Scratch that. NOW they're working properly.

DepthsBelow/DepthsBelow/Camera.cs

@@ -38,9 +38,8 @@ namespace DepthsBelow
 		public Rectangle ScreenToWorld(Rectangle screenRectangle)
 		{
 			var pos = ScreenToWorld(new Vector2(screenRectangle.X, screenRectangle.Y));
-			screenRectangle.X = (int)pos.X;
-			screenRectangle.Y = (int)pos.Y;
-			return screenRectangle;
+			var size = ScreenToWorld(new Vector2(screenRectangle.X + screenRectangle.Width, screenRectangle.Y + screenRectangle.Height)) - pos;
+			return new Rectangle((int)pos.X, (int)pos.Y, (int)size.X, (int)size.Y);
 		}
 
 		public Vector2 WorldToScreen(Vector2 worldPos)
@@ -48,12 +47,11 @@ namespace DepthsBelow
 			return Vector2.Transform(worldPos, Transform);
 		}
 
-		public Rectangle WorldToScreen(Rectangle screenRectangle)
+		public Rectangle WorldToScreen(Rectangle worldRectangle)
 		{
-			var pos = WorldToScreen(new Vector2(screenRectangle.X, screenRectangle.Y));
-			screenRectangle.X = (int)pos.X;
-			screenRectangle.Y = (int)pos.Y;
-			return screenRectangle;
+			var pos = WorldToScreen(new Vector2(worldRectangle.X, worldRectangle.Y));
+			var size = WorldToScreen(new Vector2(worldRectangle.X + worldRectangle.Width, worldRectangle.Y + worldRectangle.Height)) - pos;
+			return new Rectangle((int)pos.X, (int)pos.Y, (int)size.X, (int)size.Y);
 		}
 
 		public void Update(GameTime gameTime)

DepthsBelow/DepthsBelow/Core.cs

@@ -210,6 +210,15 @@ namespace DepthsBelow
 				}
 			}
 
+#if DEBUG
+			var debugTexture = new Texture2D(GraphicsDevice, 1, 1);
+			debugTexture.SetData(new Color[] { Color.White });
+			foreach (var collisionComponent in EntityManager.GetComponents<Component.Collision>())
+			{
+				spriteBatch.Draw(debugTexture, collisionComponent.Rectangle, Color.Red * 0.5f);
+			}
+#endif
+
 			// Draw mouse input visuals
 			MouseInput.Draw(spriteBatch);
 

DepthsBelow/DepthsBelow/GUI/Frame.cs

@@ -383,7 +383,15 @@ namespace DepthsBelow.GUI
 			if (Visible)
 			{
 				if (Texture != null)
-					spriteBatch.Draw(Texture, AbsoluteRectangle, Color);
+					spriteBatch.Draw(Texture, 
+						AbsoluteRectangle, 
+						null, 
+						Color, 
+						0, 
+						Vector2.Zero, 
+						((Width < 0) ? SpriteEffects.FlipHorizontally : 0)
+						| ((Height < 0) ? SpriteEffects.FlipVertically : 0),
+						0);
 
 				/*foreach (var child in Children)
 					child.Draw(spriteBatch);*/

DepthsBelow/DepthsBelow/Interface.cs

@@ -153,8 +153,13 @@ namespace DepthsBelow
 					var selectFrame = (GUI.Frame)frame["selectionFrame"];
 					if (selectFrame.Visible)
 					{
+						Console.WriteLine("Before: " + selectFrame.AbsoluteRectangle.X + ", " + selectFrame.AbsoluteRectangle.Y + ", " + selectFrame.AbsoluteRectangle.Width + ", " + selectFrame.AbsoluteRectangle.Height);
+
 						var intersectionRectangle = core.Camera.ScreenToWorld(selectFrame.AbsoluteRectangle);
 
+						Console.WriteLine("After: " + intersectionRectangle.X + ", " + intersectionRectangle.Y + ", " + intersectionRectangle.Width + ", " + intersectionRectangle.Height);
+
+
 						// Select all units in the rectangle
 						foreach (var soldier in core.Squad)
 						{
@@ -192,7 +197,7 @@ namespace DepthsBelow
 
 			var button = new GUI.Button(UIParent);
 			button.SetTexture("images/Enter");
-			button.X = 100;
+			button.X = 200;
 			button.Y = 100;
 			button.Width = 55;
 			button.Height = 40;

DepthsBelow/DepthsBelow/MouseInput.cs

@@ -41,8 +41,9 @@ namespace DepthsBelow
 			selectionTexture = new Texture2D(core.GraphicsDevice, 1, 1);
 			selectionTexture.SetData(new Color[] { Color.White });
 
-            gridTexture = new Texture2D(core.GraphicsDevice, 1, 1);
-            gridTexture.SetData(new Color[] { Color.White });
+            //gridTexture = new Texture2D(core.GraphicsDevice, 1, 1);
+            //gridTexture.SetData(new Color[] { Color.White });
+			gridTexture = GameServices.GetService<ContentManager>().Load<Texture2D>("images/selection");
 		}
 
 		public void OnPress(MouseState ms, GameTime gameTime)
@@ -317,7 +318,7 @@ namespace DepthsBelow
 		public void Draw(SpriteBatch spriteBatch)
 		{
 			spriteBatch.Draw(selectionTexture, selectionRectangle, Color.Red * 0.5f);
-			spriteBatch.Draw(gridTexture, gridRectangle, Color.Yellow * 0.3f);
+			spriteBatch.Draw(gridTexture, gridRectangle, Color.White * 0.7f);
 
             if (checkingDirection == true) 
             {

DepthsBelow/DepthsBelowContent/DepthsBelowContent.contentproj

@@ -224,6 +224,13 @@
       <Processor>TextureProcessor</Processor>
     </Compile>
   </ItemGroup>
+  <ItemGroup>
+    <Compile Include="images\selection.png">
+      <Name>selection</Name>
+      <Importer>TextureImporter</Importer>
+      <Processor>TextureProcessor</Processor>
+    </Compile>
+  </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Microsoft\XNA Game Studio\$(XnaFrameworkVersion)\Microsoft.Xna.GameStudio.ContentPipeline.targets" />
   <!--  To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.