Work on weapon positioning

src/Quaternion.hs

@@ -16,6 +16,7 @@ module Quaternion (
     comp,
     prePos,
     module Linear.Quaternion,
+    qNoRoll,
 ) where
 
 import Geometry.Vector
@@ -24,6 +25,8 @@ import Geometry.Data
 import Geometry.Vector3D
 import Linear.Quaternion
 import qualified Linear.Quaternion as Q
+import Control.Lens
+import Linear
 
 instance ToJSON a => ToJSON (Q.Quaternion a) where
     toEncoding = genericToEncoding defaultOptions
@@ -46,6 +49,17 @@ vToQuat a b
   where
     cprod = crossProd a b
 
+qNoRoll :: Point3 -> Q.Quaternion Float
+--qNoRoll x = qz (argV $ x ^. _xy) * Q.axisAngle (V3 0 (-1) 0) (argV (V2 (x ^. _z) (norm (x ^. _xy))))
+qNoRoll x =  qNoRoll2 x * qNoRoll1 x
+--qNoRoll x = Q.axisAngle (V3 0 1 0) (argV (V2 (x ^. _z) (norm (x ^. _xy)))) * qz (argV $ x ^. _xy)
+--
+qNoRoll1 :: Point3 -> Q.Quaternion Float
+qNoRoll1 x =  Q.axisAngle (V3 0 (-1) 0) . argV $ V2 (norm (x ^. _xy)) (x ^. _z)
+
+qNoRoll2 :: Point3 -> Q.Quaternion Float
+qNoRoll2 x =  qz (argV $ x ^. _xy)
+
 qToV3 :: Q.Quaternion Float -> Point3
 qToV3 q = Q.rotate q (V3 1 0 0)