Multi barrel offset

Source/CombatExtended/CombatExtended/Defs/MultiBarrelExtension.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using UnityEngine;
+using Verse;
+
+namespace CombatExtended
+{
+    public class MultiBarrelExtension : DefModExtension
+    {
+        public List<Vector2> offsets = new List<Vector2>();
+
+        public Vector2 GetOffsetFor(int index)
+        {
+            if (offsets.NullOrEmpty())
+            {
+                return Vector2.zero;
+            }
+            int i = index % offsets.Count;
+            return offsets[i];
+        }
+    }
+}

Source/CombatExtended/CombatExtended/Verbs/Verb_LaunchProjectileCE.cs

@@ -38,6 +38,8 @@ public class Verb_LaunchProjectileCE : Verb
         public CompFireModes compFireModes = null;
         public CompChangeableProjectile compChangeable = null;
         public CompApparelReloadable compReloadable = null;
+        protected int multiBarrelIndex;
+
         private float shotSpeed = -1;
 
         private float rotationDegrees = 0f;
@@ -63,6 +65,7 @@ public class Verb_LaunchProjectileCE : Verb
 
         public VerbPropertiesCE VerbPropsCE => verbProps as VerbPropertiesCE;
         public ProjectilePropertiesCE projectilePropsCE => Projectile.projectile as ProjectilePropertiesCE;
+        public MultiBarrelExtension multiBarrelExt => EquipmentSource.def.GetModExtension<MultiBarrelExtension>();
 
         // Returns either the pawn aiming the weapon or in case of turret guns the turret operator or null if neither exists        
         public Pawn ShooterPawn => CasterPawn ?? CE_Utility.TryGetTurretOperator(caster);
@@ -542,6 +545,16 @@ public virtual void ShiftTarget(ShiftVecReport report, bool calculateMechanicalO
             shotRotation = (lastShotRotation + rotationDegrees + spreadVec.x) % 360;
             shotAngle = angleRadians + spreadVec.y * Mathf.Deg2Rad;
             distance = (newTargetLoc - sourceLoc).magnitude;
+            sourceLoc += IncrementBarrelCount();
+        }
+
+        /// <summary>
+        /// Add 1 to multi barrel index then returns the barrel offset.
+        /// </summary>
+        protected Vector2 IncrementBarrelCount()
+        {
+            multiBarrelIndex++;
+            return multiBarrelExt?.GetOffsetFor(multiBarrelIndex).RotatedBy(shotRotation) ?? Vector2.zero;
         }
 
         /// <summary>