From 3a9ad932e4557bef59d335144452b6196e639f25 Mon Sep 17 00:00:00 2001
From: Timothy Warren <twarren@nabancard.com>
Date: Thu, 3 Feb 2022 10:17:02 -0500
Subject: [PATCH] Make system dispatching multi-threaded

---
 src/systems.rs                          | 22 ++++++-------
 src/systems/dispatcher.rs               |  8 +++++
 src/systems/dispatcher/multi_thread.rs  | 44 +++++++++++++++++++++++++
 src/systems/dispatcher/single_thread.rs |  1 -
 4 files changed, 63 insertions(+), 12 deletions(-)
 create mode 100644 src/systems/dispatcher/multi_thread.rs

diff --git a/src/systems.rs b/src/systems.rs
index cd86105..dc437d3 100644
--- a/src/systems.rs
+++ b/src/systems.rs
@@ -15,17 +15,17 @@ mod trigger_system;
 mod visibility_system;
 
 // System imports
-pub use ai::*;
-pub use hunger_system::HungerSystem;
-pub use inventory_system::*;
-pub use lighting_system::LightingSystem;
-pub use map_indexing_system::MapIndexingSystem;
-pub use melee_combat_system::MeleeCombatSystem;
-pub use movement_system::MovementSystem;
-pub use particle_system::ParticleSpawnSystem;
-pub use ranged_combat_system::RangedCombatSystem;
-pub use trigger_system::TriggerSystem;
-pub use visibility_system::VisibilitySystem;
+use ai::*;
+use hunger_system::HungerSystem;
+use inventory_system::*;
+use lighting_system::LightingSystem;
+use map_indexing_system::MapIndexingSystem;
+use melee_combat_system::MeleeCombatSystem;
+use movement_system::MovementSystem;
+use particle_system::ParticleSpawnSystem;
+use ranged_combat_system::RangedCombatSystem;
+use trigger_system::TriggerSystem;
+use visibility_system::VisibilitySystem;
 
 pub fn build() -> Box<dyn UnifiedDispatcher + 'static> {
     dispatcher::new()
diff --git a/src/systems/dispatcher.rs b/src/systems/dispatcher.rs
index 1120a90..acbef55 100644
--- a/src/systems/dispatcher.rs
+++ b/src/systems/dispatcher.rs
@@ -1,7 +1,15 @@
+#[cfg(target_arch = "wasm32")]
 #[macro_use]
 mod single_thread;
 
+#[cfg(not(target_arch = "wasm32"))]
+#[macro_use]
+mod multi_thread;
+
 use ::specs::prelude::World;
+#[cfg(not(target_arch = "wasm32"))]
+pub use multi_thread::*;
+#[cfg(target_arch = "wasm32")]
 pub use single_thread::*;
 
 use super::*;
diff --git a/src/systems/dispatcher/multi_thread.rs b/src/systems/dispatcher/multi_thread.rs
new file mode 100644
index 0000000..0fc5e42
--- /dev/null
+++ b/src/systems/dispatcher/multi_thread.rs
@@ -0,0 +1,44 @@
+use ::specs::prelude::*;
+
+use super::UnifiedDispatcher;
+
+macro_rules! construct_dispatcher {
+    (
+        $(
+            (
+                $type:ident,
+                $name:expr,
+                $deps:expr
+            )
+        ),*
+    ) => {
+        fn new_dispatch() -> Box<dyn UnifiedDispatcher + 'static> {
+            use ::specs::DispatcherBuilder;
+
+            let dispatcher = DispatcherBuilder::new()
+                $(
+                    .with($type{}, $name, $deps)
+                )*
+                .build();
+
+            let dispatch = MultiThreadedDispatcher {
+                dispatcher: dispatcher
+            };
+
+            return Box::new(dispatch);
+        }
+    };
+}
+
+pub struct MultiThreadedDispatcher {
+    pub dispatcher: ::specs::Dispatcher<'static, 'static>,
+}
+
+impl<'a> UnifiedDispatcher for MultiThreadedDispatcher {
+    fn run_now(&mut self, ecs: *mut World) {
+        unsafe {
+            self.dispatcher.dispatch(&mut *ecs);
+            crate::effects::run_effects_queue(&mut *ecs);
+        }
+    }
+}
diff --git a/src/systems/dispatcher/single_thread.rs b/src/systems/dispatcher/single_thread.rs
index da4247d..9dfdac2 100644
--- a/src/systems/dispatcher/single_thread.rs
+++ b/src/systems/dispatcher/single_thread.rs
@@ -1,6 +1,5 @@
 use ::specs::prelude::*;
 
-use super::super::*;
 use super::UnifiedDispatcher;
 
 macro_rules! construct_dispatcher {