Mapper, ARHUD, radar sweeps update. Add dropper items

src/Dodge/RadarSweep/Draw.hs

@@ -1,15 +1,26 @@
-module Dodge.RadarSweep.Draw where
+module Dodge.RadarSweep.Draw (
+    drawRadarSweep,
+) where
 
+import Control.Lens
+import Data.Maybe
 import Dodge.Data.RadarSweep
 import Geometry
 import Picture
 
+-- I have taken shortcuts in determining whether this is drawn or not wrt to the
+-- linked ARHUD: it needs to have existed at the sweeps original creation, then
+-- the sweep is drawn
 drawRadarSweep :: RadarSweep -> Picture
-drawRadarSweep pt = setLayer DebugLayer $ fold 
-        [ colHelper 0.1 $ uncurryV translate p $ thickCircle r 15
-        , colHelper 0.06 $ uncurryV translate p $ thickCircle (r -5) 5
-        , colHelper 0.03 $ uncurryV translate p $ thickCircle (r -10) 5
-        ]
+drawRadarSweep pt
+    | isJust (pt ^. rsAR) =
+        setLayer DebugLayer $
+            fold
+                [ colHelper 0.1 $ uncurryV translate p $ thickCircle r 15
+                , colHelper 0.06 $ uncurryV translate p $ thickCircle (r -5) 5
+                , colHelper 0.03 $ uncurryV translate p $ thickCircle (r -10) 5
+                ]
+    | otherwise = mempty
   where
     col = rsObjectColor $ _rsObject pt
     p = _rsPos pt