Re-organize all projects (#4166)

Content.Shared/Projectiles/ProjectileSystem.cs

@@ -0,0 +1,23 @@
+using Robust.Shared.GameObjects;
+using Robust.Shared.Physics.Dynamics;
+
+namespace Content.Shared.Projectiles
+{
+    public sealed class ProjectileSystem : EntitySystem
+    {
+        public override void Initialize()
+        {
+            base.Initialize();
+            SubscribeLocalEvent<SharedProjectileComponent, PreventCollideEvent>(PreventCollision);
+        }
+
+        private void PreventCollision(EntityUid uid, SharedProjectileComponent component, PreventCollideEvent args)
+        {
+            if (component.IgnoreShooter && args.BodyB.Owner.Uid == component.Shooter)
+            {
+                args.Cancel();
+                return;
+            }
+        }
+    }
+}

Content.Shared/Projectiles/SharedProjectileComponent.cs

@@ -0,0 +1,42 @@
+#nullable enable
+using System;
+using Content.Shared.NetIDs;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Projectiles
+{
+    public abstract class SharedProjectileComponent : Component
+    {
+        private bool _ignoreShooter = true;
+        public override string Name => "Projectile";
+        public override uint? NetID => ContentNetIDs.PROJECTILE;
+
+        public EntityUid Shooter { get; protected set; }
+
+        public bool IgnoreShooter
+        {
+            get => _ignoreShooter;
+            set
+            {
+                if (_ignoreShooter == value) return;
+
+                _ignoreShooter = value;
+                Dirty();
+            }
+        }
+
+        [NetSerializable, Serializable]
+        protected class ProjectileComponentState : ComponentState
+        {
+            public ProjectileComponentState(EntityUid shooter, bool ignoreShooter) : base(ContentNetIDs.PROJECTILE)
+            {
+                Shooter = shooter;
+                IgnoreShooter = ignoreShooter;
+            }
+
+            public EntityUid Shooter { get; }
+            public bool IgnoreShooter { get; }
+        }
+    }
+}