Commit before attempting to add concurrency to loop

src/Dodge/Projectile/Create.hs

@@ -1,7 +1,6 @@
 module Dodge.Projectile.Create where
 
 import Dodge.Data.World
-import Dodge.Item.Location
 import Geometry
 import qualified IntMapHelp as IM
 import LensHelp
@@ -30,24 +29,22 @@ fireShell it cr =
 
 makeShell :: Item -> Creature -> [ProjectileUpdate] -> World -> World
 makeShell it cr theupdate w =
-    w & cWorld . projectiles
-        %~ IM.insert
-            i
-            Shell
-                { _prjPos = pos
-                , _prjZ = 20
-                , _prjStartPos = pos
-                , _prjVel = rotateV dir (V2 1 0)
-                , _prjDraw = DrawShell
-                , _prjID = i
-                , _prjAcc = rotateV dir (V2 3 0)
-                , _prjDir = dir
-                , _prjSpin = 0
-                , _prjPayload = _amPayload $ _laAmmoType am
-                , _prjTimer = 350
-                , _prjUpdates = theupdate
-                , _prjMITID = Just $ _itID it
-                }
+    w & cWorld . projectiles . at i
+        ?~ Shell
+            { _prjPos = pos
+            , _prjZ = 20
+            , _prjStartPos = pos
+            , _prjVel = rotateV dir (V2 1 0)
+            , _prjDraw = DrawShell
+            , _prjID = i
+            , _prjAcc = rotateV dir (V2 3 0)
+            , _prjDir = dir
+            , _prjSpin = 0
+            , _prjPayload = _amPayload $ _laAmmoType am
+            , _prjTimer = 350
+            , _prjUpdates = theupdate
+            , _prjMITID = Just $ _itID it
+            }
   where
     i = IM.newKey $ _props (_cWorld w)
     dir = _crDir cr
@@ -55,20 +52,18 @@ makeShell it cr theupdate w =
     am = _heldConsumption $ _itUse it
 
 fireTrackingShell :: Item -> Creature -> World -> World
-fireTrackingShell it cr w = addTrackRocket w'
+fireTrackingShell it cr =
+    makeShell
+        it
+        cr
+        [ PJRemoteShellCollisionCheck
+        , PJDecTimMvVel
+        , PJSpin 335 (_crID cr) spinamount
+        , PJTrack (350 - thrustdelay) 0 (_itID it)
+        , PJThrust (350 - thrustdelay) 0
+        , PJReduceSpin (1 - fromIntegral spindrag * 2 / 200)
+        ]
   where
-    (w', itid) = getHeldItemLoc cr w
-    addTrackRocket =
-        makeShell
-            it
-            cr
-            [ PJRemoteShellCollisionCheck
-            , PJDecTimMvVel
-            , PJSpin 335 (_crID cr) spinamount
-            , PJTrack (350 - thrustdelay) 0 itid
-            , PJThrust (350 - thrustdelay) 0
-            , PJReduceSpin (1 - fromIntegral spindrag * 2 / 200)
-            ]
     spinamount = _shellSpinAmount params
     thrustdelay = _shellThrustDelay params
     spindrag = _shellSpinDrag params