shroud: it works. perf is pretty ugly, and there are a lot of small bugs.

OpenRa.FileFormats/IPaletteRemap.cs

@@ -0,0 +1,9 @@
+using System;
+using System.Drawing;
+namespace OpenRa.FileFormats
+{
+	public interface IPaletteRemap
+	{
+		Color GetRemappedColor(Color original, int index);
+	}
+}

OpenRa.FileFormats/OpenRa.FileFormats.csproj

@@ -55,6 +55,7 @@
     <Compile Include="Format80.cs" />
     <Compile Include="IniFile.cs" />
     <Compile Include="IniWriter.cs" />
+    <Compile Include="IPaletteRemap.cs" />
     <Compile Include="Map.cs" />
     <Compile Include="PackageEntry.cs" />
     <Compile Include="Package.cs" />
@@ -62,6 +63,7 @@
     <Compile Include="PaletteRemap.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ShpReader.cs" />
+    <Compile Include="ShroudPaletteRemap.cs" />
     <Compile Include="Terrain.cs" />
     <Compile Include="TileReference.cs" />
     <Compile Include="TileSet.cs" />

OpenRa.FileFormats/Palette.cs

@@ -31,7 +31,7 @@ namespace OpenRa.FileFormats
 			colors[4] = Color.FromArgb(140, 0, 0, 0);
 		}
 
-		public Palette(Palette p, PaletteRemap r)
+		public Palette(Palette p, IPaletteRemap r)
 		{
 			for (int i = 0; i < 256; i++)
 				colors.Add(r.GetRemappedColor(p.GetColor(i), i));

OpenRa.FileFormats/PaletteRemap.cs

@@ -4,7 +4,7 @@ using System.IO;
 
 namespace OpenRa.FileFormats
 {
-	public class PaletteRemap
+	public class PaletteRemap : IPaletteRemap
 	{
 		int offset;
 		List<Color> remapColors = new List<Color>();

OpenRa.FileFormats/ShroudPaletteRemap.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Drawing;
+
+namespace OpenRa.FileFormats
+{
+	public class ShroudPaletteRemap : IPaletteRemap
+	{
+		public Color GetRemappedColor(Color original, int index)
+		{
+			// false-color version for debug
+
+			//return new[] { 
+			//    Color.Orange, Color.Green, 
+			//    Color.Blue, Color.Yellow, 
+			//    Color.Black, 
+			//    Color.Red, 
+			//    Color.Purple, 
+			//    Color.Cyan}[index % 8];
+
+			return new[] { 
+			    Color.Transparent, Color.Green, 
+			    Color.Blue, Color.Yellow, 
+			    Color.Black, 
+			    Color.FromArgb(192,0,0,0), 
+			    Color.FromArgb(128,0,0,0), 
+			    Color.FromArgb(64,0,0,0)}[index % 8];
+		}
+	}
+}

OpenRa.Game/Game.cs

@@ -102,6 +102,12 @@ namespace OpenRa.Game
 
 			oreFrequency = (int)(Rules.General.GrowthRate * 60 * 1000);
 			oreTicks = oreFrequency;
+
+			foreach (var a in Game.world.Actors)
+				if (a.Info != null && a.Owner == players[0])
+					players[0].Shroud.Explore(a);
+
+			Game.world.ActorAdded += a => players[0].Shroud.Explore(a);
 		}
 
 		public static void Initialize(string mapName, Renderer renderer, int2 clientSize, 

OpenRa.Game/Graphics/HardwarePalette.cs

@@ -3,7 +3,12 @@ using OpenRa.FileFormats;
 
 namespace OpenRa.Game.Graphics
 {
-	public enum PaletteType { Gold, Blue, Red, Orange, Teal, Salmon, Green, Gray, Shadow, Invuln, Chrome };
+	public enum PaletteType
+	{
+		Gold, Blue, Red, Orange, Teal, Salmon, Green, Gray, 
+		Shadow, Invuln, Chrome, Shroud,
+	};
+
 	class HardwarePalette : Sheet
 	{
 		const int maxEntries = 16;
@@ -21,6 +26,7 @@ namespace OpenRa.Game.Graphics
 			AddPalette(new Palette(pal, new PaletteRemap(Color.FromArgb(140, 0, 0, 0))));
 			AddPalette(pal);	// iron curtain. todo: remap!
 			AddPalette(pal);	// chrome (it's like gold, but we're not going to hax it in palettemods)
+			AddPalette(new Palette(pal, new ShroudPaletteRemap()));
 		}
 
 		int AddPalette(Palette p)

OpenRa.Game/Graphics/WorldRenderer.cs

@@ -87,6 +87,8 @@ namespace OpenRa.Game.Graphics
 			if (Game.controller.orderGenerator != null)
 				Game.controller.orderGenerator.Render();
 
+			Game.LocalPlayer.Shroud.Draw(spriteRenderer);
+
 			lineRenderer.Flush();
 			spriteRenderer.Flush();
 		}

OpenRa.Game/Shroud.cs

@@ -3,15 +3,85 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using IjwFramework.Types;
+using OpenRa.Game.Graphics;
 
 namespace OpenRa.Game
 {
 	class Shroud
 	{
 		bool[,] explored = new bool[128, 128];
+		Sprite[] shadowBits = SpriteSheetBuilder.LoadAllSprites("shadow");
+		Sprite[,] sprites = new Sprite[128, 128];
+		bool dirty;
 
 		public void Explore(Actor a)
 		{
+			foreach (var t in Game.FindTilesInCircle(a.Location, a.Info.Sight))
+				explored[t.X, t.Y] = true;
+
+			dirty = true;
+		}
+
+		Sprite ChooseShroud(int i, int j)
+		{
+			// bits are for exploredness: left, right, up, down, self
+			var n = new[] {
+				0xf,0xf,0xf,0xf,	
+				0xf,0x0f,0x0f,0xf,
+				0xf,0x0f,0x0f,0xf,	
+				0xf,0xf,0xf,0xf,
+				0,7,13,0,	
+				14,6,12,4,
+				11,3,9,1,	
+				0,2,8,0,
+			};
+			
+			var v = 0;
+			if (explored[i-1,j]) v |= 1;
+			if (explored[i+1,j]) v |= 2;
+			if (explored[i,j-1]) v |= 4;
+			if (explored[i,j+1]) v |= 8;
+			if (explored[i, j]) v |= 16;
+
+			var x = n[v];
+
+			if (x == 0)
+			{
+				// bits are for exploredness: TL, TR, BR, BL
+				var m = new[] { 
+					46, 41, 42, 38,
+					43, 45, 39, 35,
+					40, 37, 44, 34,
+					36, 33, 32, 47,
+				};
+
+				var u = 0;
+				if (explored[i - 1, j - 1]) u |= 1;
+				if (explored[i + 1, j - 1]) u |= 2;
+				if (explored[i + 1, j + 1]) u |= 4;
+				if (explored[i - 1, j + 1]) u |= 8;
+				return shadowBits[m[u]];
+			}
+
+			return shadowBits[x];
+		}
+
+		public void Draw(SpriteRenderer r)
+		{
+			if (dirty)
+			{
+				dirty = false;
+				for (int j = 1; j < 127; j++)
+					for (int i = 1; i < 127; i++)
+						sprites[i, j] = ChooseShroud(i, j);
+			}
+
+			for (var j = 0; j < 128; j++)
+				for (var i = 0; i < 128; i++)
+					if (sprites[i,j] != null)
+						r.DrawSprite(sprites[i, j], 
+							Game.CellSize * new float2(i, j), 
+							PaletteType.Shroud);
 		}
 	}
 }

OpenRa.Game/Traits/Mobile.cs

@@ -18,7 +18,16 @@ namespace OpenRa.Game.Traits
 		public int2 toCell
 		{
 			get { return self.Location; }
-			set { Game.UnitInfluence.Remove(self, this); self.Location = value; Game.UnitInfluence.Add(self, this); }
+			set
+			{
+				if (self.Location != value)
+				{
+					Game.UnitInfluence.Remove(self, this);
+					self.Location = value;
+					self.Owner.Shroud.Explore(self);
+				}
+				Game.UnitInfluence.Add(self, this);
+			}
 		}
 
 		public Mobile(Actor self)

SequenceEditor/Program.cs

@@ -83,7 +83,8 @@ namespace SequenceEditor
 			Doc = new XmlDocument(); 
 			Doc.Load(XmlFilename);
 
-			Pal = new Palette(FileSystem.Open("temperat.pal"));
+			var tempPal = new Palette(FileSystem.Open("temperat.pal"));
+			Pal = new Palette(tempPal, new ShroudPaletteRemap());
 
 			UnitName = args.FirstOrDefault( x => !x.EndsWith(".xml") );
 			if (UnitName == null)