Converted from roc to curvature

lib/Petzval/System.hs

@@ -65,12 +65,12 @@ instance Num a => Monoid (Seidel a) where
 -- | Initial matrix is [ h_ h; u_ u ]
 seidel' :: (RealFloat a, Mode a, Scalar a ~ Double, Epsilon a) => M22 a -> Element BakedIOR a -> (M22 a, Seidel a)
 seidel' rays (s@Stop{}) = (thicknessRTM s !*! rays, mempty)
-seidel' rays (s@Surface{_material=BakedIOR n1 n2,_roc=roc}) = (rays'', Seidel {sphr,coma,asti,fcur,dist})
+seidel' rays (s@Surface{_material=BakedIOR n1 n2,_curvature=curvature}) = (rays'', Seidel {sphr,coma,asti,fcur,dist})
   where rays' = refractionRTM s !*! rays
         rays'' = thicknessRTM s !*! rays'
         marg = column _y
         chief = column _x
-        _i = to (\ray -> (ray ^. _x) / roc + (ray ^. _y))
+        _i = to (\ray -> (ray ^. _x) / curvature + (ray ^. _y))
         a = auto n1 * (rays ^. marg._i)
         abar = auto n1 * (rays ^. chief._i)
         h = rays ^. marg._x
@@ -82,11 +82,11 @@ seidel' rays (s@Surface{_material=BakedIOR n1 n2,_roc=roc}) = (rays'', Seidel {s
         sphr = a ^ 2 * h * δun
         coma = -a * abar * h * δun
         asti = -abar^2 * h * δun
-        fcur = lagrange^2 / roc * δ1n
+        fcur = lagrange^2 * curvature * δ1n
         -- Normally this is defined as abar/a * (asti*fcur)
         -- However, a is 0 whenever the marginal ray is normal to the surface
         -- Thus, we use this formula from Kidger
-        dist = -abar^3 * h * δ1n2 + (rays^. chief._x) * abar * (2 * h * abar - rays ^. chief._x * a) * δ1n / roc
+        dist = -abar^3 * h * δ1n2 + (rays^. chief._x) * abar * (2 * h * abar - rays ^. chief._x * a) * δ1n * curvature
         -- TODO: evaluate at other IORs
         -- cbas = h  (n2 - n1) / n1
         -- c1 =