Stop inanimate objects from opening walls

src/Dodge/Creature/Property.hs

@@ -0,0 +1,20 @@
+module Dodge.Creature.Property
+    where
+import Dodge.Data
+
+import Geometry
+
+import Control.Lens
+
+crIsArmouredFrom :: Point2 -> Creature -> Bool
+crIsArmouredFrom p cr 
+    = p /= _crPos cr 
+        && any (\it -> it ^? itIdentity == Just FrontArmour) (_crInv cr)
+        && angleVV (unitVectorAtAngle $ _crDir cr) (p -.- _crPos cr) < pi/2
+-- even though angleVV can generate NaN, the comparison seems to deal with it
+
+crOnSeg :: Point2 -> Point2 -> Creature -> Bool
+crOnSeg p1 p2 cr = circOnLine p1 p2 (_crPos cr) (_crRad cr)
+
+crNearSeg :: Float -> Point2 -> Point2 -> Creature -> Bool
+crNearSeg d p1 p2 cr = circOnLine p1 p2 (_crPos cr) (_crRad cr + d)