Allow determination of attach item relative positions

src/Dodge/Creature.hs

@@ -280,6 +280,7 @@ testInventory =
 stackedInventory :: [Item]
 stackedInventory =
     [ torch
+    , torch
     , remoteScreen
     , megaShellMag
     , targetingScope TARGETLASER

src/Dodge/Creature/State.hs

@@ -266,7 +266,7 @@ chainLinkOrientation
 chainLinkOrientation mo par (ILink lt f) child = do
     (p,q) <- mo
     (p1,q1) <- f par lt child
-    return (p + Q.rotate q p1, q * q1)
+    return (p + Q.rotate q1 p1, q * q1)
 
 updateRootItem' :: LabelDoubleTree ItemLink Item -> Creature -> World -> World
 updateRootItem' itmtree cr = ldtPropagateFold chainLinkOrientation chainLinkOrientation
@@ -280,7 +280,10 @@ updateItemWithOrientation cr m itm = case _itType itm of
     _ -> id
 
 testtorch :: Creature -> Maybe (Point3, Q.Quaternion Float) -> World -> World
-testtorch cr = maybe id $ \(pos,_) -> muzFlareAt yellow (_crPos cr `v2z` 0 + rotate3z (_crDir cr) pos) (_crDir cr)
+testtorch cr m = fromMaybe id $ do
+    (pos,q) <- m 
+    let d = _crDir cr + argV (Q.qToV2 q)
+    return $ muzFlareAt yellow (_crPos cr `v2z` 0 + rotate3z d pos) d
 
 itemInvSideEffect :: Creature -> Item -> World -> World
 itemInvSideEffect cr itm = case _itType itm of

src/Dodge/Item/Orientation.hs

@@ -5,22 +5,25 @@ module Dodge.Item.Orientation
 import Dodge.Data.ComposedItem
 import Geometry.Data
 import Dodge.Data.Item
-import qualified Linear.Quaternion as Q
+import qualified Quaternion as Q
 
 orientChild :: Item -> (Point3, Q.Quaternion Float)
 orientChild itm = case _itType itm of
-    HELD TORCH -> (V3 5 0 0,Q.axisAngle (V3 1 0 0) 0)
-    _ -> (0,Q.axisAngle (V3 1 0 0) 0)
+    HELD TORCH -> (V3 0 20 0,Q.qID)
+    _ -> (0,Q.qID)
 
 orientByLink :: Item -> ComposeLinkType -> (Point3, Q.Quaternion Float)
 orientByLink itm lt = case (_itType itm,lt) of
-    (HELD FLAMETHROWER, AmmoInLink{}) -> (V3 4 (-6) 0, Q.axisAngle (V3 1 0 0) 0)
-    (HELD _,AmmoInLink{}) -> (V3 7 (-2) 0, Q.axisAngle (V3 1 0 0) 0)
-    (HELD _,WeaponScopeLink) -> (V3 5 0 5, Q.axisAngle (V3 1 0 0) 0)
-    _ -> (0,Q.axisAngle (V3 1 0 0) 0)
+    (HELD FLAMETHROWER, AmmoInLink{}) -> (V3 4 (-6) 0, Q.qID)
+    (HELD _,AmmoInLink{}) -> (V3 7 (-2) 0, Q.qID)
+    (HELD _,WeaponScopeLink) -> (V3 5 0 5, Q.qID)
+    _ -> (0,Q.qID)
 
 orientAttachment :: Item -> ComposeLinkType -> Item -> Maybe (Point3, Q.Quaternion Float)
-orientAttachment par lnk ch = Just (t1 + Q.rotate q1 t2, q1 * q2)
+orientAttachment par lnk ch = Just $ case (_itType par,lnk,_itType ch) of
+    (HELD BURSTRIFLE,_,HELD TORCH) -> (V3 20 0 0, Q.qID)
+    (HELD LAUNCHER,_,HELD TORCH) -> (V3 0 20 0, Q.qID)
+    _ -> (t1 + Q.rotate q1 t2, q1 * q2)
   where
     (t1,q1) = orientByLink par lnk
     (t2,q2) = orientChild ch

src/Quaternion.hs

@@ -11,6 +11,8 @@ The warnings have been disabled.
 -}
 module Quaternion (
     qID,
+    qToV3,
+    qToV2,
     rotateToZ,
     vToQuat,
     module Linear.Quaternion,
@@ -43,6 +45,12 @@ vToQuat a b
   where
     cprod = crossProd a b
 
+qToV3 :: Q.Quaternion Float -> Point3
+qToV3 q = Q.rotate q (V3 1 0 0)
+
+qToV2 :: Q.Quaternion Float -> Point2
+qToV2 = (\(V3 x y _) -> V2 x y) . qToV3
+
 qID :: Q.Quaternion Float
 qID = Q.axisAngle (V3 1 0 0) 0