From d33f26d31c015b8569683afae84380f3817b27e0 Mon Sep 17 00:00:00 2001
From: Nolan Darilek <nolan@thewordnerd.info>
Date: Mon, 23 Aug 2021 10:14:03 -0500
Subject: [PATCH] Visibility system cleanup.

---
 src/visibility.rs | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/src/visibility.rs b/src/visibility.rs
index a0f36e5..a53ce19 100644
--- a/src/visibility.rs
+++ b/src/visibility.rs
@@ -112,7 +112,6 @@ fn update_viewshed(
     let mut context: Context<u8> = Context::default();
     let vision_distance = vision_distance::Circle::new(viewshed.range);
     let coord = Coord::new(start.x_i32(), start.y_i32());
-    viewshed.visible.clear();
     let shape = Cuboid::new(Vec2::new(0.49, 0.49).into());
     let range = viewshed.range as f32;
     let collider_set = QueryPipelineColliderComponentsSet(&collider_query);
@@ -148,6 +147,7 @@ fn update_viewshed(
         );
         opacity
     });
+    let mut new_visible = HashSet::new();
     context.for_each_visible(
         coord,
         &visibility_grid,
@@ -155,13 +155,16 @@ fn update_viewshed(
         vision_distance,
         255,
         |coord, _directions, _visibility| {
-            viewshed.visible.insert((coord.x, coord.y));
+            new_visible.insert((coord.x, coord.y));
         },
     );
+    if viewshed.visible != new_visible {
+        viewshed.visible = new_visible;
+    }
 }
 
 fn update_viewshed_for_coordinates(
-    visible: Query<&Coordinates, (Changed<Coordinates>, With<BlocksVisibility>)>,
+    visible: Query<(Entity, &Coordinates), (Changed<Coordinates>, With<BlocksVisibility>)>,
     mut viewers: Query<(Entity, &mut Viewshed, &Coordinates)>,
     map: Query<&Map>,
     query_pipeline: Res<QueryPipeline>,
@@ -169,9 +172,11 @@ fn update_viewshed_for_coordinates(
     blocks_visibility: Query<&BlocksVisibility>,
     coordinates_query: Query<&Coordinates>,
 ) {
-    for coordinates in visible.iter() {
+    for (visible_entity, coordinates) in visible.iter() {
         for (viewer_entity, mut viewshed, start) in viewers.iter_mut() {
-            if coordinates.distance(start) > viewshed.range as f32 {
+            if viewer_entity == visible_entity
+                || coordinates.distance(start) > viewshed.range as f32
+            {
                 continue;
             }
             if let Ok(map) = map.single() {
@@ -273,12 +278,7 @@ fn log_visible(
     for timer in recently_lost.values_mut() {
         timer.tick(time.delta());
     }
-    let recently_lost_clone = recently_lost.clone();
-    for (entity, timer) in recently_lost_clone.iter() {
-        if timer.finished() {
-            recently_lost.remove(&entity);
-        }
-    }
+    recently_lost.retain(|_, v| !v.finished());
     let mut new_seen = HashSet::new();
     if let Ok(mut log) = log.single_mut() {
         for (viewer_entity, viewshed, coordinates, transform) in viewers.iter() {