Replace FlashPaletteEffect with a post-processing shader.

OpenRA.Mods.Common/Traits/PaletteEffects/FlashPostProcessEffect.cs

@@ -0,0 +1,67 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using OpenRA.Graphics;
+using OpenRA.Primitives;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Traits
+{
+	[TraitLocation(SystemActors.World | SystemActors.EditorWorld)]
+	[Desc("Used for bursted one-colored whole screen effects. Add this to the world actor.")]
+	public class FlashPostProcessEffectInfo : TraitInfo
+	{
+		[Desc("Measured in ticks.")]
+		public readonly int Length = 20;
+
+		public readonly Color Color = Color.White;
+
+		[Desc("Set this when using multiple independent flash effects.")]
+		public readonly string Type = null;
+
+		public override object Create(ActorInitializer init) { return new FlashPostProcessEffect(this); }
+	}
+
+	public class FlashPostProcessEffect : RenderPostProcessPassBase, ITick
+	{
+		public readonly FlashPostProcessEffectInfo Info;
+		int remainingFrames;
+		float blend;
+
+		public FlashPostProcessEffect(FlashPostProcessEffectInfo info)
+			: base("flash", PostProcessPassType.AfterWorld)
+		{
+			Info = info;
+		}
+
+		public void Enable(int ticks)
+		{
+			if (ticks == -1)
+				remainingFrames = Info.Length;
+			else
+				remainingFrames = ticks;
+		}
+
+		void ITick.Tick(Actor self)
+		{
+			if (remainingFrames > 0)
+				blend = Math.Min((float)--remainingFrames / Info.Length, 1);
+		}
+
+		protected override bool Enabled => remainingFrames > 0;
+		protected override void PrepareRender(WorldRenderer wr, IShader shader)
+		{
+			shader.SetVec("Blend", blend);
+			shader.SetVec("Color", (float)Info.Color.B / 255, (float)Info.Color.G / 255, (float)Info.Color.R / 255);
+		}
+	}
+}