#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.Globalization;
using System.Drawing;
using CodeImp.DoomBuilder.Map;
using SlimDX.Direct3D9;
using SlimDX;
using CodeImp.DoomBuilder.Geometry;
using CodeImp.DoomBuilder.Data;
using CodeImp.DoomBuilder.Editing;
using CodeImp.DoomBuilder.GZBuilder.Data; //mxd
using CodeImp.DoomBuilder.GZBuilder.Geometry; //mxd
using CodeImp.DoomBuilder.Config; //mxd

#endregion

namespace CodeImp.DoomBuilder.Rendering
{

	/* This renders a 2D presentation of the map. This is done in several
	 * layers which each are optimized for a different purpose. Set the
	 * PresentationLayer(s) to specify how to present these layers.
	 */

	internal sealed class Renderer2D : Renderer, IRenderer2D
	{
		#region ================== Constants

		private const float FSAA_FACTOR = 0.6f;
		private const float THING_ARROW_SIZE = 1.5f;
		private const float THING_ARROW_SHRINK = 2f;
		private const float THING_CIRCLE_SIZE = 1f;
		private const float THING_SPRITE_SHRINK = 2f;
		private const int THING_BUFFER_SIZE = 100;
		private const float MINIMUM_THING_RADIUS = 1.5f; //mxd
		private const float MINIMUM_SPRITE_RADIUS = 5.5f; //mxd

		private const string FONT_NAME = "Verdana";
		private const int FONT_WIDTH = 0;
		private const int FONT_HEIGHT = 0;

		private const int NUM_THING_TEXTURES = 2;
		internal const int NUM_VIEW_MODES = 4;
		
		#endregion

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

		// Rendertargets
		private Texture backtex;
		private Texture plottertex;
		private Texture thingstex;
		private Texture overlaytex;
		private Texture surfacetex;

		// Locking data
		private DataRectangle plotlocked;
		private Surface targetsurface;

		// Rendertarget sizes
		private Size windowsize;
		private Size structsize;
		private Size thingssize;
		private Size overlaysize;
		private Size backsize;
		
		// Font
		private SlimDX.Direct3D9.Font font;

		// Geometry plotter
		private Plotter plotter;

		// Vertices to present the textures
		private VertexBuffer screenverts;
		private FlatVertex[] backimageverts;
		
		// Batch buffer for things rendering
		private VertexBuffer thingsvertices;
		
		// Render settings
		private int vertexsize;
		private RenderLayers renderlayer = RenderLayers.None;
		
		// Surfaces
		private SurfaceManager surfaces;
		
		// Images
		private ResourceImage[] thingtexture;
		
		// View settings (world coordinates)
		private ViewMode viewmode;
		private float scale;
		private float scaleinv;
		private float offsetx;
		private float offsety;
		private float translatex;
		private float translatey;
		private float linenormalsize;
		private float lastgridscale = -1f;
		private int lastgridsize;
		private float lastgridx;
		private float lastgridy;
		private RectangleF viewport;
		private RectangleF yviewport;

		// Presentation
		private Presentation present;
		
		#endregion

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

		public float OffsetX { get { return offsetx; } }
		public float OffsetY { get { return offsety; } }
		public float TranslateX { get { return translatex; } }
		public float TranslateY { get { return translatey; } }
		public float Scale { get { return scale; } }
		public int VertexSize { get { return vertexsize; } }
		public ViewMode ViewMode { get { return viewmode; } }
		public SurfaceManager Surfaces { get { return surfaces; } }
		public RectangleF Viewport { get { return viewport; } } //mxd
		new public bool FullBrightness { get { return fullbrightness; } set { fullbrightness = value; } } //mxd

		#endregion

		#region ================== Constructor / Disposer
		
		// Constructor
		internal Renderer2D(D3DDevice graphics) : base(graphics)
		{
			// Load thing textures
			thingtexture = new ResourceImage[NUM_THING_TEXTURES];
			for(int i = 0; i < NUM_THING_TEXTURES; i++)
			{
				thingtexture[i] = new ResourceImage("CodeImp.DoomBuilder.Resources.Thing2D_" + i.ToString(CultureInfo.InvariantCulture) + ".png");
				thingtexture[i].UseColorCorrection = false;
				thingtexture[i].LoadImage();
				thingtexture[i].CreateTexture();
			}

			// Create surface manager
			surfaces = new SurfaceManager();

			// Create rendertargets
			CreateRendertargets();
			
			// We have no destructor
			GC.SuppressFinalize(this);
		}

		// Disposer
		internal override void Dispose()
		{
			// Not already disposed?
			if(!isdisposed)
			{
				// Destroy rendertargets
				DestroyRendertargets();
				foreach(ResourceImage i in thingtexture) i.Dispose();
				
				// Dispose surface manager
				surfaces.Dispose();
				
				// Done
				base.Dispose();
			}
		}

		#endregion

		#region ================== Presenting

		// This sets the presentation to use
		public void SetPresentation(Presentation present)
		{
			this.present = new Presentation(present);
		}
		
		// This draws the image on screen
		public unsafe void Present()
		{
			General.Plugins.OnPresentDisplayBegin();
			
			// Start drawing
			if(graphics.StartRendering(true, General.Colors.Background.ToColorValue(), graphics.BackBuffer, graphics.DepthBuffer))
			{
				// Renderstates that count for this whole sequence
				graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
				graphics.Device.SetRenderState(RenderState.ZEnable, false);
				graphics.Device.SetRenderState(RenderState.FogEnable, false);
				graphics.Device.SetStreamSource(0, screenverts, 0, sizeof(FlatVertex));
				graphics.Device.SetTransform(TransformState.World, Matrix.Identity);
				graphics.Shaders.Display2D.Begin();

				// Go for all layers
				foreach(PresentLayer layer in present.layers)
				{
					int aapass;

					// Set blending mode
					switch(layer.blending)
					{
						case BlendingMode.None:
							graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
							graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
							graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
							break;

						case BlendingMode.Mask:
							graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
							graphics.Device.SetRenderState(RenderState.AlphaTestEnable, true);
							graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
							break;

						case BlendingMode.Alpha:
							graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, true);
							graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
							graphics.Device.SetRenderState(RenderState.SourceBlend, Blend.SourceAlpha);
							graphics.Device.SetRenderState(RenderState.DestinationBlend, Blend.InverseSourceAlpha);
							graphics.Device.SetRenderState(RenderState.TextureFactor, (new Color4(layer.alpha, 1f, 1f, 1f)).ToArgb());
							break;

						case BlendingMode.Additive:
							graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, true);
							graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
							graphics.Device.SetRenderState(RenderState.SourceBlend, Blend.SourceAlpha);
							graphics.Device.SetRenderState(RenderState.DestinationBlend, Blend.One);
							graphics.Device.SetRenderState(RenderState.TextureFactor, (new Color4(layer.alpha, 1f, 1f, 1f)).ToArgb());
							break;
					}

					// Check which pass to use
					if(layer.antialiasing && General.Settings.QualityDisplay) aapass = 0; else aapass = 1;

					// Render layer
					switch(layer.layer)
					{
						// BACKGROUND
						case RendererLayer.Background:
							if((backimageverts == null) || (General.Map.Grid.Background.Texture == null)) break;
							graphics.Device.SetTexture(0, General.Map.Grid.Background.Texture);
							graphics.Shaders.Display2D.Texture1 = General.Map.Grid.Background.Texture;
							graphics.Shaders.Display2D.SetSettings(1f / windowsize.Width, 1f / windowsize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawUserPrimitives<FlatVertex>(PrimitiveType.TriangleStrip, 0, 2, backimageverts);
							graphics.Shaders.Display2D.EndPass();
							graphics.Device.SetStreamSource(0, screenverts, 0, sizeof(FlatVertex));
							break;

						// GRID
						case RendererLayer.Grid:
							graphics.Device.SetTexture(0, backtex);
							graphics.Shaders.Display2D.Texture1 = backtex;
							graphics.Shaders.Display2D.SetSettings(1f / backsize.Width, 1f / backsize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
							graphics.Shaders.Display2D.EndPass();
							break;

						// GEOMETRY
						case RendererLayer.Geometry:
							graphics.Device.SetTexture(0, plottertex);
							graphics.Shaders.Display2D.Texture1 = plottertex;
							graphics.Shaders.Display2D.SetSettings(1f / structsize.Width, 1f / structsize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
							graphics.Shaders.Display2D.EndPass();
							break;

						// THINGS
						case RendererLayer.Things:
							graphics.Device.SetTexture(0, thingstex);
							graphics.Shaders.Display2D.Texture1 = thingstex;
							graphics.Shaders.Display2D.SetSettings(1f / thingssize.Width, 1f / thingssize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
							graphics.Shaders.Display2D.EndPass();
							break;

						// OVERLAY
						case RendererLayer.Overlay:
							graphics.Device.SetTexture(0, overlaytex);
							graphics.Shaders.Display2D.Texture1 = overlaytex;
							graphics.Shaders.Display2D.SetSettings(1f / overlaysize.Width, 1f / overlaysize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
							graphics.Shaders.Display2D.EndPass();
							break;

						// SURFACE
						case RendererLayer.Surface:
							graphics.Device.SetTexture(0, surfacetex);
							graphics.Shaders.Display2D.Texture1 = surfacetex;
							graphics.Shaders.Display2D.SetSettings(1f / overlaysize.Width, 1f / overlaysize.Height, FSAA_FACTOR, layer.alpha, false);
							graphics.Shaders.Display2D.BeginPass(aapass);
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
							graphics.Shaders.Display2D.EndPass();
							break;
					}
				}

				// Done
				graphics.Shaders.Display2D.End();
				graphics.FinishRendering();
				graphics.Present();

				// Release binds
				graphics.Device.SetTexture(0, null);
				graphics.Shaders.Display2D.Texture1 = null;
				graphics.Device.SetStreamSource(0, null, 0, 0);
			}
			else
			{
				// Request delayed redraw
				General.MainWindow.DelayedRedraw();
			}
		}
		
		#endregion

		#region ================== Management

		// This is called before a device is reset
		// (when resized or display adapter was changed)
		public override void UnloadResource()
		{
			// Destroy rendertargets
			DestroyRendertargets();
		}
		
		// This is called resets when the device is reset
		// (when resized or display adapter was changed)
		public override void ReloadResource()
		{
			// Re-create rendertargets
			CreateRendertargets();
		}

		// This resets the graphics
		public override void Reset()
		{
			UnloadResource();
			ReloadResource();
		}

		// This destroys the rendertargets
		public void DestroyRendertargets()
		{
			// Trash rendertargets
			if(plottertex != null) plottertex.Dispose();
			if(thingstex != null) thingstex.Dispose();
			if(overlaytex != null) overlaytex.Dispose();
			if(surfacetex != null) surfacetex.Dispose();
			if(backtex != null) backtex.Dispose();
			if(screenverts != null) screenverts.Dispose();
			plottertex = null;
			thingstex = null;
			backtex = null;
			screenverts = null;
			overlaytex = null;
			surfacetex = null;
			
			// Trash things batch buffer
			if(thingsvertices != null) thingsvertices.Dispose();
			thingsvertices = null;
			lastgridscale = -1f;
			lastgridsize = 0;

			// Trash font
			if(font != null) font.Dispose();
			font = null;
		}
		
		// Allocates new image memory to render on
		public unsafe void CreateRendertargets()
		{
			SurfaceDescription sd;
			DataStream stream;
			FlatVertex[] verts;
			
			// Destroy rendertargets
			DestroyRendertargets();
			
			// Get new width and height
			windowsize.Width = graphics.RenderTarget.ClientSize.Width;
			windowsize.Height = graphics.RenderTarget.ClientSize.Height;

			// Create rendertargets textures
			plottertex = new Texture(graphics.Device, windowsize.Width, windowsize.Height, 1, Usage.None, Format.A8R8G8B8, Pool.Managed);
			thingstex = new Texture(graphics.Device, windowsize.Width, windowsize.Height, 1, Usage.RenderTarget, Format.A8R8G8B8, Pool.Default);
			backtex = new Texture(graphics.Device, windowsize.Width, windowsize.Height, 1, Usage.None, Format.A8R8G8B8, Pool.Managed);
			overlaytex = new Texture(graphics.Device, windowsize.Width, windowsize.Height, 1, Usage.RenderTarget, Format.A8R8G8B8, Pool.Default);
			surfacetex = new Texture(graphics.Device, windowsize.Width, windowsize.Height, 1, Usage.RenderTarget, Format.A8R8G8B8, Pool.Default);
			
			// Get the real surface sizes
			sd = plottertex.GetLevelDescription(0);
			structsize.Width = sd.Width;
			structsize.Height = sd.Height;
			sd = thingstex.GetLevelDescription(0);
			thingssize.Width = sd.Width;
			thingssize.Height = sd.Height;
			sd = backtex.GetLevelDescription(0);
			backsize.Width = sd.Width;
			backsize.Height = sd.Height;
			sd = overlaytex.GetLevelDescription(0);
			overlaysize.Width = sd.Width;
			overlaysize.Height = sd.Height;
			
			// Clear rendertargets
			// This may cause a crash when resetting because it recursively
			// calls Reset in the Start functions and doesn't get to Finish
			//StartPlotter(true); Finish();
			//StartThings(true); Finish();
			//StartOverlay(true); Finish();
			graphics.ClearRendertarget(General.Colors.Background.WithAlpha(0).ToColorValue(), thingstex.GetSurfaceLevel(0), null);
			graphics.ClearRendertarget(General.Colors.Background.WithAlpha(0).ToColorValue(), overlaytex.GetSurfaceLevel(0), null);
			
			// Create font
			font = new SlimDX.Direct3D9.Font(graphics.Device, FONT_WIDTH, FONT_HEIGHT, FontWeight.Bold, 1, false, CharacterSet.Ansi, Precision.Default, FontQuality.Antialiased, PitchAndFamily.Default, FONT_NAME);
			
			// Create vertex buffers
			screenverts = new VertexBuffer(graphics.Device, 4 * sizeof(FlatVertex), Usage.Dynamic | Usage.WriteOnly, VertexFormat.None, Pool.Default);
			thingsvertices = new VertexBuffer(graphics.Device, THING_BUFFER_SIZE * 12 * sizeof(FlatVertex), Usage.Dynamic | Usage.WriteOnly, VertexFormat.None, Pool.Default);

			// Make screen vertices
			stream = screenverts.Lock(0, 4 * sizeof(FlatVertex), LockFlags.Discard | LockFlags.NoSystemLock);
			verts = CreateScreenVerts(structsize);
			stream.WriteRange<FlatVertex>(verts);
			screenverts.Unlock();
			stream.Dispose();
			
			// Force update of view
			lastgridscale = -1f;
			lastgridsize = 0;
			lastgridx = 0.0f;
			lastgridy = 0.0f;
			UpdateTransformations();
		}

		// This makes screen vertices for display
		private static FlatVertex[] CreateScreenVerts(Size texturesize)
		{
			FlatVertex[] screenverts = new FlatVertex[4];
			screenverts[0].x = 0.5f;
			screenverts[0].y = 0.5f;
			screenverts[0].c = -1;
			screenverts[0].u = 1f / texturesize.Width;
			screenverts[0].v = 1f / texturesize.Height;
			screenverts[1].x = texturesize.Width - 1.5f;
			screenverts[1].y = 0.5f;
			screenverts[1].c = -1;
			screenverts[1].u = 1f - 1f / texturesize.Width;
			screenverts[1].v = 1f / texturesize.Height;
			screenverts[2].x = 0.5f;
			screenverts[2].y = texturesize.Height - 1.5f;
			screenverts[2].c = -1;
			screenverts[2].u = 1f / texturesize.Width;
			screenverts[2].v = 1f - 1f / texturesize.Height;
			screenverts[3].x = texturesize.Width - 1.5f;
			screenverts[3].y = texturesize.Height - 1.5f;
			screenverts[3].c = -1;
			screenverts[3].u = 1f - 1f / texturesize.Width;
			screenverts[3].v = 1f - 1f / texturesize.Height;
			return screenverts;
		}

		#endregion
		
		#region ================== View

		// This changes view mode
		public void SetViewMode(ViewMode mode)
		{
			viewmode = mode;
		}
		
		// This changes view position
		public void PositionView(float x, float y)
		{
			// Change position in world coordinates
			offsetx = x;
			offsety = y;
			UpdateTransformations();
		}
		
		// This changes zoom
		public void ScaleView(float scale)
		{
			// Change zoom scale
			this.scale = scale;
			UpdateTransformations();
			
			// Show zoom on main window
			General.MainWindow.UpdateZoom(scale);
		}

		// This updates some maths
		private void UpdateTransformations()
		{
			scaleinv = 1f / scale;
			translatex = -offsetx + (windowsize.Width * 0.5f) * scaleinv;
			translatey = -offsety - (windowsize.Height * 0.5f) * scaleinv;
			linenormalsize = 10f * scaleinv;

			vertexsize = (int)(1.7f * General.Settings.GZVertexScale2D * scale + 0.5f); //mxd. added GZVertexScale2D
			if(vertexsize < 0) vertexsize = 0;
			if(vertexsize > 4) vertexsize = 4;

			Matrix scaling = Matrix.Scaling((1f / windowsize.Width) * 2f, (1f / windowsize.Height) * -2f, 1f);
			Matrix translate = Matrix.Translation(-(float)windowsize.Width * 0.5f, -(float)windowsize.Height * 0.5f, 0f);
			graphics.Device.SetTransform(TransformState.View, Matrix.Multiply(translate, scaling));
			graphics.Device.SetTransform(TransformState.Projection, Matrix.Identity);
			Vector2D lt = DisplayToMap(new Vector2D(0.0f, 0.0f));
			Vector2D rb = DisplayToMap(new Vector2D(windowsize.Width, windowsize.Height));
			viewport = new RectangleF(lt.x, lt.y, rb.x - lt.x, rb.y - lt.y);
			yviewport = new RectangleF(lt.x, rb.y, rb.x - lt.x, lt.y - rb.y);
		}

		// This sets the world matrix for transformation
		private void SetWorldTransformation(bool transform)
		{
			if(transform)
			{
				Matrix translate = Matrix.Translation(translatex, translatey, 0f);
				Matrix scaling = Matrix.Scaling(scale, -scale, 1f);
				graphics.Device.SetTransform(TransformState.World, Matrix.Multiply(translate, scaling));
			}
			else
			{
				graphics.Device.SetTransform(TransformState.World, Matrix.Identity);
			}
		}
		
		/// <summary>
		/// This unprojects display coordinates (screen space) to map coordinates
		/// </summary>
		public Vector2D DisplayToMap(Vector2D mousepos)
		{
			return mousepos.GetInvTransformed(-translatex, -translatey, scaleinv, -scaleinv);
		}
		
		/// <summary>
		/// This projects map coordinates to display coordinates (screen space)
		/// </summary>
		public Vector2D MapToDisplay(Vector2D mappos)
		{
			return mappos.GetTransformed(translatex, translatey, scale, -scale);
		}
		
		#endregion

		#region ================== Colors

		// This returns the color for a thing
		public PixelColor DetermineThingColor(Thing t)
		{
			// Determine color
			if (t.Selected) return General.Colors.Selection;
		   
			//mxd. if thing is light, set it's color to light color:
			if(Array.IndexOf(GZBuilder.GZGeneral.GZ_LIGHTS, t.Type) != -1)
			{
				if (t.Type == 1502) //vavoom light
					return new PixelColor(255, 255, 255, 255);
				if (t.Type == 1503) //vavoom colored light
					return new PixelColor(255, (byte)t.Args[1], (byte)t.Args[2], (byte)t.Args[3]);
				return new PixelColor(255, (byte)t.Args[0], (byte)t.Args[1], (byte)t.Args[2]);
			}

			return t.Color;
		}

		// This returns the color for a vertex
		public int DetermineVertexColor(Vertex v)
		{
			// Determine color
			if(v.Selected) return ColorCollection.SELECTION;
			return ColorCollection.VERTICES;
		}

		// This returns the color for a linedef
		public PixelColor DetermineLinedefColor(Linedef l)
		{
			if(l.Selected) return General.Colors.Selection;

			//mxd. Impassable lines
			if(l.ImpassableFlag) 
			{
				if(l.ColorPresetIndex != -1)
					return General.Map.ConfigSettings.LinedefColorPresets[l.ColorPresetIndex].Color;
				return General.Colors.Linedefs;
			}

			//mxd. Passable lines
			if(l.ColorPresetIndex != -1)
				return General.Map.ConfigSettings.LinedefColorPresets[l.ColorPresetIndex].Color.WithAlpha(General.Settings.DoubleSidedAlphaByte);
			return General.Colors.Linedefs.WithAlpha(General.Settings.DoubleSidedAlphaByte);
		}

		//mxd. This collects indices of linedefs, which are parts of sectors with 3d floors
		public void UpdateExtraFloorFlag() 
		{
			List<int> tagList = new List<int>();
			
			//find lines with 3d floor action and collect sector tags
			foreach(Linedef l in General.Map.Map.Linedefs)
			{
				if(l.Action == 160) 
				{
					int sectortag = (l.Args[1] & 8) != 0 ? l.Args[0] : l.Args[0] + (l.Args[4] << 8);
					if(sectortag != 0) tagList.Add(sectortag);
				}
			}

			tagList.Sort();
			int[] tags = tagList.ToArray();

			//find lines, which are related to sectors with 3d floors, and collect their valuable indices
			foreach(Linedef l in General.Map.Map.Linedefs) 
			{
				if(l.Front != null && l.Front.Sector != null && l.Front.Sector.Tag != 0 && Array.BinarySearch(tags, l.Front.Sector.Tag) > -1) 
				{
					l.ExtraFloorFlag = true;
					continue;
				}
				if(l.Back != null && l.Back.Sector != null && l.Back.Sector.Tag != 0 && Array.BinarySearch(tags, l.Back.Sector.Tag) > -1) 
				{
					l.ExtraFloorFlag = true;
					continue;
				}

				l.ExtraFloorFlag = false;
			}
		}

		#endregion

		#region ================== Start / Finish

		// This begins a drawing session
		public unsafe bool StartPlotter(bool clear)
		{
			if(renderlayer != RenderLayers.None) return false; //mxd. Can't render. Most probably because previous frame or render layer wasn't finished yet.

			renderlayer = RenderLayers.Plotter;
			try { graphics.Device.SetRenderState(RenderState.FogEnable, false); } catch(Exception) { }
			
			// Rendertargets available?
			if(plottertex != null)
			{
				// Lock structures rendertarget memory
				plotlocked = plottertex.LockRectangle(0, LockFlags.NoSystemLock);

				// Create structures plotter
				plotter = new Plotter((PixelColor*)plotlocked.Data.DataPointer.ToPointer(), plotlocked.Pitch / sizeof(PixelColor), structsize.Height, structsize.Width, structsize.Height);

				// Redraw grid when structures image was cleared
				if(clear)
				{
					plotter.Clear();
					RenderBackgroundGrid();
					SetupBackground();
				}
				
				// Ready for rendering
				UpdateTransformations();
				return true;
			}

			// Can't render!
			Finish();
			return false;
		}

		// This begins a drawing session
		public bool StartThings(bool clear)
		{
			if(renderlayer != RenderLayers.None) return false;  //mxd. Can't render. Most probably because previous frame or render layer wasn't finished yet.

			renderlayer = RenderLayers.Things;
			try { graphics.Device.SetRenderState(RenderState.FogEnable, false); } catch(Exception) { }
			
			// Rendertargets available?
			if(thingstex != null)
			{
				// Set the rendertarget to the things texture
				targetsurface = thingstex.GetSurfaceLevel(0);
				if(graphics.StartRendering(clear, General.Colors.Background.WithAlpha(0).ToColorValue(), targetsurface, null))
				{
					// Ready for rendering
					UpdateTransformations();
					return true;
				}

				// Can't render!
				Finish();
				return false;
			}

			// Can't render!
			Finish();
			return false;
		}

		// This begins a drawing session
		public bool StartOverlay(bool clear)
		{
			if(renderlayer != RenderLayers.None) throw new InvalidOperationException("Renderer starting called before finished previous layer. Call Finish() first!");
			renderlayer = RenderLayers.Overlay;
			try { graphics.Device.SetRenderState(RenderState.FogEnable, false); } catch(Exception) { }
			
			// Rendertargets available?
			if(overlaytex != null)
			{
				// Set the rendertarget to the things texture
				targetsurface = overlaytex.GetSurfaceLevel(0);
				if(graphics.StartRendering(clear, General.Colors.Background.WithAlpha(0).ToColorValue(), targetsurface, null))
				{
					// Ready for rendering
					UpdateTransformations();
					return true;
				}

				// Can't render!
				Finish();
				return false;
			}

			// Can't render!
			Finish();
			return false;
		}

		// This ends a drawing session
		public void Finish()
		{
			// Clean up plotter
			if(renderlayer == RenderLayers.Plotter)
			{
				if(plottertex != null) plottertex.UnlockRectangle(0);
				if(plotlocked.Data != null) plotlocked.Data.Dispose();
				plotter = null;
			}
			
			// Clean up things / overlay
			if((renderlayer == RenderLayers.Things) || (renderlayer == RenderLayers.Overlay) || (renderlayer == RenderLayers.Surface))
			{
				// Stop rendering
				graphics.FinishRendering();
				
				// Release rendertarget
				try
				{
					graphics.Device.DepthStencilSurface = graphics.DepthBuffer;
					graphics.Device.SetRenderTarget(0, graphics.BackBuffer);
				}
				catch(Exception) { }
				if(targetsurface != null) targetsurface.Dispose();
				targetsurface = null;
			}
			
			// Done
			renderlayer = RenderLayers.None;
		}

		#endregion

		#region ================== Background

		// This sets up background image vertices
		private void SetupBackground()
		{
			// Only if a background image is set
			if((General.Map.Grid.Background != null) && !(General.Map.Grid.Background is UnknownImage))
			{
				Vector2D ltpos, rbpos;
				Vector2D backoffset = new Vector2D(General.Map.Grid.BackgroundX, General.Map.Grid.BackgroundY);
				Vector2D backimagesize = new Vector2D(General.Map.Grid.Background.ScaledWidth, General.Map.Grid.Background.ScaledHeight);
				Vector2D backimagescale = new Vector2D(General.Map.Grid.BackgroundScaleX, General.Map.Grid.BackgroundScaleY);

				// Scale the background image size
				backimagesize *= backimagescale;
				
				// Make vertices
				backimageverts = CreateScreenVerts(windowsize);

				// Determine map coordinates for view window
				ltpos = DisplayToMap(new Vector2D(0f, 0f));
				rbpos = DisplayToMap(new Vector2D(windowsize.Width, windowsize.Height));
				
				// Offset by given background offset
				ltpos -= backoffset;
				rbpos -= backoffset;
				
				// Calculate UV coordinates
				// NOTE: backimagesize.y is made negative to match Doom's coordinate system
				backimageverts[0].u = ltpos.x / backimagesize.x;
				backimageverts[0].v = ltpos.y / -backimagesize.y;
				backimageverts[1].u = rbpos.x / backimagesize.x;
				backimageverts[1].v = ltpos.y / -backimagesize.y;
				backimageverts[2].u = ltpos.x / backimagesize.x;
				backimageverts[2].v = rbpos.y / -backimagesize.y;
				backimageverts[3].u = rbpos.x / backimagesize.x;
				backimageverts[3].v = rbpos.y / -backimagesize.y;
			}
			else
			{
				// No background image
				backimageverts = null;
			}
		}

		// This renders all grid
		private unsafe void RenderBackgroundGrid()
		{
			Plotter gridplotter;
			DataRectangle lockedrect;
			
			// Do we need to redraw grid?
			if((lastgridsize != General.Map.Grid.GridSize) || (lastgridscale != scale) ||
			   (lastgridx != offsetx) || (lastgridy != offsety))
			{
				// Lock background rendertarget memory
				lockedrect = backtex.LockRectangle(0, LockFlags.NoSystemLock);

				// Create a plotter
				gridplotter = new Plotter((PixelColor*)lockedrect.Data.DataPointer.ToPointer(), lockedrect.Pitch / sizeof(PixelColor), backsize.Height, backsize.Width, backsize.Height);
				gridplotter.Clear();

				// Render normal grid
				RenderGrid(General.Map.Grid.GridSize, General.Colors.Grid, gridplotter);

				// Render 64 grid
				if(General.Map.Grid.GridSize <= 64) RenderGrid(64f, General.Colors.Grid64, gridplotter);

				//mxd. Render center of map
				int size = 16;
				Vector2D center = new Vector2D().GetTransformed(translatex, translatey, scale, -scale);
				int cx = (int)center.x;
				int cy = (int)center.y;
				PixelColor c = General.Colors.Highlight;
				gridplotter.DrawLineSolid(cx, cy + size, cx, cy - size, ref c);
				gridplotter.DrawLineSolid(cx - size, cy, cx + size, cy, ref c);

				// Done
				backtex.UnlockRectangle(0);
				lockedrect.Data.Dispose();
				lastgridscale = scale;
				lastgridsize = General.Map.Grid.GridSize;
				lastgridx = offsetx;
				lastgridy = offsety;
			}
		}
		
		// This renders the grid
		private void RenderGrid(float size, PixelColor c, Plotter gridplotter)
		{
			Vector2D ltpos, rbpos;
			Vector2D tlb, rbb;
			Vector2D pos = new Vector2D();
			float ystart, yend;
			float xstart, xend;
			float from, to;

			//mxd. Increase rendered grid size if needed
			if(size * scale <= 6f) do { size *= 2; } while(size * scale <= 6f);
			float sizeinv = 1f / size;

			// Determine map coordinates for view window
			ltpos = DisplayToMap(new Vector2D(0, 0));
			rbpos = DisplayToMap(new Vector2D(windowsize.Width, windowsize.Height));

			// Clip to nearest grid
			ltpos = GridSetup.SnappedToGrid(ltpos, size, sizeinv);
			rbpos = GridSetup.SnappedToGrid(rbpos, size, sizeinv);

			// Translate top left boundary and right bottom boundary of map to screen coords
			tlb = new Vector2D(General.Map.Config.LeftBoundary, General.Map.Config.TopBoundary).GetTransformed(translatex, translatey, scale, -scale);
			rbb = new Vector2D(General.Map.Config.RightBoundary, General.Map.Config.BottomBoundary).GetTransformed(translatex, translatey, scale, -scale);

			// Draw all horizontal grid lines
			ystart = rbpos.y > General.Map.Config.BottomBoundary ? rbpos.y : General.Map.Config.BottomBoundary;
			yend = ltpos.y < General.Map.Config.TopBoundary ? ltpos.y : General.Map.Config.TopBoundary;

			for(float y = ystart; y < yend + size; y += size) 
			{
				if(y > General.Map.Config.TopBoundary) y = General.Map.Config.TopBoundary;
				else if(y < General.Map.Config.BottomBoundary) y = General.Map.Config.BottomBoundary;

				from = tlb.x < 0 ? 0 : tlb.x;
				to = rbb.x > windowsize.Width ? windowsize.Width : rbb.x;

				pos.y = y;
				pos = pos.GetTransformed(translatex, translatey, scale, -scale);

				// Note: I'm not using Math.Ceiling in this case, because that doesn't work right.
				gridplotter.DrawGridLineH((int)pos.y, (int)Math.Round(from + 0.49999f), (int)Math.Round(to + 0.49999f), ref c);
			}

			// Draw all vertical grid lines
			xstart = ltpos.x > General.Map.Config.LeftBoundary ? ltpos.x : General.Map.Config.LeftBoundary;
			xend = rbpos.x < General.Map.Config.RightBoundary ? rbpos.x : General.Map.Config.RightBoundary;

			for(float x = xstart; x < xend + size; x += size) 
			{
				if(x > General.Map.Config.RightBoundary) x = General.Map.Config.RightBoundary;
				else if(x < General.Map.Config.LeftBoundary) x = General.Map.Config.LeftBoundary;

				from = tlb.y < 0 ? 0 : tlb.y;
				to = rbb.y > windowsize.Height ? windowsize.Height : rbb.y;

				pos.x = x;
				pos = pos.GetTransformed(translatex, translatey, scale, -scale);

				// Note: I'm not using Math.Ceiling in this case, because that doesn't work right.
				gridplotter.DrawGridLineV((int)pos.x, (int)Math.Round(from + 0.49999f), (int)Math.Round(to + 0.49999f), ref c);
			}
		}

		#endregion

		#region ================== Things

		// This makes vertices for a thing
		// Returns false when not on the screen
		private bool CreateThingBoxVerts(Thing t, ref FlatVertex[] verts, Dictionary<Thing, Vector2D> thingsByPosition, int offset, PixelColor c)
		{
			if(t.Size * scale < MINIMUM_THING_RADIUS) return false; //mxd. Don't render tiny little things

			// Determine size
			float circlesize = (t.FixedSize && (scale > 1.0f) ? t.Size * THING_CIRCLE_SIZE : t.Size * scale * THING_CIRCLE_SIZE);
			
			// Transform to screen coordinates
			Vector2D screenpos = ((Vector2D)t.Position).GetTransformed(translatex, translatey, scale, -scale);
			
			// Check if the thing is actually on screen
			if (((screenpos.x + circlesize) <= 0.0f) || ((screenpos.x - circlesize) >= windowsize.Width) ||
			    ((screenpos.y + circlesize) <= 0.0f) || ((screenpos.y - circlesize) >= windowsize.Height))
				return false;

			// Get integral color
			int color = c.ToInt();

			// Setup fixed rect for circle
			verts[offset].x = screenpos.x - circlesize;
			verts[offset].y = screenpos.y - circlesize;
			verts[offset].c = color;
			verts[offset].u = 0f;
			verts[offset].v = 0f;
			offset++;
			verts[offset].x = screenpos.x + circlesize;
			verts[offset].y = screenpos.y - circlesize;
			verts[offset].c = color;
			verts[offset].u = 0.5f;
			verts[offset].v = 0f;
			offset++;
			verts[offset].x = screenpos.x - circlesize;
			verts[offset].y = screenpos.y + circlesize;
			verts[offset].c = color;
			verts[offset].u = 0f;
			verts[offset].v = 1f;
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset].x = screenpos.x + circlesize;
			verts[offset].y = screenpos.y + circlesize;
			verts[offset].c = color;
			verts[offset].u = 0.5f;
			verts[offset].v = 1f;

			//mxd. Add to list
			thingsByPosition.Add(t, screenpos);

			// Done
			return true;
		}

		//mxd
		private void CreateThingArrowVerts(Thing t, ref FlatVertex[] verts, Vector2D screenpos, int offset) 
		{
			// Determine size
			float arrowsize = (t.FixedSize && (scale > 1.0f) ? (t.Size - THING_ARROW_SHRINK) * THING_ARROW_SIZE : (t.Size - THING_ARROW_SHRINK) * scale * THING_ARROW_SIZE);

			// Setup rotated rect for arrow
			float sinarrowsize = (float)Math.Sin(t.Angle + Angle2D.PI * 0.25f) * arrowsize;
			float cosarrowsize = (float)Math.Cos(t.Angle + Angle2D.PI * 0.25f) * arrowsize;

			verts[offset].x = screenpos.x + sinarrowsize;
			verts[offset].y = screenpos.y + cosarrowsize;
			verts[offset].c = -1;
			verts[offset].u = 0.51f;
			verts[offset].v = 0.01f;
			offset++;
			verts[offset].x = screenpos.x - cosarrowsize;
			verts[offset].y = screenpos.y + sinarrowsize;
			verts[offset].c = -1;
			verts[offset].u = 0.99f;
			verts[offset].v = 0.01f;
			offset++;
			verts[offset].x = screenpos.x + cosarrowsize;
			verts[offset].y = screenpos.y - sinarrowsize;
			verts[offset].c = -1;
			verts[offset].u = 0.51f;
			verts[offset].v = 0.99f;
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset].x = screenpos.x - sinarrowsize;
			verts[offset].y = screenpos.y - cosarrowsize;
			verts[offset].c = -1;
			verts[offset].u = 0.99f;
			verts[offset].v = 0.99f;
		}

		//mxd
		private static void CreateThingSpriteVerts(Vector2D screenpos, float width, float height, ref FlatVertex[] verts, int offset, int color) 
		{
			// Setup fixed rect for circle
			verts[offset].x = screenpos.x - width;
			verts[offset].y = screenpos.y - height;
			verts[offset].c = color;
			verts[offset].u = 0;
			verts[offset].v = 0;
			offset++;
			verts[offset].x = screenpos.x + width;
			verts[offset].y = screenpos.y - height;
			verts[offset].c = color;
			verts[offset].u = 1;
			verts[offset].v = 0;
			offset++;
			verts[offset].x = screenpos.x - width;
			verts[offset].y = screenpos.y + height;
			verts[offset].c = color;
			verts[offset].u = 0;
			verts[offset].v = 1;
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset] = verts[offset - 2];
			offset++;
			verts[offset].x = screenpos.x + width;
			verts[offset].y = screenpos.y + height;
			verts[offset].c = color;
			verts[offset].u = 1;
			verts[offset].v = 1;
		}
		
		// This draws a set of things
		private void RenderThingsBatch(ICollection<Thing> things, float alpha, bool fixedcolor, PixelColor c)
		{
			int thingtextureindex = 0;
			PixelColor tc;
			DataStream stream;
			
			// Anything to render?
			if(things.Count > 0)
			{
				// Make alpha color
				Color4 alphacolor = new Color4(alpha, 1.0f, 1.0f, 1.0f);
				
				// Set renderstates for things rendering
				graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
				graphics.Device.SetRenderState(RenderState.ZEnable, false);
				graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, true);
				graphics.Device.SetRenderState(RenderState.SourceBlend, Blend.SourceAlpha);
				graphics.Device.SetRenderState(RenderState.DestinationBlend, Blend.InverseSourceAlpha);
				graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
				graphics.Device.SetRenderState(RenderState.FogEnable, false);
				graphics.Device.SetRenderState(RenderState.TextureFactor, alphacolor.ToArgb());
				graphics.Device.SetStreamSource(0, thingsvertices, 0, FlatVertex.Stride);
				
				// Determine things texture to use
				if(General.Settings.SquareThings) thingtextureindex = 1;
				graphics.Device.SetTexture(0, thingtexture[thingtextureindex].Texture);
				graphics.Shaders.Things2D.Texture1 = thingtexture[thingtextureindex].Texture;
				SetWorldTransformation(false);
				graphics.Shaders.Things2D.SetSettings(alpha);
				
				// Begin drawing
				graphics.Shaders.Things2D.Begin();
				graphics.Shaders.Things2D.BeginPass(0);

				// Determine next lock size
				int locksize = (things.Count > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : things.Count;
				FlatVertex[] verts = new FlatVertex[THING_BUFFER_SIZE * 6];

				//mxd
				Dictionary<int, List<Thing>> thingsByType = new Dictionary<int, List<Thing>>();
				Dictionary<int, List<Thing>> modelsByType = new Dictionary<int, List<Thing>>();
				Dictionary<Thing, Vector2D> thingsByPosition = new Dictionary<Thing, Vector2D>();

				// Go for all things
				int buffercount = 0;
				int totalcount = 0;
				foreach(Thing t in things)
				{
					//collect models
					if (t.IsModel) 
					{
						if(!modelsByType.ContainsKey(t.Type)) modelsByType.Add(t.Type, new List<Thing>());
						modelsByType[t.Type].Add(t);
					}
					
					// Create vertices
					tc = fixedcolor ? c : DetermineThingColor(t);
					if(CreateThingBoxVerts(t, ref verts, thingsByPosition, buffercount * 6, tc)) 
					{
						buffercount++;

						//mxd
						if(!thingsByType.ContainsKey(t.Type)) thingsByType.Add(t.Type, new List<Thing>());
						thingsByType[t.Type].Add(t);
					}
					
					totalcount++;
					
					// Buffer filled?
					if(buffercount == locksize)
					{
						// Write to buffer
						stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
						stream.WriteRange(verts, 0, buffercount * 6);
						thingsvertices.Unlock();
						stream.Dispose();
						
						// Draw!
						graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);
						buffercount = 0;
						
						// Determine next lock size
						locksize = ((things.Count - totalcount) > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : (things.Count - totalcount);
					}
				}

				// Write to buffer
				stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
				if(buffercount > 0) stream.WriteRange(verts, 0, buffercount * 6);
				thingsvertices.Unlock();
				stream.Dispose();
				
				// Draw what's still remaining
				if(buffercount > 0)
					graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);

				// Done
				graphics.Shaders.Things2D.EndPass();

				//mxd. Render sprites
				int selectionColor = General.Colors.Selection.ToInt();
				graphics.Shaders.Things2D.BeginPass(1);
				float spriteShrink = General.Settings.SquareThings ? THING_SPRITE_SHRINK : THING_SPRITE_SHRINK * 2;

				foreach(KeyValuePair<int, List<Thing>> group in thingsByType)
				{
					// Find thing information
					ThingTypeInfo info = General.Map.Data.GetThingInfo(group.Key);

					// Find sprite texture
					if(info.Sprite.Length == 0) continue;

					ImageData sprite = General.Map.Data.GetSpriteImage(info.Sprite);
					if (sprite == null) continue; 
					if (!sprite.IsImageLoaded) 
					{
						sprite.SetUsedInMap(true);
						continue;
					}
					if(sprite.Texture == null) sprite.CreateTexture();

					graphics.Device.SetTexture(0, sprite.Texture);
					graphics.Shaders.Things2D.Texture1 = sprite.Texture;

					// Determine next lock size
					locksize = (group.Value.Count > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : group.Value.Count;
					verts = new FlatVertex[THING_BUFFER_SIZE * 6];

					// Go for all things
					buffercount = 0;
					totalcount = 0;

					float spriteWidth, spriteHeight;
					float spriteScale = (group.Value[0].FixedSize && (scale > 1.0f)) ? 1.0f : scale;

					if(sprite.Width > sprite.Height) 
					{
						spriteWidth = info.Radius * spriteScale - spriteShrink * spriteScale;
						spriteHeight = spriteWidth * ((float)sprite.Height / sprite.Width);
						if(spriteWidth < MINIMUM_SPRITE_RADIUS) continue; //don't render tiny little sprites
					} 
					else if(sprite.Width < sprite.Height) 
					{
						spriteHeight = info.Radius * spriteScale - spriteShrink * spriteScale;
						spriteWidth = spriteHeight * ((float)sprite.Width / sprite.Height);
						if(spriteHeight < MINIMUM_SPRITE_RADIUS) continue; //don't render tiny little sprites
					} 
					else 
					{
						spriteWidth = info.Radius * spriteScale - spriteShrink * spriteScale;
						spriteHeight = spriteWidth;
						if(spriteWidth < MINIMUM_SPRITE_RADIUS) continue; //don't render tiny little sprites
					}

					foreach(Thing t in group.Value) 
					{
						if(t.IsModel && (General.Settings.GZDrawModelsMode == ModelRenderMode.ALL || (General.Settings.GZDrawModelsMode == ModelRenderMode.SELECTION && t.Selected))) continue;
						CreateThingSpriteVerts(thingsByPosition[t], spriteWidth, spriteHeight, ref verts, buffercount * 6, t.Selected ? selectionColor : 0xFFFFFF);
						buffercount++;
						totalcount++;

						// Buffer filled?
						if(buffercount == locksize) 
						{
							// Write to buffer
							stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
							stream.WriteRange(verts, 0, buffercount * 6);
							thingsvertices.Unlock();
							stream.Dispose();

							// Draw!
							graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);

							buffercount = 0;

							// Determine next lock size
							locksize = ((group.Value.Count - totalcount) > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : (group.Value.Count - totalcount);
						}
					}

					// Write to buffer
					stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
					if(buffercount > 0) stream.WriteRange(verts, 0, buffercount * 6);
					thingsvertices.Unlock();
					stream.Dispose();

					// Draw what's still remaining
					if(buffercount > 0) 
						graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);
				}

				// Done
				graphics.Shaders.Things2D.EndPass();

				//mxd. Render thing arrows
				graphics.Device.SetTexture(0, thingtexture[thingtextureindex].Texture);
				graphics.Shaders.Things2D.Texture1 = thingtexture[thingtextureindex].Texture;
				graphics.Shaders.Things2D.BeginPass(0);

				// Determine next lock size
				locksize = (thingsByPosition.Count > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : thingsByPosition.Count;
				verts = new FlatVertex[THING_BUFFER_SIZE * 6];

				// Go for all things
				buffercount = 0;
				totalcount = 0;

				foreach (KeyValuePair<Thing, Vector2D> group in thingsByPosition) 
				{
					if(!group.Key.IsDirectional) continue;

					CreateThingArrowVerts(group.Key, ref verts, group.Value, buffercount * 6);
					buffercount++;
					totalcount++;

					// Buffer filled?
					if(buffercount == locksize) 
					{
						// Write to buffer
						stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
						stream.WriteRange(verts, 0, buffercount * 6);
						thingsvertices.Unlock();
						stream.Dispose();

						// Draw!
						graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);
						buffercount = 0;

						// Determine next lock size
						locksize = ((thingsByPosition.Count - totalcount) > THING_BUFFER_SIZE) ? THING_BUFFER_SIZE : (thingsByPosition.Count - totalcount);
					}
				}

				// Write to buffer
				stream = thingsvertices.Lock(0, locksize * 6 * FlatVertex.Stride, LockFlags.Discard);
				if(buffercount > 0) stream.WriteRange(verts, 0, buffercount * 6);
				thingsvertices.Unlock();
				stream.Dispose();

				// Draw what's still remaining
				if(buffercount > 0) 
					graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, buffercount * 2);

				//Done with this pass
				graphics.Shaders.Things2D.EndPass();

				//mxd. Render models
				if (General.Settings.GZDrawModelsMode != ModelRenderMode.NONE) 
				{
					// Set renderstates for rendering
					graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
					graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
					graphics.Device.SetRenderState(RenderState.FillMode, FillMode.Wireframe);

					graphics.Shaders.Things2D.BeginPass(2);

					Color4 cHighlight = General.Colors.Highlight.ToColorValue();
					Color4 cWire = General.Colors.ModelWireframe.ToColorValue();
					Matrix viewscale = Matrix.Scaling(scale, -scale, 0.0f);
					ModelData mde;

					foreach(KeyValuePair<int, List<Thing>> group in modelsByType) 
					{
						mde = General.Map.Data.ModeldefEntries[group.Key];
						float maxX = Math.Max(Math.Abs(mde.Model.BoundingBox[4].X), Math.Abs(mde.Model.BoundingBox[1].X));
						float maxY = Math.Max(Math.Abs(mde.Model.BoundingBox[4].Y), Math.Abs(mde.Model.BoundingBox[1].Y));
						float maxSize = Math.Max(maxX, maxY);

						foreach(Thing t in group.Value) 
						{
							if(General.Settings.GZDrawModelsMode == ModelRenderMode.SELECTION && !t.Selected) continue;
							Vector2D screenpos = ((Vector2D)t.Position).GetTransformed(translatex, translatey, scale, -scale);
							float modelScale = scale * t.ActorScale.Width * t.ScaleX;

							//should we render this model?
							if(((screenpos.x + maxSize * modelScale) <= 0.0f) || ((screenpos.x - maxSize * modelScale) >= windowsize.Width) ||
							((screenpos.y + maxSize * modelScale) <= 0.0f) || ((screenpos.y - maxSize * modelScale) >= windowsize.Height))
								continue;

							graphics.Shaders.Things2D.FillColor = t.Selected ? cHighlight : cWire;

							for(int i = 0; i < mde.Model.Meshes.Count; i++) 
							{
								float sx = t.ScaleX * t.ActorScale.Width;
								float sy = t.ScaleY * t.ActorScale.Height;
								
								Matrix modelscale = Matrix.Scaling(sx, sx, sy);
								Matrix rotation = Matrix.RotationY(-t.RollRad) * Matrix.RotationX(-t.PitchRad) * Matrix.RotationZ(t.Angle);
								Matrix position = Matrix.Translation(screenpos.x, screenpos.y, 0.0f);
								Matrix world = General.Map.Data.ModeldefEntries[t.Type].Transform * rotation * modelscale * viewscale * position;

								graphics.Shaders.Things2D.SetTransformSettings(world);
								graphics.Shaders.Things2D.ApplySettings();

								// Draw
								mde.Model.Meshes[i].DrawSubset(0);
							}
						}
					}

					//Done with this pass
					graphics.Shaders.Things2D.EndPass();
					graphics.Device.SetRenderState(RenderState.FillMode, FillMode.Solid);
				}

				graphics.Shaders.Things2D.End();
			}
		}
		
		// This adds a thing in the things buffer for rendering
		public void RenderThing(Thing t, PixelColor c, float alpha)
		{
			List<Thing> things = new List<Thing>(1);
			things.Add(t);
			RenderThingsBatch(things, alpha, true, c);
		}
		
		// This adds a thing in the things buffer for rendering
		public void RenderThingSet(ICollection<Thing> things, float alpha)
		{
			RenderThingsBatch(things, alpha, false, new PixelColor());
		}
		
		#endregion

		#region ================== Surface

		// This redraws the surface
		public void RedrawSurface()
		{
			if(renderlayer != RenderLayers.None) return; //mxd
			renderlayer = RenderLayers.Surface;

			// Rendertargets available?
			if(surfacetex != null)
			{
				// Set the rendertarget to the surface texture
				targetsurface = surfacetex.GetSurfaceLevel(0);
				if(graphics.StartRendering(true, General.Colors.Background.WithAlpha(0).ToColorValue(), targetsurface, null))
				{
					// Make sure anything we need is loaded
					General.Map.Data.UnknownTexture3D.CreateTexture();
					General.Map.Data.MissingTexture3D.CreateTexture(); //mxd

					// Set transformations
					UpdateTransformations();

					// Set states
					graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
					graphics.Device.SetRenderState(RenderState.ZEnable, false);
					graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
					graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
					graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
					graphics.Device.SetRenderState(RenderState.FogEnable, false);
					SetWorldTransformation(true);
					graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);
					
					// Prepare for rendering
					switch(viewmode)
					{
						case ViewMode.Brightness:
							surfaces.RenderSectorBrightness(yviewport);
							surfaces.RenderSectorSurfaces(graphics);
							break;
							
						case ViewMode.FloorTextures:
							surfaces.RenderSectorFloors(yviewport);
							surfaces.RenderSectorSurfaces(graphics);
							break;
							
						case ViewMode.CeilingTextures:
							surfaces.RenderSectorCeilings(yviewport);
							surfaces.RenderSectorSurfaces(graphics);
							break;
					}
				}
			}
			
			// Done
			Finish();
		}

		#endregion

		#region ================== Overlay

		// This renders geometry
		// The geometry must be a triangle list
		public void RenderGeometry(FlatVertex[] vertices, ImageData texture, bool transformcoords)
		{
			if(vertices.Length > 0)
			{
				Texture t;
				
				if(texture != null)
				{
					// Make sure the texture is loaded
					if(!texture.IsImageLoaded) texture.LoadImage();
					if(texture.Texture == null) texture.CreateTexture();
					t = texture.Texture;
				}
				else
				{
					t = General.Map.Data.WhiteTexture.Texture;
				}

				// Set renderstates for rendering
				graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
				graphics.Device.SetRenderState(RenderState.ZEnable, false);
				graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
				graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
				graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
				graphics.Device.SetRenderState(RenderState.FogEnable, false);
				graphics.Shaders.Display2D.Texture1 = t;
				graphics.Device.SetTexture(0, t);
				SetWorldTransformation(transformcoords);
				graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);
				
				// Draw
				graphics.Shaders.Display2D.Begin();
				graphics.Shaders.Display2D.BeginPass(1);
				graphics.Device.DrawUserPrimitives(PrimitiveType.TriangleList, 0, vertices.Length / 3, vertices);
				graphics.Shaders.Display2D.EndPass();
				graphics.Shaders.Display2D.End();
			}
		}

		//mxd
		public void RenderHighlight(FlatVertex[] vertices, int color) 
		{
			if(vertices.Length < 3) return;

			// Set renderstates for rendering
			graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
			graphics.Device.SetRenderState(RenderState.ZEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
			graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
			graphics.Device.SetRenderState(RenderState.FogEnable, false);

			SetWorldTransformation(true);
			graphics.Shaders.Things2D.FillColor = new Color4(color);
			graphics.Shaders.Things2D.SetSettings(1.0f);

			// Draw
			graphics.Shaders.Things2D.Begin();
			graphics.Shaders.Things2D.BeginPass(2);
			graphics.Device.DrawUserPrimitives(PrimitiveType.TriangleList, 0, vertices.Length / 3, vertices);
			graphics.Shaders.Things2D.EndPass();
			graphics.Shaders.Things2D.End();
		}

		// This renders text
		public void RenderText(TextLabel text)
		{
			// Update the text if needed
			text.Update(translatex, translatey, scale, -scale);
			
			// Text is created?
			if(text.VertexBuffer != null)
			{
				// Set renderstates for rendering
				graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
				graphics.Device.SetRenderState(RenderState.ZEnable, false);
				graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, true);
				graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
				graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
				graphics.Device.SetRenderState(RenderState.FogEnable, false);
				graphics.Shaders.Display2D.Texture1 = graphics.FontTexture;
				SetWorldTransformation(false);
				graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, true);
				graphics.Device.SetTexture(0, graphics.FontTexture);
				graphics.Device.SetStreamSource(0, text.VertexBuffer, 0, FlatVertex.Stride);

				// Draw
				graphics.Shaders.Display2D.Begin();
				graphics.Shaders.Display2D.BeginPass(1); //mxd
				//graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, text.NumFaces >> 1); //mxd. Seems to be working fine without this line, soooo...
				graphics.Device.DrawPrimitives(PrimitiveType.TriangleList, 0, text.NumFaces);
				graphics.Shaders.Display2D.EndPass();
				graphics.Shaders.Display2D.End();
			}
		}
		
		// This renders a rectangle with given border size and color
		public void RenderRectangle(RectangleF rect, float bordersize, PixelColor c, bool transformrect)
		{
			FlatQuad[] quads = new FlatQuad[4];
			
			/*
			 * Rectangle setup:
			 * 
			 *  --------------------------
			 *  |___________0____________|
			 *  |  |                  |  |
			 *  |  |                  |  |
			 *  |  |                  |  |
			 *  | 2|                  |3 |
			 *  |  |                  |  |
			 *  |  |                  |  |
			 *  |__|__________________|__|
			 *  |           1            |
			 *  --------------------------
			 * 
			 * Don't you just love ASCII art?
			 */
			
			// Calculate positions
			Vector2D lt = new Vector2D(rect.Left, rect.Top);
			Vector2D rb = new Vector2D(rect.Right, rect.Bottom);
			if(transformrect)
			{
				lt = lt.GetTransformed(translatex, translatey, scale, -scale);
				rb = rb.GetTransformed(translatex, translatey, scale, -scale);
			}
			
			// Make quads
			quads[0] = new FlatQuad(PrimitiveType.TriangleStrip, lt.x, lt.y, rb.x, lt.y - bordersize);
			quads[1] = new FlatQuad(PrimitiveType.TriangleStrip, lt.x, rb.y + bordersize, rb.x, rb.y);
			quads[2] = new FlatQuad(PrimitiveType.TriangleStrip, lt.x, lt.y - bordersize, lt.x + bordersize, rb.y + bordersize);
			quads[3] = new FlatQuad(PrimitiveType.TriangleStrip, rb.x - bordersize, lt.y - bordersize, rb.x, rb.y + bordersize);
			quads[0].SetColors(c.ToInt());
			quads[1].SetColors(c.ToInt());
			quads[2].SetColors(c.ToInt());
			quads[3].SetColors(c.ToInt());
			
			// Set renderstates for rendering
			graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
			graphics.Device.SetRenderState(RenderState.ZEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
			graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
			graphics.Device.SetRenderState(RenderState.FogEnable, false);
			SetWorldTransformation(false);
			graphics.Device.SetTexture(0, General.Map.Data.WhiteTexture.Texture);
			graphics.Shaders.Display2D.Texture1 = General.Map.Data.WhiteTexture.Texture;
			graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);
			
			// Draw
			graphics.Shaders.Display2D.Begin();
			graphics.Shaders.Display2D.BeginPass(1);
			quads[0].Render(graphics);
			quads[1].Render(graphics);
			quads[2].Render(graphics);
			quads[3].Render(graphics);
			graphics.Shaders.Display2D.EndPass();
			graphics.Shaders.Display2D.End();
		}

		// This renders a filled rectangle with given color
		public void RenderRectangleFilled(RectangleF rect, PixelColor c, bool transformrect)
		{
			// Calculate positions
			Vector2D lt = new Vector2D(rect.Left, rect.Top);
			Vector2D rb = new Vector2D(rect.Right, rect.Bottom);
			if(transformrect)
			{
				lt = lt.GetTransformed(translatex, translatey, scale, -scale);
				rb = rb.GetTransformed(translatex, translatey, scale, -scale);
			}

			// Make quad
			FlatQuad quad = new FlatQuad(PrimitiveType.TriangleStrip, lt.x, lt.y, rb.x, rb.y);
			quad.SetColors(c.ToInt());
			
			// Set renderstates for rendering
			graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
			graphics.Device.SetRenderState(RenderState.ZEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
			graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
			graphics.Device.SetRenderState(RenderState.FogEnable, false);
			SetWorldTransformation(false);
			graphics.Device.SetTexture(0, General.Map.Data.WhiteTexture.Texture);
			graphics.Shaders.Display2D.Texture1 = General.Map.Data.WhiteTexture.Texture;
			graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);

			// Draw
			graphics.Shaders.Display2D.Begin();
			graphics.Shaders.Display2D.BeginPass(1);
			quad.Render(graphics);
			graphics.Shaders.Display2D.EndPass();
			graphics.Shaders.Display2D.End();
		}

		// This renders a filled rectangle with given color
		public void RenderRectangleFilled(RectangleF rect, PixelColor c, bool transformrect, ImageData texture)
		{
			// Calculate positions
			Vector2D lt = new Vector2D(rect.Left, rect.Top);
			Vector2D rb = new Vector2D(rect.Right, rect.Bottom);
			if(transformrect)
			{
				lt = lt.GetTransformed(translatex, translatey, scale, -scale);
				rb = rb.GetTransformed(translatex, translatey, scale, -scale);
			}

			// Make quad
			FlatQuad quad = new FlatQuad(PrimitiveType.TriangleStrip, lt.x, lt.y, rb.x, rb.y);
			quad.SetColors(c.ToInt());

			// Set renderstates for rendering
			graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
			graphics.Device.SetRenderState(RenderState.ZEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
			graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
			graphics.Device.SetRenderState(RenderState.FogEnable, false);
			SetWorldTransformation(false);
			graphics.Device.SetTexture(0, texture.Texture);
			graphics.Shaders.Display2D.Texture1 = texture.Texture;
			graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);

			// Draw
			graphics.Shaders.Display2D.Begin();
			graphics.Shaders.Display2D.BeginPass(1);
			quad.Render(graphics);
			graphics.Shaders.Display2D.EndPass();
			graphics.Shaders.Display2D.End();
		}

		//mxd
		public void RenderArrow(Line3D line, PixelColor c) 
		{
			float scaler = 20f / scale;

			RenderLine(line.v1, line.v2, 0.8f, c, true);
			float angle = line.GetAngle();
			//arrowhead
			RenderLine(line.v2, new Vector2D(line.v2.x - scaler * (float)Math.Sin(angle - 0.46f), line.v2.y + scaler * (float)Math.Cos(angle - 0.46f)), 0.8f, c, true);
			RenderLine(line.v2, new Vector2D(line.v2.x - scaler * (float)Math.Sin(angle + 0.46f), line.v2.y + scaler * (float)Math.Cos(angle + 0.46f)), 0.8f, c, true);
		}

		//mxd
		public void PlotArrow(Line3D line, PixelColor c) 
		{
			float scaler = 16f / scale;

			PlotLine(line.v1, line.v2, c);
			float angle = line.GetAngle();
			//arrowhead
			PlotLine(line.v2, new Vector2D(line.v2.x - scaler * (float)Math.Sin(angle - 0.46f), line.v2.y + scaler * (float)Math.Cos(angle - 0.46f)), c);
			PlotLine(line.v2, new Vector2D(line.v2.x - scaler * (float)Math.Sin(angle + 0.46f), line.v2.y + scaler * (float)Math.Cos(angle + 0.46f)), c);
		}

		// This renders a line with given color
		public void RenderLine(Vector2D start, Vector2D end, float thickness, PixelColor c, bool transformcoords)
		{
			FlatVertex[] verts = new FlatVertex[4];
			
			// Calculate positions
			if(transformcoords)
			{
				start = start.GetTransformed(translatex, translatey, scale, -scale);
				end = end.GetTransformed(translatex, translatey, scale, -scale);
			}

			// Calculate offsets
			Vector2D delta = end - start;
			Vector2D dn = delta.GetNormal() * thickness;
			
			// Make vertices
			verts[0].x = start.x - dn.x + dn.y;
			verts[0].y = start.y - dn.y - dn.x;
			verts[0].z = 0.0f;
			verts[0].c = c.ToInt();
			verts[1].x = start.x - dn.x - dn.y;
			verts[1].y = start.y - dn.y + dn.x;
			verts[1].z = 0.0f;
			verts[1].c = c.ToInt();
			verts[2].x = end.x + dn.x + dn.y;
			verts[2].y = end.y + dn.y - dn.x;
			verts[2].z = 0.0f;
			verts[2].c = c.ToInt();
			verts[3].x = end.x + dn.x - dn.y;
			verts[3].y = end.y + dn.y + dn.x;
			verts[3].z = 0.0f;
			verts[3].c = c.ToInt();
			
			// Set renderstates for rendering
			graphics.Device.SetRenderState(RenderState.CullMode, Cull.None);
			graphics.Device.SetRenderState(RenderState.ZEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaBlendEnable, false);
			graphics.Device.SetRenderState(RenderState.AlphaTestEnable, false);
			graphics.Device.SetRenderState(RenderState.TextureFactor, -1);
			graphics.Device.SetRenderState(RenderState.FogEnable, false);
			SetWorldTransformation(false);
			graphics.Device.SetTexture(0, General.Map.Data.WhiteTexture.Texture);
			graphics.Shaders.Display2D.Texture1 = General.Map.Data.WhiteTexture.Texture;
			graphics.Shaders.Display2D.SetSettings(1f, 1f, 0f, 1f, General.Settings.ClassicBilinear);

			// Draw
			graphics.Shaders.Display2D.Begin();
			graphics.Shaders.Display2D.BeginPass(0);
			graphics.Device.DrawUserPrimitives<FlatVertex>(PrimitiveType.TriangleStrip, 0, 2, verts);
			graphics.Shaders.Display2D.EndPass();
			graphics.Shaders.Display2D.End();
		}

		#endregion

		#region ================== Geometry

		// This renders the linedefs of a sector with special color
		public void PlotSector(Sector s, PixelColor c)
		{
			// Go for all sides in the sector
			foreach(Sidedef sd in s.Sidedefs)
			{
				// Render this linedef
				PlotLinedef(sd.Line, c);

				// Render the two vertices on top
				PlotVertex(sd.Line.Start, DetermineVertexColor(sd.Line.Start));
				PlotVertex(sd.Line.End, DetermineVertexColor(sd.Line.End));
			}
		}

		// This renders the linedefs of a sector
		public void PlotSector(Sector s)
		{
			// Go for all sides in the sector
			foreach(Sidedef sd in s.Sidedefs)
			{
				// Render this linedef
				PlotLinedef(sd.Line, DetermineLinedefColor(sd.Line));

				// Render the two vertices on top
				PlotVertex(sd.Line.Start, DetermineVertexColor(sd.Line.Start));
				PlotVertex(sd.Line.End, DetermineVertexColor(sd.Line.End));
			}
		}	

		// This renders a simple line
		public void PlotLine(Vector2D start, Vector2D end, PixelColor c)
		{
			// Transform coordinates
			Vector2D v1 = start.GetTransformed(translatex, translatey, scale, -scale);
			Vector2D v2 = end.GetTransformed(translatex, translatey, scale, -scale);

			// Draw line
			plotter.DrawLineSolid((int)v1.x, (int)v1.y, (int)v2.x, (int)v2.y, ref c);
		}
		
		// This renders a single linedef
		public void PlotLinedef(Linedef l, PixelColor c)
		{
			// Transform vertex coordinates
			Vector2D v1 = l.Start.Position.GetTransformed(translatex, translatey, scale, -scale);
			Vector2D v2 = l.End.Position.GetTransformed(translatex, translatey, scale, -scale);

			// Draw line. mxd: added 3d-floor indication
			if(l.ExtraFloorFlag && General.Settings.GZMarkExtraFloors)
				plotter.DrawLine3DFloor(v1, v2, ref c, General.Colors.ThreeDFloor);
			else
				plotter.DrawLineSolid((int)v1.x, (int)v1.y, (int)v2.x, (int)v2.y, ref c);

			// Calculate normal indicator
			float mx = (v2.x - v1.x) * 0.5f;
			float my = (v2.y - v1.y) * 0.5f;

			// Draw normal indicator
			plotter.DrawLineSolid((int)(v1.x + mx), (int)(v1.y + my),
								  (int)((v1.x + mx) - (my * l.LengthInv) * linenormalsize),
								  (int)((v1.y + my) + (mx * l.LengthInv) * linenormalsize), ref c);
		}
		
		// This renders a set of linedefs
		public void PlotLinedefSet(ICollection<Linedef> linedefs)
		{
			// Go for all linedefs
			foreach(Linedef l in linedefs) PlotLinedef(l, DetermineLinedefColor(l));
		}

		// This renders a single vertex
		public void PlotVertex(Vertex v, int colorindex)
		{
			// Transform vertex coordinates
			Vector2D nv = v.Position.GetTransformed(translatex, translatey, scale, -scale);

			// Draw pixel here
			plotter.DrawVertexSolid((int)nv.x, (int)nv.y, vertexsize, ref General.Colors.Colors[colorindex], ref General.Colors.BrightColors[colorindex], ref General.Colors.DarkColors[colorindex]);
		}

		// This renders a single vertex at specified coordinates
		public void PlotVertexAt(Vector2D v, int colorindex)
		{
			// Transform vertex coordinates
			Vector2D nv = v.GetTransformed(translatex, translatey, scale, -scale);

			// Draw pixel here
			plotter.DrawVertexSolid((int)nv.x, (int)nv.y, vertexsize, ref General.Colors.Colors[colorindex], ref General.Colors.BrightColors[colorindex], ref General.Colors.DarkColors[colorindex]);
		}
		
		// This renders a set of vertices
		public void PlotVerticesSet(ICollection<Vertex> vertices)
		{
			// Go for all vertices
			foreach(Vertex v in vertices) PlotVertex(v, DetermineVertexColor(v));
		}

		#endregion
	}
}