From 8eb050d10ad0e3f732cb0b95b7f03632e420113e Mon Sep 17 00:00:00 2001
From: Nolan Darilek <nolan@thewordnerd.info>
Date: Sun, 25 Aug 2024 17:59:57 -0500
Subject: [PATCH] Various visibility fixes.

---
 src/visibility.rs | 32 +++++++++++++++++++++++++++++---
 1 file changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/visibility.rs b/src/visibility.rs
index ba40a15..0f360d3 100644
--- a/src/visibility.rs
+++ b/src/visibility.rs
@@ -146,7 +146,30 @@ impl Viewshed {
                 };
                 if let Some((opacity, coord_entities)) = result {
                     for e in &coord_entities {
-                        new_visible_entities.insert(*e);
+                        let mut should_insert = true;
+                        if coord_entities.len() > 1 {
+                            let start = start.translation().truncate();
+                            let dest = Vec2::new(coord.x as f32, coord.y as f32);
+                            let dir = dest - start;
+                            rapier_context.intersections_with_ray(
+                                start,
+                                dir,
+                                1.,
+                                true,
+                                QueryFilter::new()
+                                    .exclude_sensors()
+                                    .exclude_collider(*viewer_entity)
+                                    .exclude_collider(*e)
+                                    .predicate(&|e| visible_query.contains(e)),
+                                |_, _| {
+                                    should_insert = false;
+                                    false
+                                },
+                            );
+                        }
+                        if should_insert {
+                            new_visible_entities.insert(*e);
+                        }
                     }
                     opacity
                 } else {
@@ -187,7 +210,7 @@ impl Viewshed {
     }
 }
 
-#[derive(Component, Clone, Copy, Debug, Deref, DerefMut, Reflect)]
+#[derive(Component, Clone, Copy, Debug, Deref, DerefMut, Eq, PartialEq, Reflect)]
 #[reflect(Component)]
 pub struct Visible(pub u8);
 
@@ -437,6 +460,9 @@ impl<MapData: 'static + Clone + Default + Send + Sync> Plugin for VisibilityPlug
                     update_revealed_tiles::<MapData>,
                 ),
             )
-            .add_systems(FixedPostUpdate, (log_visible, viewshed_removed, remove_visible));
+            .add_systems(
+                FixedPostUpdate,
+                (log_visible, viewshed_removed, remove_visible),
+            );
     }
 }