From f78d4c7f4042d9753f97e6cc19b6eb470f673f4c Mon Sep 17 00:00:00 2001
From: Franklin <franklinblanco@tutanota.com>
Date: Sat, 25 Nov 2023 14:39:02 -0400
Subject: [PATCH]  EventCollision system that takes into account more than one
 type of collider AND Auto Low ready when gun collider hits object OR when
 player starts sprinting

---
 Design.md                                     |  8 +-
 src/comps/core/events/bullet_collision.rs     | 11 +++
 src/comps/core/events/collision_event_type.rs |  6 ++
 .../core/events/equipped_gun_collision.rs     | 10 +++
 src/comps/core/events/mod.rs                  |  3 +
 .../markers/proxy/weapons/gun_colliders.rs    | 14 +--
 src/logic/core/collisions.rs                  | 87 +++++++++++++++++++
 src/logic/core/guns/despawn_shots.rs          | 80 +++++++----------
 .../core/guns/equipped_gun_collisions.rs      | 27 ++++++
 src/logic/core/guns/mod.rs                    |  3 +-
 src/logic/core/guns/player_firing.rs          |  4 +
 src/logic/core/mod.rs                         |  1 +
 src/logic/core/player/hands.rs                |  3 +-
 src/scenes/scene1/init.rs                     | 10 ++-
 14 files changed, 202 insertions(+), 65 deletions(-)
 create mode 100644 src/comps/core/events/bullet_collision.rs
 create mode 100644 src/comps/core/events/collision_event_type.rs
 create mode 100644 src/comps/core/events/equipped_gun_collision.rs
 create mode 100644 src/logic/core/collisions.rs
 create mode 100644 src/logic/core/guns/equipped_gun_collisions.rs

diff --git a/Design.md b/Design.md
index 1a3da2f..2c29815 100644
--- a/Design.md
+++ b/Design.md
@@ -31,14 +31,18 @@ Multiplayer
 - [x] High Ready & Low Ready system with state
     - [x] High ready animation (procedural)
     - [x] Low ready animation (procedural)
-    - [ ] TODO: Auto Low ready when gun collider hits object OR when player starts sprinting
+- [x] EventCollision system that takes into account more than one type of collider.
+    - [x] Auto Low ready when gun collider hits object OR when player starts sprinting
+    - [ ] (Not a priority) Collision with wall and attempting to Aim can look very twitchy, maybe add a cooldown of 0.1-0.4s on each change from low ready to high ready
+- [ ] Optics
+    - [ ] All optics implementing a fn/trait that gives a specific gun offset to use the optic correctly
+    - [ ] Find some way to implement a shader for the optics
 - [ ] Bobbing
     - [ ] Gun Bob on run
     - [ ] Gun Bob on walk
 - [ ] Reload animation (procedural)
     - [ ] Real world magazines
 - [ ] Rewriting bullet physics to use raycasts & kinematic rigidbodies (logic controlled)
-    
 - [ ] Create a Controls struct that holds mappings to all the game keys and replace them in all the game's code
 
 
diff --git a/src/comps/core/events/bullet_collision.rs b/src/comps/core/events/bullet_collision.rs
new file mode 100644
index 0000000..77f9e2d
--- /dev/null
+++ b/src/comps/core/events/bullet_collision.rs
@@ -0,0 +1,11 @@
+use bevy::{ecs::{event::Event, entity::Entity}, transform::components::Transform};
+
+use super::collision_event_type::CollisionEventType;
+
+#[derive(Event)]
+pub struct BulletCollisionEvent {
+    pub bullet: Entity,
+    pub other: Entity,
+    pub at: Transform,
+    pub collision_type: CollisionEventType,
+}
\ No newline at end of file
diff --git a/src/comps/core/events/collision_event_type.rs b/src/comps/core/events/collision_event_type.rs
new file mode 100644
index 0000000..37980bc
--- /dev/null
+++ b/src/comps/core/events/collision_event_type.rs
@@ -0,0 +1,6 @@
+
+#[derive(PartialEq, Copy, Clone)]
+pub enum CollisionEventType {
+    Start,
+    End,
+}
\ No newline at end of file
diff --git a/src/comps/core/events/equipped_gun_collision.rs b/src/comps/core/events/equipped_gun_collision.rs
new file mode 100644
index 0000000..45362ca
--- /dev/null
+++ b/src/comps/core/events/equipped_gun_collision.rs
@@ -0,0 +1,10 @@
+use bevy::ecs::{event::Event, entity::Entity};
+
+use super::collision_event_type::CollisionEventType;
+
+#[derive(Event)]
+pub struct EquippedGunCollisionEvent {
+    pub gun: Entity,
+    pub other: Entity,
+    pub collision_type: CollisionEventType,
+}
\ No newline at end of file
diff --git a/src/comps/core/events/mod.rs b/src/comps/core/events/mod.rs
index aa3a379..a157e27 100644
--- a/src/comps/core/events/mod.rs
+++ b/src/comps/core/events/mod.rs
@@ -1,3 +1,6 @@
 //pub mod loot_container;
 pub mod inventory_changed;
 pub mod pickup_item;
+pub mod bullet_collision;
+pub mod equipped_gun_collision;
+pub mod collision_event_type;
\ No newline at end of file
diff --git a/src/comps/core/markers/proxy/weapons/gun_colliders.rs b/src/comps/core/markers/proxy/weapons/gun_colliders.rs
index 4d281ca..c022a28 100644
--- a/src/comps/core/markers/proxy/weapons/gun_colliders.rs
+++ b/src/comps/core/markers/proxy/weapons/gun_colliders.rs
@@ -1,5 +1,5 @@
 use bevy::prelude::*;
-use bevy_rapier3d::geometry::Sensor;
+use bevy_rapier3d::geometry::{Sensor, ActiveEvents};
 
 use crate::{comps::core::markers::holdable::InPlayerHands, utils::hierarchy::find_child_in_parent_children};
 
@@ -9,14 +9,6 @@ use crate::{comps::core::markers::holdable::InPlayerHands, utils::hierarchy::fin
 #[reflect(Component)]
 pub struct GunFirearmCollider;
 
-
-/*for (gun_firearm_collider_entity, _) in gun_firearm_collider_query.iter() {
-                println!("a");
-                if find_child_in_parent_children(commands, firearm_asset_entity, gun_firearm_collider_entity, &children) {
-                    println!("Sensor");
-                    commands.entity(gun_firearm_collider_entity).insert(Sensor);
-                }
-            } */
 pub fn update_gun_collider(
     mut commands: Commands,
     gun_firearm_collider_query: Query<Entity, Added<GunFirearmCollider>>,
@@ -27,11 +19,11 @@ pub fn update_gun_collider(
         let mut found = false;
         for in_player_hands_entity in in_player_hands_query.iter() {
             if find_child_in_parent_children(&mut commands, in_player_hands_entity, gun_firearm_collider_entity, &children) {
-                commands.entity(gun_firearm_collider_entity).insert(Sensor);
+                commands.entity(gun_firearm_collider_entity).insert(Sensor).insert(ActiveEvents::COLLISION_EVENTS);
                 found = true;
             }
         }
         if found { continue; }
-        commands.entity(gun_firearm_collider_entity).remove::<Sensor>();
+        commands.entity(gun_firearm_collider_entity).remove::<Sensor>().remove::<ActiveEvents>();
     }
 }
\ No newline at end of file
diff --git a/src/logic/core/collisions.rs b/src/logic/core/collisions.rs
new file mode 100644
index 0000000..bdbaea4
--- /dev/null
+++ b/src/logic/core/collisions.rs
@@ -0,0 +1,87 @@
+//!
+//! The goal of this module is to provide collision hydration to all other systems in the game.
+//! The reason is, well, rapier does not give a way to read collisions in multiple systems.
+//! If you read a collision event you automatically starve the systems relying on it. 
+//!
+//! Have Different collision events for different systems, don't call the system directly, just use events to pass in collisions.
+//! 
+
+use bevy::{prelude::*, ecs::system::SystemParam};
+use bevy_rapier3d::{pipeline::CollisionEvent, rapier::geometry::CollisionEventFlags, geometry::Sensor};
+
+use crate::comps::core::{markers::{bullet::BulletMarker, proxy::weapons::gun_colliders::GunFirearmCollider}, events::{bullet_collision::BulletCollisionEvent, equipped_gun_collision::EquippedGunCollisionEvent, collision_event_type::CollisionEventType}};
+
+#[derive(SystemParam)]
+pub struct CollisionHandlerQueryParams<'w, 's> {
+    bullets: Query<'w, 's, (Entity, &'static Transform), With<BulletMarker>>,
+    firearms: Query<'w, 's, Entity, (With<Sensor>, With<GunFirearmCollider>, Without<BulletMarker>)>,
+}
+
+#[derive(SystemParam)]
+pub struct CollisionHandlerEventParams<'w> {
+    bullet_collision_events: EventWriter<'w, BulletCollisionEvent>,
+    equipped_gun_collision_events: EventWriter<'w, EquippedGunCollisionEvent>,
+}
+
+pub fn collision_handler(
+    queries: CollisionHandlerQueryParams,
+    mut events: CollisionHandlerEventParams,
+    mut collisions: EventReader<CollisionEvent>,
+    //time: Res<Time>,
+) {
+    for collision in collisions.read() {
+        let (entity_a, entity_b, flags, collision_type) = match collision {
+            CollisionEvent::Started(entity_a, entity_b, flags) => {
+                (entity_a, entity_b, flags, CollisionEventType::Start)
+            }
+            CollisionEvent::Stopped(entity_a, entity_b, flags) => {
+                (entity_a, entity_b, flags, CollisionEventType::End)
+            }
+        };
+
+        if entity_a == entity_b { continue; } // Avoid inner collisions
+        if flags.contains(CollisionEventFlags::SENSOR) { // Sensor collision event handling
+            println!("Sensor collision");
+            // ######
+            // Equipped Firearm Collisions
+            // ######
+            for gun_collider in queries.firearms.iter() {
+                println!("Gun collider entity detected");
+                if &gun_collider == entity_a {
+                    events.equipped_gun_collision_events.send(EquippedGunCollisionEvent {
+                        gun: gun_collider,
+                        other: *entity_b,
+                        collision_type,
+                    });
+                } else if &gun_collider == entity_b {
+                    events.equipped_gun_collision_events.send(EquippedGunCollisionEvent {
+                        gun: gun_collider,
+                        other: *entity_a,
+                        collision_type,
+                    });
+                }
+            }
+            continue; // Continue, as we already handled sensor collisions
+        }
+        // ######
+        // Bullet collisions
+        // ######
+        for (bullet, bullet_transform) in queries.bullets.iter() {
+            if entity_a == &bullet {
+                events.bullet_collision_events.send(BulletCollisionEvent {
+                    bullet,
+                    other: *entity_b,
+                    at: *bullet_transform,
+                    collision_type,
+                });
+            } else if entity_b == &bullet {
+                events.bullet_collision_events.send(BulletCollisionEvent {
+                    bullet,
+                    other: *entity_a,
+                    at: *bullet_transform,
+                    collision_type,
+                });
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/logic/core/guns/despawn_shots.rs b/src/logic/core/guns/despawn_shots.rs
index f4b5a19..492c636 100644
--- a/src/logic/core/guns/despawn_shots.rs
+++ b/src/logic/core/guns/despawn_shots.rs
@@ -1,6 +1,6 @@
-use crate::comps::core::markers::{bullet::BulletMarker, muzzle_flash::MuzzleFlashMarker};
+use crate::comps::core::{markers::{bullet::BulletMarker, muzzle_flash::MuzzleFlashMarker}, events::{bullet_collision::BulletCollisionEvent, collision_event_type::CollisionEventType}};
 use bevy::prelude::*;
-use bevy_rapier3d::{prelude::*, rapier::geometry::CollisionEventFlags};
+use bevy_rapier3d::prelude::*;
 
 pub fn despawn_muzzle_flashes(
     mut commands: Commands,
@@ -21,59 +21,45 @@ pub fn despawn_stray_bullets(
     mut materials: ResMut<Assets<StandardMaterial>>,
     mut query: Query<(&mut BulletMarker, Entity, &Transform)>,
     
-    mut collisions: EventReader<CollisionEvent>,
-    //res: Res<IntegrationParameters>,
+    mut bullet_collisions: EventReader<BulletCollisionEvent>,
     time: Res<Time>,
 ) {
-    let collisions_read: Vec<&CollisionEvent> = collisions.read().collect();
-    for (mut bullet, bullet_entity, transform) in query.iter_mut() {
-        bullet.timer.tick(time.delta());
-        for event in collisions_read.iter() {
-            match event {
-                CollisionEvent::Started(entity_a, entity_b, flags) => {
-                    if flags.contains(CollisionEventFlags::SENSOR) {
-                        continue;
-                    }
-                    if entity_a == entity_b {
-                        // Avoid inner collisions
-                        continue;
-                    }
-                    if entity_a == &bullet_entity || entity_b == &bullet_entity {
-                        commands.entity(bullet_entity).remove::<Collider>();
-                        //commands.entity(bullet_entity).insert(Sensor);
-                        spawn_bullet_hit_marker(
-                            &mut commands,
-                            transform.translation,
-                            &mut meshes,
-                            &mut materials,
-                        );
-                    }
-                }
-                CollisionEvent::Stopped(entity_a, entity_b, flags) => {
-                    if flags.contains(CollisionEventFlags::SENSOR) {
-                        continue;
-                    }
-                    if entity_a == entity_b {
-                        // Avoid inner collisions
-                        continue;
-                    }
-                    if entity_a == &bullet_entity || entity_b == &bullet_entity {
+    let collisions_read: Vec<&BulletCollisionEvent> = bullet_collisions.read().collect();
+        for event in collisions_read.into_iter() {
+            match event.collision_type {
+                CollisionEventType::Start => {
+                    
+                    commands.entity(event.bullet).remove::<Collider>();
+                    //commands.entity(bullet_entity).insert(Sensor);
+                    spawn_bullet_hit_marker(
+                        &mut commands,
+                        event.at.translation,
+                        &mut meshes,
+                        &mut materials,
+                    );
+                },
+                CollisionEventType::End => {
+                    for (bullet, bullet_entity, _) in query.iter() {
+                        if bullet_entity != event.bullet { continue; }
                         commands
-                            .entity(bullet_entity)
+                            .entity(event.bullet)
                             .insert(Collider::ball(bullet.caliber.size()));
-                        //commands.entity(bullet_entity).remove::<Sensor>();
-                        //commands.entity(*entity_b).despawn();
-                        spawn_bullet_exit_marker(
-                            &mut commands,
-                            transform.translation,
-                            &mut meshes,
-                            &mut materials,
-                        );
-                        continue;
                     }
+                    
+                    //commands.entity(bullet_entity).remove::<Sensor>();
+                    //commands.entity(*entity_b).despawn();
+                    spawn_bullet_exit_marker(
+                        &mut commands,
+                        event.at.translation,
+                        &mut meshes,
+                        &mut materials,
+                    );
+                    continue;
                 } //_ => {}
             }
         }
+    for (mut bullet, bullet_entity, transform) in query.iter_mut() {
+        bullet.timer.tick(time.delta());
         if bullet.timer.finished() {
             commands.entity(bullet_entity).despawn();
         }
diff --git a/src/logic/core/guns/equipped_gun_collisions.rs b/src/logic/core/guns/equipped_gun_collisions.rs
new file mode 100644
index 0000000..dad9027
--- /dev/null
+++ b/src/logic/core/guns/equipped_gun_collisions.rs
@@ -0,0 +1,27 @@
+use bevy::prelude::*;
+
+
+use crate::comps::core::events::{equipped_gun_collision::EquippedGunCollisionEvent, collision_event_type::CollisionEventType};
+
+use super::player_firing::{PlayerFiringInfo, GunReadyPose};
+
+pub fn update_gun_position_on_collision(
+    mut query: Query<&mut PlayerFiringInfo>,
+    mut events: EventReader<EquippedGunCollisionEvent>,
+) {
+    for event in events.read() {
+        println!("Collision");
+        for mut player_firing_info in query.iter_mut() {
+            match event.collision_type {
+                CollisionEventType::Start => {
+                    player_firing_info.gun_ready_pose = GunReadyPose::LowReady;
+                    player_firing_info.gun_colliding_with_object = true;
+                },
+                CollisionEventType::End => {
+                    player_firing_info.gun_colliding_with_object = false;
+                    //player_firing_info.gun_ready_pose = GunReadyPose::HighReady;
+                },
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/logic/core/guns/mod.rs b/src/logic/core/guns/mod.rs
index c9aba0e..9c668ea 100644
--- a/src/logic/core/guns/mod.rs
+++ b/src/logic/core/guns/mod.rs
@@ -1,4 +1,5 @@
 pub mod despawn_shots;
 pub mod player_firing;
 pub mod shoot;
-pub mod inspect;
\ No newline at end of file
+pub mod inspect;
+pub mod equipped_gun_collisions;
\ No newline at end of file
diff --git a/src/logic/core/guns/player_firing.rs b/src/logic/core/guns/player_firing.rs
index c284472..1186278 100644
--- a/src/logic/core/guns/player_firing.rs
+++ b/src/logic/core/guns/player_firing.rs
@@ -24,6 +24,9 @@ pub struct PlayerFiringInfo {
     pub is_reloading: bool,
     pub gun_ready_pose: GunReadyPose,
     pub is_inspecting: bool,
+    /// This is specifically for situations where the player is holding a gun that is stuck against a wall, and should not be false
+    /// until the gun stops colliding with the wall.
+    pub gun_colliding_with_object: bool,
 }
 
 impl Default for PlayerFiringInfo {
@@ -36,6 +39,7 @@ impl Default for PlayerFiringInfo {
             is_reloading: false,
             gun_ready_pose: GunReadyPose::LowReady,
             is_inspecting: false,
+            gun_colliding_with_object: false,
         }
     }
 }
diff --git a/src/logic/core/mod.rs b/src/logic/core/mod.rs
index c305a4a..854fc08 100644
--- a/src/logic/core/mod.rs
+++ b/src/logic/core/mod.rs
@@ -1,2 +1,3 @@
 pub mod guns;
 pub mod player;
+pub mod collisions;
\ No newline at end of file
diff --git a/src/logic/core/player/hands.rs b/src/logic/core/player/hands.rs
index 066dad1..3ad69c6 100644
--- a/src/logic/core/player/hands.rs
+++ b/src/logic/core/player/hands.rs
@@ -144,6 +144,7 @@ pub fn capture_hand_usage(
             } else if !mouse_wheel_events.is_empty() {
                 if player.0.equipment.is_firearm() {
                     for mouse_wheel_event in mouse_wheel_events.read() {
+                        if player_firing_info.gun_colliding_with_object { continue; }
                         if mouse_wheel_event.y >= 0.0 {
                             player_firing_info.gun_ready_pose = GunReadyPose::HighReady;
                         } else {
@@ -196,7 +197,7 @@ pub fn capture_hand_usage(
                                     }
                                 };
                                 if resources.mouse_buttons.pressed(MouseButton::Right)
-                                    && !resources.game_ui_state.any_window() && !player_linear_xz_state.is_sprinting()
+                                    && !resources.game_ui_state.any_window() && !player_linear_xz_state.is_sprinting() && !player_firing_info.gun_colliding_with_object
                                 {
                                     player_firing_info.gun_ready_pose = GunReadyPose::HighReady;
                                     let rotation_lerp_quat = in_hand_transform.rotation.lerp(
diff --git a/src/scenes/scene1/init.rs b/src/scenes/scene1/init.rs
index 9a3d828..6c21884 100644
--- a/src/scenes/scene1/init.rs
+++ b/src/scenes/scene1/init.rs
@@ -4,10 +4,10 @@ use crate::{
     comps::core::{
         controller::capture_input,
         inventory::plugin::InventoryPlugin,
-        spawners::{player::player_spawner, spawn::SpawnerPlugin},
+        spawners::{player::player_spawner, spawn::SpawnerPlugin}, events::{bullet_collision::BulletCollisionEvent, equipped_gun_collision::EquippedGunCollisionEvent},
     },
     logic::core::{
-        guns::{despawn_shots::{despawn_muzzle_flashes, despawn_stray_bullets}, inspect::inspect_firearm},
+        guns::{despawn_shots::{despawn_muzzle_flashes, despawn_stray_bullets}, inspect::inspect_firearm, equipped_gun_collisions::update_gun_position_on_collision},
         player::{
             camera_player_sync::{
                 follow_cursor_with_camera, update_camera_vertical_position, MouseMovementSettings,
@@ -15,7 +15,7 @@ use crate::{
             hands::{capture_hand_usage, interact_action},
             player_values_state::PlayerValuesState,
             player_vertical_sync::sync_player_y_state, camera_switching::switch_camera,
-        },
+        }, collisions::collision_handler,
     },
     setup::{
         //animations::{load_animations, AllAnimations},
@@ -60,9 +60,13 @@ pub fn load_scene(application: &mut App) {
     application.add_systems(Update, change_equipment.before(player_spawner));
     application.add_systems(Update, (despawn_muzzle_flashes, despawn_stray_bullets));
     application.add_systems(Update, inspect_firearm);
+    application.add_systems(Update, collision_handler);
+    application.add_systems(Update, update_gun_position_on_collision);
 
     //application.add_systems(Update, animate_player);
     //application.add_systems(Update, register_bullet_hits);
 
     application.add_event::<EquipmentChangeEvent>();
+    application.add_event::<BulletCollisionEvent>();
+    application.add_event::<EquippedGunCollisionEvent>();
 }