add a simple projectile with random sequences for debris effects

OpenRA.Mods.Common/Effects/Shrapnel.cs

@@ -0,0 +1,147 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2015 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;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using OpenRA.Effects;
+using OpenRA.GameRules;
+using OpenRA.Graphics;
+using OpenRA.Mods.Common.Graphics;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Effects
+{
+	public class ShrapnelInfo : IProjectileInfo
+	{
+		[Desc("Projectile speed in WDist / tick, two values indicate variable velocity.")]
+		public readonly WDist[] Speed = { new WDist(17) };
+
+		[Desc("Image to display.")]
+		public readonly string Image = null;
+
+		[Desc("Loop these sequences of Image while this projectile is moving.")]
+		[SequenceReference("Image")] public readonly string[] Sequences = { "idle" };
+
+		[Desc("The palette used to draw this projectile.")]
+		public readonly string Palette = "effect";
+
+		[Desc("Does this projectile have a shadow?")]
+		public readonly bool Shadow = false;
+
+		[Desc("Palette to use for this projectile's shadow if Shadow is true.")]
+		public readonly string ShadowPalette = "shadow";
+
+		[Desc("Arc in WAngles, two values indicate variable arc.")]
+		public readonly WAngle[] Angle = { WAngle.Zero };
+
+		public IEffect Create(ProjectileArgs args) { return new Shrapnel(this, args); }
+	}
+
+	public class Shrapnel : IEffect, ISync
+	{
+		readonly ShrapnelInfo info;
+		readonly ProjectileArgs args;
+		readonly Animation anim;
+		[Sync] readonly WAngle angle;
+		[Sync] readonly WDist speed;
+
+		[Sync] WPos pos, target;
+		[Sync] int length;
+		[Sync] int facing;
+		[Sync] int ticks;
+
+		[Sync] public Actor SourceActor { get { return args.SourceActor; } }
+
+		public Shrapnel(ShrapnelInfo info, ProjectileArgs args)
+		{
+			this.info = info;
+			this.args = args;
+			this.pos = args.Source;
+
+			var world = args.SourceActor.World;
+
+			if (info.Angle.Length > 1)
+				angle = new WAngle(world.SharedRandom.Next(info.Angle[0].Angle, info.Angle[1].Angle));
+			else
+				angle = info.Angle[0];
+
+			if (info.Speed.Length > 1)
+				speed = new WDist(world.SharedRandom.Next(info.Speed[0].Length, info.Speed[1].Length));
+			else
+				speed = info.Speed[0];
+
+			target = args.PassiveTarget;
+
+			facing = OpenRA.Traits.Util.GetFacing(target - pos, 0);
+			length = Math.Max((target - pos).Length / speed.Length, 1);
+
+			if (!string.IsNullOrEmpty(info.Image))
+			{
+				anim = new Animation(world, info.Image, GetEffectiveFacing);
+				anim.PlayRepeating(info.Sequences.Random(world.SharedRandom));
+			}
+		}
+
+		int GetEffectiveFacing()
+		{
+			var at = (float)ticks / (length - 1);
+			var attitude = angle.Tan() * (1 - 2 * at) / (4 * 1024);
+
+			var u = (facing % 128) / 128f;
+			var scale = 512 * u * (1 - u);
+
+			return (int)(facing < 128
+				? facing - scale * attitude
+				: facing + scale * attitude);
+		}
+
+		public void Tick(World world)
+		{
+			if (anim != null)
+				anim.Tick();
+
+			pos = WPos.LerpQuadratic(args.Source, target, angle, ticks, length);
+
+			if (ticks++ >= length)
+				Explode(world);
+		}
+
+		public IEnumerable<IRenderable> Render(WorldRenderer wr)
+		{
+			if (anim == null || ticks >= length)
+				yield break;
+
+			var world = args.SourceActor.World;
+			if (!world.FogObscures(pos))
+			{
+				if (info.Shadow)
+				{
+					var dat = world.Map.DistanceAboveTerrain(pos);
+					var shadowPos = pos - new WVec(0, 0, dat.Length);
+					foreach (var r in anim.Render(shadowPos, wr.Palette(info.ShadowPalette)))
+						yield return r;
+				}
+
+				var palette = wr.Palette(info.Palette);
+				foreach (var r in anim.Render(pos, palette))
+					yield return r;
+			}
+		}
+
+		void Explode(World world)
+		{
+			world.AddFrameEndTask(w => w.Remove(this));
+
+			args.Weapon.Impact(Target.FromPos(pos), args.SourceActor, args.DamageModifiers);
+		}
+	}
+}