Faster bitmap editing

OpenRA.Game/Graphics/Minimap.cs

@@ -70,15 +70,22 @@ namespace OpenRA.Graphics
 		public static Bitmap RenderTerrainBitmap(Map map, TileSet tileset)
 		{
 			var terrain = new Bitmap(map.MapSize.X, map.MapSize.Y);
+			var bitmapData = terrain.LockBits(new Rectangle(0, 0, terrain.Width, terrain.Height),
+				ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
+			unsafe
+			{
+				int* c = (int*)bitmapData.Scan0;
 
 				for (var x = 0; x < map.MapSize.X; x++)
 					for (var y = 0; y < map.MapSize.Y; y++)
 					{
 						var type = tileset.GetTerrainType(map.MapTiles[x, y]);
-					terrain.SetPixel(x, y, map.IsInMap(x, y)
+						*(c + (y * bitmapData.Stride >> 2) + x) = map.IsInMap(x, y)
-						? Color.FromArgb(alpha, tileset.Terrain[type].Color)
+							? Color.FromArgb(alpha, tileset.Terrain[type].Color).ToArgb()
-						: shroudColor);
+							: shroudColor.ToArgb();
 					}
+			}
+			terrain.UnlockBits(bitmapData);
 			return terrain;
 		}
 
@@ -182,6 +189,13 @@ namespace OpenRA.Graphics
 			var size = NextPowerOf2(Math.Max(map.Width, map.Height));
 			Bitmap terrain = new Bitmap(size, size);
 			
+			var bitmapData = terrain.LockBits(new Rectangle(0, 0, terrain.Width, terrain.Height),
+				ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
+
+			unsafe
+			{
+				int* c = (int*)bitmapData.Scan0;
+
 				for (var x = 0; x < map.Width; x++)
 					for (var y = 0; y < map.Height; y++)
 					{
@@ -196,8 +210,11 @@ namespace OpenRA.Graphics
 						if (res != null)
 							type = res;
 						
-					terrain.SetPixel(x, y, tileset.Terrain[type].Color);
+						*(c + (y * bitmapData.Stride >> 2) + x) = tileset.Terrain[type].Color.ToArgb();
 					}
+			}
+			terrain.UnlockBits(bitmapData);
+
 			return terrain;
 		}
 	}