnSelectEnd()
		{
			base.OnSelectEnd();
			
			// Remove extension line
			extensionline = new Line2D();

			if(autopanning)
			{
				DisableAutoPanning();
				autopanning = false;
			}
			
			// No modifying mode
			mode = ModifyMode.None;

			//mxd. Update floor/ceiling texture settings
			if(General.Map.UDMF) UpdateTextureTransform();
			
			// Redraw
			General.Map.Map.Update();
			General.Interface.RedrawDisplay();
		}

		// When a key is released
		public override void OnKeyUp(KeyEventArgs e)
		{
			base.OnKeyUp(e);
			if((snaptogrid != (General.Interface.ShiftState ^ General.Interface.SnapToGrid)) ||
			   (snaptonearest != (General.Interface.CtrlState ^ General.Interface.AutoMerge))) Update();
		}

		// When a key is pressed
		public override void OnKeyDown(KeyEventArgs e)
		{
			base.OnKeyDown(e);
			if((snaptogrid != (General.Interface.ShiftState ^ General.Interface.SnapToGrid)) ||
			   (snaptonearest != (General.Interface.CtrlState ^ General.Interface.AutoMerge))) Update();
		}

		
		
		#endregion

		#region ================== Actions

		// This clears the selection
		[BeginAction("clearselection", BaseAction = true)]
		public void ClearSelection()
		{
			//mxd. Accept changes
			clearselection = true;
			General.Editing.AcceptMode();

			//mxd. Clear selection info
			General.Interface.DisplayStatus(StatusType.Selection, string.Empty);
		}

		// Flip vertically
		[BeginAction("flipselectionv")]
		public void FlipVertically()
		{
			// Flip the selection
			offset.y += size.y;
			size.y = -size.y;
			
			// Update
			UpdateGeometry();
			UpdateRectangleComponents();
			General.Map.Map.Update();
			General.Interface.RedrawDisplay();
		}

		// Flip horizontally
		[BeginAction("flipselectionh")]
		public void FlipHorizontally()
		{
			// Flip the selection
			offset.x += size.x;
			size.x = -size.x;

			// Update
			UpdateGeometry();
			UpdateRectangleComponents();
			General.Map.Map.Update();
			General.Interface.RedrawDisplay();
		}

		#endregion
	}
}