Fade in the menu palette effect over a few frames

OpenRA.Mods.Cnc/CncMenuPaletteEffect.cs

@@ -0,0 +1,85 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made 
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System.Collections.Generic;
+using System.Drawing;
+using OpenRA.FileFormats;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Cnc
+{
+	class CncMenuPaletteEffectInfo : TraitInfo<CncMenuPaletteEffect> { }
+
+	public class CncMenuPaletteEffect : IPaletteModifier, ITick
+	{		
+		public enum EffectType { None, Black, Desaturated }
+
+		const int effectLength = 10;
+		int remainingFrames;
+		
+		EffectType from = EffectType.Black;
+		EffectType to = EffectType.Black;
+		
+		public void Fade(EffectType type)
+		{
+			remainingFrames = effectLength;
+			from = to;
+			to = type;
+		}
+
+		public void Tick(Actor self)
+		{
+			if (remainingFrames > 0)
+				remainingFrames--;
+		}
+		
+		Color ColorForEffect(EffectType t, Color orig)
+		{
+			switch(t)
+			{
+				case EffectType.Black:
+					return Color.FromArgb(orig.A, Color.Black);
+				case EffectType.Desaturated:
+					var lum = (int)(255 * orig.GetBrightness());
+					return Color.FromArgb(orig.A, lum, lum, lum);
+				default:
+				case EffectType.None:
+					return orig;
+			}
+		}
+		
+		public void AdjustPalette(Dictionary<string,Palette> palettes)
+		{
+			if (to == EffectType.None && remainingFrames == 0)
+				return;
+			
+			var excludePalettes = new List<string>(){"cursor", "chrome", "colorpicker", "shroud", "fog"};
+			foreach (var pal in palettes)
+			{
+				if (excludePalettes.Contains(pal.Key))
+					continue;
+				
+				for (var x = 0; x < 256; x++)
+				{
+					var orig = pal.Value.GetColor(x);
+					var t = ColorForEffect(to, orig);
+					
+					if (remainingFrames == 0)
+						pal.Value.SetColor(x, t);
+					else
+					{
+						var f = ColorForEffect(from, orig);
+						pal.Value.SetColor(x, OpenRA.Graphics.Util.Lerp((float)remainingFrames / effectLength, t, f));
+					}
+				}
+			}
+		}
+	}
+}