Work on boundaries for dragging windows

src/Dodge/Data/ScreenPos.hs

@@ -10,7 +10,7 @@ import Control.Lens
 -- a spScreenOff of 1 is the full length of the screen
 -- for eg see fromTopLeft
 data ScreenPos = ScreenPos
-    { _spScreenOff :: Point2
+    { _spScreenOff :: Point2 -- from bottom left
     , _spPixelOff :: Point2
     }
 makeLenses ''ScreenPos

src/Dodge/Data/SelectionList.hs

@@ -9,12 +9,13 @@ import Data.IntMap.Strict (IntMap)
 import Dodge.Data.CardinalPoint
 import Dodge.Data.ScreenPos
 import Picture.Data
+import Linear
 
 data LDParams = LDP -- List display parameters
     { _ldpPos :: ScreenPos
     , _ldpScale :: Float
     , _ldpVerticalGap :: Float
-    , _ldpBorder :: Maybe (Int,Int) -- the Ints give height and width for a border
+    , _ldpSize :: Maybe (V2 Int)
     }
 
 data CursorDisplay