From b020a45e650a8a805b1d231b8ec4def30e126c20 Mon Sep 17 00:00:00 2001
From: Daniel Gallups <dsgallups@protonmail.com>
Date: Wed, 4 Sep 2024 00:43:52 -0400
Subject: [PATCH] feat: parallelize consuming plugin

---
 src/cell/mouth.rs      |   9 +--
 src/environment/mod.rs |   4 +-
 src/organism/mod.rs    |  62 +++++-----------
 src/organism/plugin.rs | 156 ++++++++++++++++++++++++-----------------
 4 files changed, 115 insertions(+), 116 deletions(-)

diff --git a/src/cell/mouth.rs b/src/cell/mouth.rs
index cc8bcde..74ef16b 100644
--- a/src/cell/mouth.rs
+++ b/src/cell/mouth.rs
@@ -1,6 +1,6 @@
 use bevy::prelude::*;
 
-use crate::{neighbor::VecExt as _, organism::Organism, CellTree, GameState};
+use crate::{neighbor::VecExt as _, organism::Belly, CellTree, GameState};
 
 use super::Food;
 
@@ -19,7 +19,7 @@ fn consume_food(
     mut commands: Commands,
     locations: Res<CellTree>,
     mouths: Query<(&GlobalTransform, &Parent), With<MouthCell>>,
-    mut organisms: Query<&mut Organism>,
+    mut organisms: Query<&mut Belly>,
     food: Query<&Food>,
 ) {
     for (mouth, mouth_parent) in &mouths {
@@ -40,10 +40,7 @@ fn consume_food(
         }
 
         if food_eaten > 0 {
-            organisms
-                .get_mut(mouth_parent.get())
-                .unwrap()
-                .ate_food(food_eaten);
+            organisms.get_mut(mouth_parent.get()).unwrap().0 += food_eaten;
         }
     }
 }
diff --git a/src/environment/mod.rs b/src/environment/mod.rs
index e4a1490..fb9ab89 100644
--- a/src/environment/mod.rs
+++ b/src/environment/mod.rs
@@ -1,7 +1,7 @@
 pub use bevy::prelude::*;
 use mouse_hover::hover_over_organism;
 
-use crate::cell::CellType;
+use crate::{cell::CellType, organism::Belly};
 
 use super::{
     organism::{Organism, OrganismPlugin},
@@ -121,5 +121,5 @@ fn clear_background(mut color: ResMut<ClearColor>) {
 /// Creates the first organism. [`Organism::insert_at`] is used to unify spawning of the organism in the ECS
 /// as well as placing itself in the [`OccupiedLocations`] hashmap.
 fn spawn_first_organism(mut commands: Commands) {
-    Organism::first_organism().insert_at(&mut commands, Vec2::new(10., 10.));
+    Organism::first_organism().insert_at(&mut commands, Vec2::new(10., 10.), Belly(3));
 }
diff --git a/src/organism/mod.rs b/src/organism/mod.rs
index 6973964..c1fe9b3 100644
--- a/src/organism/mod.rs
+++ b/src/organism/mod.rs
@@ -12,6 +12,15 @@ pub use plugin::*;
 mod reproduction;
 use reproduction::*;
 
+#[derive(Component, Clone)]
+pub struct Belly(pub u64);
+
+#[derive(Component)]
+pub struct Age(pub u64);
+
+#[derive(Component)]
+pub struct StarvedAt(pub u64);
+
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum BrainType {
     Predator,
@@ -23,17 +32,12 @@ pub struct Organism {
     genome: Genome,
     brain: Option<BrainType>,
     can_move: bool,
-    belly: u64,
-    /// in millis
-    time_born: u64,
-    offspring: u64,
     /// in millis
-    last_starved: u64,
     can_reproduce_at: u64,
 }
 
 impl Organism {
-    fn new(genome: Genome, belly: u64, time_born: u64) -> Self {
+    fn new(genome: Genome) -> Self {
         let mut has_producer = false;
         let mut has_eye = false;
         let mut has_mover = false;
@@ -69,15 +73,11 @@ impl Organism {
             genome,
             brain: brain_type,
             can_move: has_mover && !has_producer,
-            belly,
-            time_born,
-            offspring: 0,
-            last_starved: 0,
             can_reproduce_at,
         }
     }
-    pub fn ready_to_reproduce(&self) -> bool {
-        self.belly >= self.can_reproduce_at
+    pub fn ready_to_reproduce(&self, belly: &Belly) -> bool {
+        belly.0 >= self.can_reproduce_at
     }
 
     /// returns the number of cells this organism takes up based on its genome
@@ -102,47 +102,20 @@ impl Organism {
         self.can_move
     }
 
-    pub fn reproduce(&mut self, current_tick: u64) -> Option<Organism> {
-        //always lose half of one's belly
-        self.belly /= 2;
+    pub fn reproduce(&self) -> Option<Organism> {
         let child_genome = self.genome.reproduce();
         if child_genome.num_cells() < 2 {
             return None;
         }
-        self.offspring += 1;
-        Some(Self::new(child_genome, self.belly, current_tick))
+        Some(Self::new(child_genome))
     }
 
     pub fn first_organism() -> Self {
-        Self::new(Genome::first_organism(), 3, 0)
-    }
-    pub fn ate_food(&mut self, amt: u64) {
-        if self.belly < self.can_reproduce_at {
-            self.belly += amt;
-        }
-    }
-
-    pub fn lost_food(&mut self, amt: u64, time: u64) {
-        self.belly = self.belly.saturating_sub(amt);
-        self.last_starved = time;
-        //info!("Organism lost food, belly is at {}", self.belly)
-    }
-
-    /// returns the millisecond last starved
-    pub fn time_last_starved(&self) -> u64 {
-        self.last_starved
-    }
-
-    pub fn time_born(&self) -> u64 {
-        self.time_born
-    }
-
-    pub fn belly(&self) -> u64 {
-        self.belly
+        Self::new(Genome::first_organism())
     }
 
     /// Uses both the ECS and the global positioning hashmap to insert itself.
-    pub fn insert_at(self, commands: &mut Commands, location: impl VecExt) {
+    pub fn insert_at(self, commands: &mut Commands, location: impl VecExt, belly: Belly) {
         /*info!(
             "\nInserting Organism into the world:\nLocation: {:?}\nto insert:{:#?}",
             global_location, self
@@ -157,6 +130,9 @@ impl Organism {
                     ..Default::default()
                 },
                 self,
+                belly,
+                Age(0),
+                StarvedAt(0),
             ))
             .with_children(|child_builder| {
                 genome.spawn_cells(child_builder);
diff --git a/src/organism/plugin.rs b/src/organism/plugin.rs
index b3548fd..88c2a4d 100644
--- a/src/organism/plugin.rs
+++ b/src/organism/plugin.rs
@@ -8,7 +8,7 @@ use crate::{
     CellTree, GameState,
 };
 
-use super::Organism;
+use super::{Age, Belly, Organism, StarvedAt};
 
 /// Combines the systems of cells and organism actions
 pub struct OrganismPlugin;
@@ -27,6 +27,8 @@ impl Plugin for OrganismPlugin {
             .add_systems(
                 Update,
                 (
+                    age_organism.run_if(in_state(GameState::Playing)),
+                    organism_hunger.run_if(in_state(GameState::Playing)),
                     starve_organism.run_if(in_state(GameState::Playing)),
                     reproduce_organism.run_if(in_state(GameState::Playing)),
                 ),
@@ -34,44 +36,62 @@ impl Plugin for OrganismPlugin {
     }
 }
 
-fn starve_organism(
+fn age_organism(time: Res<Time>, mut ages: Query<&mut Age>) {
+    ages.par_iter_mut().for_each(|mut age| {
+        age.0 += time.delta().as_millis() as u64;
+    })
+}
+
+fn organism_hunger(
     time: Res<Time>,
-    mut commands: Commands,
     settings: Res<EnvironmentSettings>,
-    mut organisms: Query<(Entity, &Children, &mut Organism)>,
-    locations: Query<&GlobalTransform>,
+    mut organisms: Query<(&mut Belly, &Age, &mut StarvedAt), With<Organism>>,
 ) {
-    for (organism_entity, children, mut organism) in &mut organisms {
-        let current_time = time.elapsed().as_millis() as u64;
-        let time_alive = current_time - organism.time_born();
-
-        let d_time_last_starved = current_time - organism.time_last_starved();
-        if d_time_last_starved >= settings.hunger_tick {
-            // based on the age of the organism, we out how much food it should lose
-            let age_cost = (time_alive / settings.age_rate) + 1;
-            organism.lost_food(age_cost, current_time);
-        }
-
-        if organism.belly() == 0 {
-            //before the organism dies, we need to turn the children
-            //into food :D
-            // because it could be killed in the meantime or whatnot, we should just lay down the food here
-            for child in children.iter() {
-                let location = locations.get(*child).unwrap();
-                commands.spawn(FoodBundle::at(location.translation()));
+    organisms
+        .par_iter_mut()
+        .for_each(|(mut belly, age, mut organism_starved_at)| {
+            let current_time = time.elapsed().as_millis() as u64;
+
+            let d_time_last_starved = current_time - organism_starved_at.0;
+            if d_time_last_starved >= settings.hunger_tick {
+                // based on the age of the organism, we out how much food it should lose
+                let age_cost = (age.0 / settings.age_rate) + 1;
+                belly.0 = belly.0.saturating_sub(age_cost);
+                organism_starved_at.0 = current_time;
             }
+        });
+}
 
-            commands.entity(organism_entity).despawn_recursive();
-        }
-    }
+fn starve_organism(
+    par_commands: ParallelCommands,
+    organisms: Query<(Entity, &Children, &Belly), With<Organism>>,
+    locations: Query<&GlobalTransform>,
+) {
+    organisms
+        .par_iter()
+        .for_each(|(organism_entity, children, belly)| {
+            if belly.0 == 0 {
+                //before the organism dies, we need to turn the children
+                //into food :D
+                // because it could be killed in the meantime or whatnot, we should just lay down the food here
+
+                par_commands.command_scope(|mut commands| {
+                    for child in children.iter() {
+                        let location = locations.get(*child).unwrap();
+                        commands.spawn(FoodBundle::at(location.translation()));
+                    }
+
+                    commands.entity(organism_entity).despawn_recursive();
+                });
+            }
+        })
 }
 
 fn reproduce_organism(
-    time: Res<Time>,
-    mut commands: Commands,
+    par_commands: ParallelCommands,
     settings: Res<EnvironmentSettings>,
     tree: Res<CellTree>,
-    mut organisms: Query<(&GlobalTransform, &mut Organism)>,
+    mut organisms: Query<(&GlobalTransform, &mut Belly, &Organism)>,
 ) {
     if settings
         .max_organisms
@@ -79,44 +99,50 @@ fn reproduce_organism(
     {
         return;
     }
-
-    for (organism_transform, mut organism) in &mut organisms {
-        if organism.ready_to_reproduce() {
-            let Some(new_organism) = organism.reproduce(time.elapsed().as_millis() as u64) else {
-                continue;
-            };
-
-            let organism_location = organism_transform.translation();
-
-            //info!("the organism has created a child!");
-            //the organism gets three chances to place within the radius of the parent.
-            //otherwise, it dies.
-            let mut chance = 0;
-            let new_organism_location = 'find: loop {
-                if chance > 3 {
-                    break None;
-                }
-                let random_location = organism_location.rand_around(settings.spawn_radius);
-
-                // must spawn 3 blocks away from anything
-                // todo(dsgallups); hack
-                for (_, e) in tree.within_distance(random_location, organism.radius() as f32 + 1.) {
-                    if e.is_some() {
-                        chance += 1;
-                        continue 'find;
+    organisms
+        .par_iter_mut()
+        .for_each(|(organism_transform, mut belly, organism)| {
+            if organism.ready_to_reproduce(&belly) {
+                belly.0 /= 2;
+                let Some(new_organism) = organism.reproduce() else {
+                    return;
+                };
+
+                let organism_location = organism_transform.translation();
+
+                //info!("the organism has created a child!");
+                //the organism gets three chances to place within the radius of the parent.
+                //otherwise, it dies.
+                let mut chance = 0;
+                let new_organism_location = 'find: loop {
+                    if chance > 3 {
+                        break None;
+                    }
+                    let random_location = organism_location.rand_around(settings.spawn_radius);
+
+                    // must spawn 3 blocks away from anything
+                    // todo(dsgallups); hack
+                    for (_, e) in
+                        tree.within_distance(random_location, organism.radius() as f32 + 1.)
+                    {
+                        if e.is_some() {
+                            chance += 1;
+                            continue 'find;
+                        }
                     }
-                }
 
-                break Some(random_location);
-            };
+                    break Some(random_location);
+                };
 
-            let Some(final_child_location) = new_organism_location else {
-                //tough
-                continue;
-            };
+                let Some(final_child_location) = new_organism_location else {
+                    //tough
+                    return;
+                };
 
-            new_organism.insert_at(&mut commands, final_child_location);
-            //info!("Child spawned!");
-        }
-    }
+                par_commands.command_scope(|mut commands| {
+                    new_organism.insert_at(&mut commands, final_child_location, belly.clone());
+                })
+                //info!("Child spawned!");
+            }
+        });
 }