Allow tweaking z buffer when rendering polygon, improve explosion render

src/Dodge/Item/Weapon/Laser.hs

@@ -3,7 +3,7 @@ module Dodge.Item.Weapon.Laser
     where
 import Dodge.Data
 import Dodge.Picture
-import Dodge.Picture.Layer
+--import Dodge.Picture.Layer
 import Dodge.Item.Attachment.Data
 --import Dodge.Base
 import Dodge.SoundLogic
@@ -56,7 +56,7 @@ moveLaser
     -> (World, Maybe Particle)
 moveLaser phaseV pos dir w pt
     = ( set randGen g $ hitEffect w
-      , Just pt {_ptDraw = const $ onLayer PtLayer pic ,_ptUpdate' = ptTimer' 0 }
+      , Just pt {_ptDraw = const pic ,_ptUpdate' = ptTimer' 0 }
       )
   where 
     xp = pos +.+ 800 *.* unitVectorAtAngle dir
@@ -106,7 +106,7 @@ moveLaser phaseV pos dir w pt
           Just (p,E3x2 wl) -> createSpark 8 colID (p +.+ safeNormalizeV (pos -.- p))
                                                       (reflectDir wl) Nothing
           _   -> id
-    pic = pictures 
+    pic = setDepth 20 $ pictures 
         [ fadeLine pos (head ps) 0.2 40 yellow
         , setLayer 1 $ color (withAlpha 0.9 white) $ vThickLine (pos:ps)
         , setLayer 1 $ color (withAlpha 0.5 yellow) $ vvThickLine (pos:ps)

src/Dodge/Item/Weapon/Launcher.hs

@@ -98,7 +98,7 @@ doThrust pj w = w
     & randGen .~ g
     & projectiles . ix i . pjVel    %~ (\v -> accel +.+ frict *.* v)
     & soundFromPos (ShellSound i) newPos (fromIntegral smokeTrailSound) 1 250
-    & makeFlameletTimed (oldPos -.- vel) (vel +.+ rotateV (pi+sparkD) accel) Nothing 3 10
+    & makeFlameletTimed (oldPos -.- vel) 0 (vel +.+ rotateV (pi+sparkD) accel) Nothing 3 10
     & smokeGen
   where
     accel = _pjAcc pj
@@ -172,16 +172,11 @@ reduceSpinBy :: Float -> Projectile -> World -> World
 reduceSpinBy x pj = projectiles . ix (_pjID pj) .  pjSpin *~ x
 
 shellPic :: Projectile -> Picture
-shellPic pj
-    | t > 40    =  onLayerL [levLayer CrLayer - 2] 
-        $ uncurry translate pos $ rotate (argV accel) basePic 
-    | otherwise = onLayer PtLayer $ uncurry translate pos $ rotate (argV accel) basePic
+shellPic pj = setDepth 20 . uncurry translate pos $ rotate (argV accel) basePic
   where
     basePic = color black $ polygon [(-6,4),(-6,-4),(6,-4),(8,0),(6,4)]
     accel = _pjAcc pj
     pos = _pjPos pj
-    t = _pjTimer pj
-
 
 pjEffTimeRange
     :: (Int,Int)