Add distance indicator for forcefield gun

src/Dodge/Item/Weapon/Utility.hs

@@ -147,19 +147,22 @@ forceFieldGun = defaultGun
     , _itUse = ruseInstant useForceFieldGun (HasHammer HammerUp)
         [ hammerCheckI , ammoCheckI , useAmmoAmount 1]
 --    , _itFloorPict = \_ -> (,) emptySH $ onLayer FlItLayer $ polygon $ map toV2 [(-4,-4),(-4,4),(4,4),(4,0),(0,0),(0,-4)]
-    , _itTargeting = targetRBPress
+    , _itTargeting = targetRBPress & tgDraw .~ targetDistanceDraw
     , _itParams = ParamMID Nothing
     }
-
+-- I believe because the targeting returns to nothing straight after you release
+-- the rmb, it is possible for this to do nothing
+-- TODO investigate more and fix
 useForceFieldGun :: Item -> Creature -> World -> World
-useForceFieldGun itm cr w = w
-    & walls %~ IM.insertWith (\_ x -> x) i forceField {_wlID = i}
-    & creatures . ix (_crID cr) . crInv . ix (fromJust (_itInvPos itm)) . itParams . paramMID ?~ i
-    & moveWallIDUnsafe i wlline
+useForceFieldGun itm cr w = fromMaybe w $ do 
+    a <- _tgPos $ _itTargeting itm
+    let wlline = (a,mouseWorldPos w)
+    return $ w 
+        & walls %~ IM.insertWith (\_ x -> x) i forceField {_wlID = i}
+        & creatures . ix (_crID cr) . crInv . ix (fromJust (_itInvPos itm)) . itParams . paramMID ?~ i
+        & moveWallIDUnsafe i wlline
   where
     i = fromMaybe (IM.newKey (_walls w)) $ itm ^? itParams . paramMID . _Just
-    a = fromJust . _tgPos $ _itTargeting itm
-    wlline = (a,mouseWorldPos w)
 
 -- grapGun = defaultGun 
 --     { _itName = "grapGun"