Attempt to incorporate free link positions into placement chain

src/Dodge/LevelGen.hs

@@ -5,6 +5,7 @@ module Dodge.LevelGen
     ( shiftPlacement
     , shiftPointBy
     , placeSpot
+    , invShiftPointBy
     ) where
 import Dodge.Data
 import Dodge.LevelGen.Block
@@ -77,6 +78,9 @@ placeWallPoly ps wl = rmCrossPaths . over walls (addWalls ps wl)
 shiftPointBy :: (Point2,Float) -> Point2 -> Point2
 shiftPointBy (pos,rot) p = pos +.+ rotateV rot p
 
+invShiftPointBy :: (Point2,Float) -> Point2 -> Point2
+invShiftPointBy (p1,r) p2 = rotateV (-r) $ p2 -.- p1
+
 shiftPoint3By :: (Point2,Float) -> Point3 -> Point3
 shiftPoint3By (pos,rot) (V3 x y z) = addZ z $ pos +.+ rotateV rot (V2 x y)
 
@@ -119,7 +123,6 @@ placeBt bt p a w = (i , over buttons addBT w)
     i = IM.newKey $ _buttons w
     addBT xs = IM.insert i (f bt) xs
     f = (btRot +~ a) . (btPos %~ ( (p +.+) . rotateV a )) . (btID .~ i)
-    --addBT bts = IM.insert (IM.newKey bts) (bt {_btPos = p, _btRot = rot, _btID = IM.newKey bts}) bts
 {- Creates a floor item at a given point.
 Assigns an id correctly.  -}
 placeFlIt