From 42912e59a8a11ada5d7ace2a213a1efcb2712818 Mon Sep 17 00:00:00 2001
From: Nolan Darilek <nolan@thewordnerd.info>
Date: Tue, 21 Sep 2021 06:38:51 -0500
Subject: [PATCH] Refactor visibility to be collider and event-based.

---
 src/exploration.rs |   4 +-
 src/sound.rs       |  25 ++--
 src/visibility.rs  | 300 ++++++++++++++++++++++++++++++++++-----------
 3 files changed, 243 insertions(+), 86 deletions(-)

diff --git a/src/exploration.rs b/src/exploration.rs
index 014df57..a70e45c 100644
--- a/src/exploration.rs
+++ b/src/exploration.rs
@@ -95,7 +95,7 @@ where
                 let (x, y) = **coordinates;
                 let x = x as i32;
                 let y = y as i32;
-                if viewshed.visible.contains(&(x, y)) {
+                if viewshed.is_point_visible(&(x, y)) {
                     types.push(*t);
                 }
             }
@@ -176,7 +176,7 @@ where
                     let (x, y) = ***coordinates;
                     let x = x as i32;
                     let y = y as i32;
-                    viewshed.visible.contains(&(x, y))
+                    viewshed.is_point_visible(&(x, y))
                 })
                 .collect::<Vec<(&Coordinates, &ExplorationType)>>();
             features.sort_by(|(c1, _), (c2, _)| c1.partial_cmp(c2).unwrap());
diff --git a/src/sound.rs b/src/sound.rs
index 745ebc7..5cacb93 100644
--- a/src/sound.rs
+++ b/src/sound.rs
@@ -8,7 +8,7 @@ use rand::random;
 use crate::{
     core::{Coordinates, CoreConfig, Player, PointLike},
     exploration::ExplorationFocused,
-    visibility::Viewshed,
+    visibility::{Viewshed, VisibleEntities},
 };
 
 #[derive(Clone, Debug, Reflect)]
@@ -151,14 +151,14 @@ fn sound_icon<S>(
     config: Res<SoundConfig<S>>,
     state: Res<State<S>>,
     time: Res<Time>,
-    viewers: Query<&Viewshed, With<Player>>,
+    viewers: Query<&VisibleEntities, With<Player>>,
     mut icons: Query<(
+        Entity,
         &mut SoundIcon,
         Option<&Coordinates>,
         Option<&Parent>,
         &mut Sound,
     )>,
-    coordinates_storage: Query<&Coordinates>,
     buffers: Res<Assets<Buffer>>,
 ) where
     S: Component + Clone + Debug + Eq + Hash,
@@ -168,18 +168,14 @@ fn sound_icon<S>(
     {
         return;
     }
-    for viewer in viewers.iter() {
-        for (mut icon, coordinates, parent, mut sound) in icons.iter_mut() {
-            let coords = if let Some(coordinates) = coordinates {
-                *coordinates
-            } else if let Some(parent) = parent {
-                *coordinates_storage
-                    .get(**parent)
-                    .expect("If `SoundIcon` is a child, its parent must have `Coordinates`")
+    for visible in viewers.iter() {
+        for (icon_entity, mut icon, coordinates, parent, mut sound) in icons.iter_mut() {
+            let entity = if coordinates.is_some() {
+                icon_entity
             } else {
-                panic!("No `Coordinates` on `SoundIcon` or parent");
+                **parent.unwrap()
             };
-            if viewer.is_visible(&coords) {
+            if visible.contains(&entity) {
                 let looping = sound.looping;
                 if looping {
                     sound.state = SoundState::Playing;
@@ -193,7 +189,6 @@ fn sound_icon<S>(
                 let buffer = buffers.get_handle(icon.sound);
                 sound.looping = icon.interval.is_none();
                 if sound.buffer != buffer {
-                    sound.stop();
                     sound.buffer = buffer;
                 }
                 sound.gain = icon.gain;
@@ -201,6 +196,8 @@ fn sound_icon<S>(
                 sound.reference_distance = icon.reference_distance;
                 sound.max_distance = icon.max_distance;
                 sound.rolloff_factor = icon.rolloff_factor;
+            } else {
+                sound.state = SoundState::Stopped;
             }
         }
     }
diff --git a/src/visibility.rs b/src/visibility.rs
index 540a2ec..097129a 100644
--- a/src/visibility.rs
+++ b/src/visibility.rs
@@ -1,6 +1,7 @@
 use std::collections::{HashMap, HashSet};
 
 use bevy::prelude::*;
+use bevy_rapier2d::na::UnitComplex;
 use coord_2d::{Coord, Size};
 use derive_more::{Deref, DerefMut};
 use shadowcast::{vision_distance, Context, InputGrid};
@@ -10,6 +11,7 @@ use crate::{
     core::{Angle, Coordinates, Player, PointLike},
     log::Log,
     map::{ITileType, Map, MapConfig},
+    utils::target_and_other,
 };
 
 #[derive(Clone, Copy, Debug, Deref, DerefMut, Reflect)]
@@ -21,6 +23,7 @@ impl Default for BlocksVisibility {
         Self(u8::MAX)
     }
 }
+
 #[derive(Clone, Copy, Debug, Default, Reflect)]
 #[reflect(Component)]
 pub struct DontLogWhenVisible;
@@ -31,29 +34,58 @@ pub struct RevealedTiles(pub Vec<bool>);
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct Viewshed {
-    pub visible: HashSet<(i32, i32)>,
     pub range: u32,
+    pub visible_points: HashSet<(i32, i32)>,
 }
 
 impl Default for Viewshed {
     fn default() -> Self {
         Self {
             range: 15,
-            visible: HashSet::new(),
+            visible_points: HashSet::new(),
         }
     }
 }
 
 impl Viewshed {
-    pub fn is_visible(&self, point: &dyn PointLike) -> bool {
-        self.visible.contains(&point.into())
+    pub fn is_point_visible(&self, point: &dyn PointLike) -> bool {
+        self.visible_points.contains(&point.into())
     }
 }
 
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+struct VisibilityCollider;
+
+#[derive(Clone, Debug, Default, Deref, DerefMut)]
+pub struct VisibleEntities(HashSet<Entity>);
+
 #[derive(Clone, Debug, Default, Deref, DerefMut, Reflect)]
 #[reflect(Component)]
 pub struct VisibleTiles(pub Vec<bool>);
 
+#[derive(Bundle, Default)]
+pub struct ViewshedBundle {
+    pub viewshed: Viewshed,
+    pub visible_entities: VisibleEntities,
+}
+
+impl ViewshedBundle {
+    pub fn new(range: u32) -> Self {
+        Self {
+            viewshed: Viewshed {
+                range,
+                ..Default::default()
+            },
+            ..Default::default()
+        }
+    }
+}
+
+pub enum VisibilityChanged {
+    Gained { viewer: Entity, viewed: Entity },
+    Lost { viewer: Entity, viewed: Entity },
+}
+
 impl PointLike for Coord {
     fn x(&self) -> f32 {
         self.x as f32
@@ -80,6 +112,90 @@ fn add_visibility_indices(
     }
 }
 
+fn viewshed_added(mut commands: Commands, query: Query<Entity, Added<Viewshed>>) {
+    for entity in query.iter() {
+        let id = commands.spawn().insert(VisibilityCollider).id();
+        commands.entity(entity).push_children(&[id]);
+    }
+}
+
+fn viewshed_changed(
+    mut commands: Commands,
+    query: Query<(Entity, &Viewshed, &RigidBodyPosition), Changed<Viewshed>>,
+    mut collider_data: Query<
+        (&Parent, Entity, Option<&mut ColliderShape>),
+        With<VisibilityCollider>,
+    >,
+) {
+    for (entity, viewshed, position) in query.iter() {
+        for (parent, child_entity, collider_shape) in collider_data.iter_mut() {
+            if **parent != entity {
+                continue;
+            }
+            if viewshed.visible_points.len() < 2 {
+                commands.entity(child_entity).remove::<ColliderShape>();
+            } else {
+                let position = position.position;
+                let mut points = vec![];
+                for p in &viewshed.visible_points {
+                    points.push(point!(
+                        position.translation.x - p.x(),
+                        position.translation.y - p.y()
+                    ));
+                }
+                if let Some(shape) = ColliderShape::convex_hull(&points) {
+                    //println!("Shape for {:?}", points);
+                    if let Some(mut collider_shape) = collider_shape {
+                        *collider_shape = shape;
+                    } else {
+                        //println!("Creating collider at {:?}", coordinates.i32());
+                        commands.entity(child_entity).insert_bundle(ColliderBundle {
+                            collider_type: ColliderType::Sensor,
+                            shape,
+                            flags: ActiveEvents::INTERSECTION_EVENTS.into(),
+                            ..Default::default()
+                        });
+                    }
+                }
+            }
+        }
+    }
+}
+
+fn lock_rotation(
+    mut query: Query<(&Parent, &mut ColliderPosition), With<VisibilityCollider>>,
+    positions: Query<&RigidBodyPosition>,
+) {
+    for (parent, mut position) in query.iter_mut() {
+        if let Ok(parent_position) = positions.get(**parent) {
+            let delta = parent_position
+                .position
+                .rotation
+                .angle_to(&UnitComplex::new(0.));
+            println!("Syncing: {:?}", delta);
+            position.rotation = UnitComplex::new(delta);
+        }
+    }
+}
+
+fn viewshed_removed(
+    mut commands: Commands,
+    query: RemovedComponents<Viewshed>,
+    children: Query<&Children>,
+    collider_shapes: Query<Entity, With<VisibilityCollider>>,
+) {
+    for entity in query.iter() {
+        if let Ok(children) = children.get(entity) {
+            for child in children.iter() {
+                if collider_shapes.get(*child).is_ok() {
+                    commands.entity(*child).despawn_recursive();
+                    break;
+                }
+            }
+        }
+    }
+}
+
 pub struct VisibilityGrid<'a, F>(pub &'a Map, pub F);
 
 impl<'a, F> InputGrid for VisibilityGrid<'a, F>
@@ -128,7 +244,6 @@ fn update_viewshed(
             Some(&|v| v.entity() != *viewer_entity && blocks_visibility.get(v.entity()).is_ok()),
             |handle| {
                 if let Ok(blocks_visibility) = blocks_visibility.get(handle.entity()) {
-                    // println!("Visibility blocked at {:?}", coord);
                     opacity = **blocks_visibility;
                     false
                 } else {
@@ -149,8 +264,8 @@ fn update_viewshed(
             new_visible.insert((coord.x, coord.y));
         },
     );
-    if viewshed.visible != new_visible {
-        viewshed.visible = new_visible;
+    if viewshed.visible_points != new_visible {
+        viewshed.visible_points = new_visible;
     }
 }
 
@@ -208,14 +323,18 @@ fn update_viewshed_for_start(
 
 fn remove_blocks_visibility(
     removed: RemovedComponents<BlocksVisibility>,
-    mut viewers: Query<(Entity, &mut Viewshed, &Coordinates)>,
+    mut viewers: Query<(Entity, &mut Viewshed, &mut VisibleEntities, &Coordinates)>,
     map: Query<&Map>,
     query_pipeline: Res<QueryPipeline>,
     collider_query: QueryPipelineColliderComponentsQuery,
     blocks_visibility: Query<&BlocksVisibility>,
 ) {
-    for _ in removed.iter() {
-        for (viewer_entity, mut viewshed, start) in viewers.iter_mut() {
+    for removed in removed.iter() {
+        for (viewer_entity, mut viewshed, mut visible_entities, start) in viewers.iter_mut() {
+            if !visible_entities.contains(&removed) {
+                continue;
+            }
+            visible_entities.remove(&removed);
             if let Ok(map) = map.single() {
                 update_viewshed(
                     &viewer_entity,
@@ -240,7 +359,7 @@ fn update_visible_and_revealed_tiles(
             for t in visible_tiles.iter_mut() {
                 *t = false
             }
-            for v in viewshed.visible.iter() {
+            for v in viewshed.visible_points.iter() {
                 let idx = v.to_index(map.width);
                 if idx >= revealed_tiles.len() || idx >= visible_tiles.len() {
                     continue;
@@ -252,73 +371,111 @@ fn update_visible_and_revealed_tiles(
     }
 }
 
+fn intersection(
+    mut events: EventReader<IntersectionEvent>,
+    colliders: Query<&Parent, With<VisibilityCollider>>,
+    mut viewers: Query<&mut VisibleEntities>,
+    names: Query<&Name>,
+    parents: Query<&Parent>,
+    mut visibility_changed: EventWriter<VisibilityChanged>,
+) {
+    for event in events.iter() {
+        println!("{:?}", event);
+        if let Some((visibility_collider, other)) =
+            target_and_other(event.collider1.entity(), event.collider2.entity(), |v| {
+                colliders.get(v).is_ok()
+            })
+        {
+            if let Ok(parent) = colliders.get(visibility_collider) {
+                if let Ok(mut visible_entities) = viewers.get_mut(**parent) {
+                    if event.intersecting {
+                        println!("{:?} is visible: {:?}", other, names.get(other));
+                        if let Ok(p) = parents.get(other) {
+                            println!("{:?}", names.get(**p));
+                        }
+                        visibility_changed.send(VisibilityChanged::Gained {
+                            viewer: **parent,
+                            viewed: other,
+                        });
+                        visible_entities.insert(other);
+                    } else {
+                        println!("{:?} is not visible", other);
+                        visibility_changed.send(VisibilityChanged::Lost {
+                            viewer: **parent,
+                            viewed: other,
+                        });
+                        visible_entities.remove(&other);
+                    }
+                }
+            }
+        }
+    }
+}
+
 fn log_visible(
     time: Res<Time>,
-    mut seen: Local<HashSet<Entity>>,
     mut recently_lost: Local<HashMap<Entity, Timer>>,
-    query_pipeline: Res<QueryPipeline>,
-    collider_query: QueryPipelineColliderComponentsQuery,
+    mut events: EventReader<IntersectionEvent>,
     mut log: Query<&mut Log>,
-    viewers: Query<(Entity, &Viewshed, &Coordinates, &Transform), With<Player>>,
-    names: Query<&Name>,
-    dont_log_when_visible: Query<&DontLogWhenVisible>,
+    viewer_colliders: Query<&Parent, With<VisibilityCollider>>,
+    viewers: Query<(Entity, &Coordinates, &Transform), (With<Player>, With<Viewshed>)>,
+    viewed: Query<
+        (
+            Entity,
+            &Name,
+            Option<&RigidBodyPosition>,
+            Option<&ColliderPosition>,
+        ),
+        Without<DontLogWhenVisible>,
+    >,
 ) {
     for timer in recently_lost.values_mut() {
         timer.tick(time.delta());
     }
-    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() {
-            let collider_set = QueryPipelineColliderComponentsSet(&collider_query);
-            let shape = Cuboid::new(Vec2::new(0.49, 0.49).into());
-            for viewed_coordinates in &viewshed.visible {
-                if coordinates.distance(viewed_coordinates) >= viewshed.range as f32 - 0.1 {
-                    continue;
-                }
-                let shape_pos = (
-                    Vec2::new(viewed_coordinates.x() + 0.5, viewed_coordinates.y() + 0.5),
-                    0.0,
-                )
-                    .into();
-                query_pipeline.intersections_with_shape(
-                    &collider_set,
-                    &shape_pos,
-                    &shape,
-                    InteractionGroups::all(),
-                    Some(&|v| v.entity() != viewer_entity),
-                    |handle| {
-                        let entity = handle.entity();
-                        if recently_lost.contains_key(&entity) {
-                            new_seen.insert(entity);
-                            recently_lost.remove(&entity);
-                            return true;
-                        }
-                        if let Ok(name) = names.get(entity) {
-                            if !seen.contains(&entity)
-                                && !new_seen.contains(&entity)
-                                && dont_log_when_visible.get(entity).is_err()
+    recently_lost.retain(|_entity, timer| !timer.finished());
+    for event in events.iter() {
+        if let Some((viewer_collider, other)) =
+            target_and_other(event.collider1.entity(), event.collider2.entity(), |v| {
+                viewer_colliders.get(v).is_ok()
+            })
+        {
+            if let Ok((viewed_entity, name, rigid_body_position, collider_position)) =
+                viewed.get(other)
+            {
+                if event.intersecting {
+                    if recently_lost.contains_key(&viewed_entity) {
+                        recently_lost.remove(&viewed_entity);
+                    } else {
+                        if let Ok(parent) = viewer_colliders.get(viewer_collider) {
+                            if let Ok((viewer_entity, coordinates, transform)) =
+                                viewers.get(**parent)
                             {
-                                let name = name.to_string();
-                                let forward = transform.local_x();
-                                let yaw = Angle::Radians(forward.y.atan2(forward.x));
-                                let location = coordinates
-                                    .direction_and_distance(viewed_coordinates, Some(yaw));
-                                log.push(format!("{}: {}", name, location));
+                                if viewer_entity == viewed_entity {
+                                    continue;
+                                }
+                                if let Ok(mut log) = log.single_mut() {
+                                    let viewed_coordinates = if let Some(p) = rigid_body_position {
+                                        (p.position.translation.x, p.position.translation.y)
+                                    } else if let Some(p) = collider_position {
+                                        (p.translation.x, p.translation.y)
+                                    } else {
+                                        (0., 0.)
+                                    };
+                                    let forward = transform.local_x();
+                                    let yaw = Angle::Radians(forward.y.atan2(forward.x));
+                                    let location = coordinates
+                                        .direction_and_distance(&viewed_coordinates, Some(yaw));
+                                    log.push(format!("{}: {}", **name, location));
+                                }
                             }
-                            new_seen.insert(entity);
                         }
-                        true
-                    },
-                );
+                    }
+                } else {
+                    recently_lost.insert(viewed_entity, Timer::from_seconds(2., false));
+                }
             }
         }
     }
-    let recently_lost_entities = seen.difference(&new_seen);
-    for entity in recently_lost_entities {
-        recently_lost.insert(*entity, Timer::from_seconds(2., false));
-    }
-    *seen = new_seen;
 }
 
 pub const LOG_VISIBLE_LABEL: &str = "LOG_VISIBLE";
@@ -327,17 +484,20 @@ pub struct VisibilityPlugin;
 
 impl Plugin for VisibilityPlugin {
     fn build(&self, app: &mut AppBuilder) {
-        app.add_system(add_visibility_indices.system())
-            .add_system_to_stage(
-                CoreStage::PostUpdate,
-                update_viewshed_for_coordinates.system(),
-            )
-            .add_system_to_stage(CoreStage::PostUpdate, update_viewshed_for_start.system())
+        app.add_event::<VisibilityChanged>()
+            .add_system(add_visibility_indices.system())
+            .add_system(viewshed_added.system())
+            .add_system(viewshed_changed.system())
+            .add_system(lock_rotation.system())
+            .add_system_to_stage(CoreStage::PostUpdate, viewshed_removed.system())
+            .add_system(update_viewshed_for_coordinates.system())
+            .add_system(update_viewshed_for_start.system())
             .add_system_to_stage(CoreStage::PostUpdate, remove_blocks_visibility.system())
             .add_system_to_stage(
                 CoreStage::PostUpdate,
                 update_visible_and_revealed_tiles.system(),
             )
+            .add_system(intersection.system())
             .add_system_to_stage(CoreStage::PostUpdate, log_visible.system());
     }
 }