Progressively reveal the map to the player

As the character walks around the map, progressively reveal the entities
on the map to them, using an algorithm based on well known
circle-rasterizing and line-rasterizing algorithms to calculate lines of
sight that are potentially obscured by walls.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/Xanthous/Entities/Environment.hs b/src/Xanthous/Entities/Environment.hs
index f5301f94adf2..90fa05315a57 100644
--- a/src/Xanthous/Entities/Environment.hs
+++ b/src/Xanthous/Entities/Environment.hs
@@ -7,7 +7,7 @@ import Test.QuickCheck
 import Brick (str)
 import Brick.Widgets.Border.Style (unicode)
 --------------------------------------------------------------------------------
-import Xanthous.Entities (Draw(..), entityIs)
+import Xanthous.Entities (Draw(..), entityIs, Entity(..))
 import Xanthous.Entities.Draw.Util
 import Xanthous.Data
 --------------------------------------------------------------------------------
@@ -16,6 +16,9 @@ data Wall = Wall
   deriving stock (Show, Eq, Ord, Generic, Enum)
   deriving anyclass (CoArbitrary, Function)
 
+instance Entity Wall where
+  blocksVision _ = True
+
 instance Arbitrary Wall where
   arbitrary = pure Wall