Add trajectory to grenades, various refactoring

src/Dodge/Default/Shell.hs

@@ -4,15 +4,16 @@ import Dodge.Data
 import Picture
 import Geometry.Data
 
-defaultShell :: Projectile
+defaultShell :: Prop
 defaultShell = Shell
     { _pjPos = V2 0 0
+    , _pjZ   = 20
     , _pjStartPos = V2 0 0
     , _pjVel = V2 0 0
     , _pjAcc = V2 0 0
     , _pjDir = 0
     , _pjSpin = 0
-    , _pjDraw = const blank
+    , _prDraw = const (mempty, blank)
     , _pjID = 0
     , _pjTimer = 0
     , _pjUpdate = const id

src/Dodge/Default/Weapon.hs

@@ -58,6 +58,6 @@ defaultShellAmmo = ShellAmmo
     { _amPayload = const id
     , _amString = "Shell"
     , _amPjParams = []
-    , _amPjDraw = const blank
+    , _amPjDraw = const mempty
     , _amParamSel = 0
     }

src/Dodge/Default/World.hs

@@ -33,7 +33,7 @@ defaultWorld = World
     , _clouds = []
     , _cloudsZone = Zone IM.empty
     , _itemPositions = IM.empty
-    , _projectiles = IM.empty
+    , _props = IM.empty
     , _particles = []
     , _walls = IM.empty
     , _wallsZone = Zone IM.empty