From 86aa2c77be05f282d8e0ea260b999ad089f8107f Mon Sep 17 00:00:00 2001
From: Elias Stepanik <eliasstepanik@proton.me>
Date: Fri, 4 Apr 2025 12:38:29 +0200
Subject: [PATCH] Basic Synced Object Test

---
 client/Cargo.toml                             |  3 +-
 client/src/app.rs                             |  2 +-
 .../plugins/camera/systems/camera_system.rs   | 22 ++++-
 .../plugins/environment/environment_plugin.rs |  3 +-
 .../environment/systems/environment_system.rs | 86 ++++++++++++++++++-
 client/src/plugins/network/mod.rs             |  2 +-
 client/src/plugins/network/network_plugin.rs  |  2 +-
 .../src/plugins/network/systems/database.rs   |  8 +-
 server/Cargo.toml                             |  2 +-
 server/src/lib.rs                             |  9 ++
 server/src/types/entity.rs                    | 27 ++++++
 server/src/types/mod.rs                       |  3 +-
 server/src/types/player.rs                    |  1 +
 server/src/types/vec3.rs                      | 12 ---
 14 files changed, 154 insertions(+), 28 deletions(-)
 create mode 100644 server/src/types/entity.rs

diff --git a/client/Cargo.toml b/client/Cargo.toml
index cece379..ed77906 100644
--- a/client/Cargo.toml
+++ b/client/Cargo.toml
@@ -18,4 +18,5 @@ bevy_window = "0.15.0"
 egui_dock = "0.14.0"
 spacetimedb-sdk = "1.0"
 hex = "0.4"
-random_word = { version = "0.5.0", features = ["en"] }
\ No newline at end of file
+random_word = { version = "0.5.0", features = ["en"] }
+rand = "0.8.5"
\ No newline at end of file
diff --git a/client/src/app.rs b/client/src/app.rs
index 149e815..5542051 100644
--- a/client/src/app.rs
+++ b/client/src/app.rs
@@ -28,7 +28,7 @@ impl Plugin for AppPlugin {
         app.add_plugins(crate::plugins::camera::camera_plugin::CameraPlugin);
         app.add_plugins(crate::plugins::ui::ui_plugin::UiPlugin);
         app.add_plugins(crate::plugins::environment::environment_plugin::EnvironmentPlugin);
-        app.add_systems(Startup, setup_database);
+        app.add_plugins(crate::plugins::network::network_plugin::NetworkPlugin);
 
 
         app.add_systems(Update, (debug_gizmos, toggle_ui_system));
diff --git a/client/src/plugins/camera/systems/camera_system.rs b/client/src/plugins/camera/systems/camera_system.rs
index 04ac0f5..24aa07f 100644
--- a/client/src/plugins/camera/systems/camera_system.rs
+++ b/client/src/plugins/camera/systems/camera_system.rs
@@ -4,8 +4,9 @@ use bevy::math::Vec3;
 use bevy::prelude::*;
 use bevy_render::camera::{Exposure, PhysicalCameraParameters, Projection};
 use bevy_window::CursorGrabMode;
+use rand::Rng;
 use random_word::Lang;
-use crate::module_bindings::set_name;
+use crate::module_bindings::{set_name, spawn_entity, DbVector3};
 use crate::plugins::network::systems::database::DbConnectionResource;
 
 #[derive(Component)]
@@ -47,6 +48,15 @@ pub fn setup(mut commands: Commands) {
     ));
 }
 
+fn random_vec3(min: f32, max: f32) -> Vec3 {
+    let mut rng = rand::thread_rng();
+    Vec3::new(
+        rng.gen_range(min..max),
+        rng.gen_range(min..max),
+        rng.gen_range(min..max),
+    )
+}
+
 /// Example system to control a camera using double-precision for position.
 pub fn camera_controller_system(
     time: Res<Time>,
@@ -98,9 +108,17 @@ pub fn camera_controller_system(
 
     let word = random_word::get(Lang::En);
 
-    if keyboard_input.just_pressed(KeyCode::KeyQ) {
+    if keyboard_input.just_pressed(KeyCode::Numpad1) {
         ctx.0.reducers.set_name(word.to_string()).unwrap();
     }
+    if keyboard_input.just_pressed(KeyCode::Numpad2) {
+        let rand_position = random_vec3(-10.0,10.0);
+        ctx.0.reducers.spawn_entity(DbVector3{
+            x: rand_position.x,
+            y: rand_position.y,
+            z: rand_position.z,
+        }).unwrap();
+    }
 
     // ====================
     // 3) Handle Keyboard Movement (WASD, Space, Shift)
diff --git a/client/src/plugins/environment/environment_plugin.rs b/client/src/plugins/environment/environment_plugin.rs
index 3bd2a9f..c3a0b34 100644
--- a/client/src/plugins/environment/environment_plugin.rs
+++ b/client/src/plugins/environment/environment_plugin.rs
@@ -7,7 +7,6 @@ pub struct EnvironmentPlugin;
 impl Plugin for EnvironmentPlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(Startup, init);
-        app.add_systems(FixedUpdate, fixed_update);
-        app.add_systems(Update, fixed_update);
+        app.add_systems(Update, sync_entities_system);
     }
 }
diff --git a/client/src/plugins/environment/systems/environment_system.rs b/client/src/plugins/environment/systems/environment_system.rs
index 5fcf3b5..a99b6b8 100644
--- a/client/src/plugins/environment/systems/environment_system.rs
+++ b/client/src/plugins/environment/systems/environment_system.rs
@@ -1,13 +1,93 @@
 
 use bevy::prelude::*;
+use spacetimedb_sdk::Table;
+use crate::module_bindings::{entity_table, DbVector3, EntityTableAccess};
+use crate::plugins::network::systems::database::DbConnectionResource;
 
+#[derive(Component)]
+pub struct EntityDto {
 
-
-pub fn init(mut commands: Commands) {
+    pub entity_id: u32,
+    pub position: DbVector3,
 }
 
-pub fn fixed_update(time: Res<Time>,) {                
+pub fn init(mut commands: Commands,
+            ctx: Res<DbConnectionResource>,
+            mut meshes: ResMut<Assets<Mesh>>,
+            mut materials: ResMut<Assets<StandardMaterial>>,) {
 
+
+
+    let debug_material = materials.add(StandardMaterial { ..default() });
+
+    for entity in ctx.0.db.entity().iter() {
+        commands.spawn((
+            Mesh3d(meshes.add(Cuboid::default()),),
+            MeshMaterial3d(debug_material.clone ()),
+            Transform::from_xyz(
+                entity.position.x,
+                entity.position.y,
+                entity.position.z,
+            ),
+            EntityDto{
+                entity_id: entity.entity_id,
+                position: entity.position,
+            }
+        ));
+
+    }
+
+
+}
+
+
+
+pub fn sync_entities_system(
+    mut commands: Commands,
+    db_resource: Res<DbConnectionResource>,
+    mut query: Query<(Entity, &mut Transform, &mut EntityDto)>,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+) {
+    let ctx = &db_resource.0.db;
+
+    // For each entity record in DB, see if it exists in ECS:
+    for db_entity in ctx.entity().iter() {
+        // Try to find a matching entity in ECS by comparing `entity_id`
+        if let Some((entity, mut transform, mut dto)) = query
+            .iter_mut()
+            .find(|(_, _, dto)| dto.entity_id == db_entity.entity_id)
+        {
+            // It already exists. Perhaps update ECS data to match DB:
+            dto.position = db_entity.position;
+            transform.translation = Vec3::new(
+                dto.position.x,
+                dto.position.y,
+                dto.position.z,
+            );
+            // ...do any other sync logic
+        } else {
+
+
+            let debug_material = materials.add(StandardMaterial { ..default() });
+            // Not found in ECS, so spawn a new entity
+            commands.spawn((
+                EntityDto {
+                    entity_id: db_entity.entity_id,
+                    position: db_entity.position.clone(),
+                },
+                // Create an initial transform using DB data
+                Transform::from_xyz(
+                    db_entity.position.x,
+                    db_entity.position.y,
+                    db_entity.position.z,
+                ),
+                GlobalTransform::default(),
+                Mesh3d(meshes.add(Cuboid::default()),),
+                MeshMaterial3d(debug_material.clone ()),
+            ));
+        }
+    }
 }
 
 pub fn update(time: Res<Time>,)  {
diff --git a/client/src/plugins/network/mod.rs b/client/src/plugins/network/mod.rs
index a58959e..3f3f609 100644
--- a/client/src/plugins/network/mod.rs
+++ b/client/src/plugins/network/mod.rs
@@ -1,2 +1,2 @@
 pub(crate) mod systems;
-mod network_plugin;
\ No newline at end of file
+pub mod network_plugin;
\ No newline at end of file
diff --git a/client/src/plugins/network/network_plugin.rs b/client/src/plugins/network/network_plugin.rs
index 274e8c9..d5eb8f3 100644
--- a/client/src/plugins/network/network_plugin.rs
+++ b/client/src/plugins/network/network_plugin.rs
@@ -8,6 +8,6 @@ use crate::plugins::network::systems::database::setup_database;
 pub struct NetworkPlugin;
 impl Plugin for NetworkPlugin {
     fn build(&self, app: &mut App) {
-        app.add_systems(Startup, setup_database);
+        app.add_systems(PreStartup, setup_database);
     }
 }
diff --git a/client/src/plugins/network/systems/database.rs b/client/src/plugins/network/systems/database.rs
index fc98dfb..8956754 100644
--- a/client/src/plugins/network/systems/database.rs
+++ b/client/src/plugins/network/systems/database.rs
@@ -1,5 +1,5 @@
-
-use bevy::prelude::{Commands, Resource};
+use bevy::ecs::system::SystemState;
+use bevy::prelude::{Commands, Resource, World};
 use bevy::utils::info;
 use spacetimedb_sdk::{credentials, DbContext, Error, Event, Identity, Status, Table, TableWithPrimaryKey};
 use crate::module_bindings::*;
@@ -23,6 +23,8 @@ pub fn setup_database(mut commands: Commands) {
     subscribe_to_tables(&ctx);
     ctx.run_threaded();
     commands.insert_resource(DbConnectionResource(ctx));
+    
+
 }
 
 
@@ -57,5 +59,5 @@ fn subscribe_to_tables(ctx: &DbConnection) {
     ctx.subscription_builder()
         .on_applied(on_sub_applied)
         .on_error(on_sub_error)
-        .subscribe(["SELECT * FROM player"]);
+        .subscribe(["SELECT * FROM player", "SELECT * FROM entity"]);
 }
\ No newline at end of file
diff --git a/server/Cargo.toml b/server/Cargo.toml
index 3860cdf..73d2a1a 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -10,4 +10,4 @@ crate-type = ["cdylib"]
 
 [dependencies]
 spacetimedb = "1.0.1"
-log = "0.4"
+log = "0.4"
\ No newline at end of file
diff --git a/server/src/lib.rs b/server/src/lib.rs
index e4ef524..fbbca0e 100644
--- a/server/src/lib.rs
+++ b/server/src/lib.rs
@@ -44,4 +44,13 @@ pub fn identity_disconnected(ctx: &ReducerContext) {
         // as it doesn't make sense for a client to disconnect without connecting first.
         log::warn!("Disconnect event for unknown Player with identity {:?}", ctx.sender);
     }
+}
+
+#[spacetimedb::reducer(init)]
+pub fn init(ctx: &ReducerContext) -> Result<(), String> {
+    log::info!("Initializing...");
+    ctx.db.config().try_insert(Config {
+        id: 0,
+    })?;
+    Ok(())
 }
\ No newline at end of file
diff --git a/server/src/types/entity.rs b/server/src/types/entity.rs
new file mode 100644
index 0000000..8f4ac51
--- /dev/null
+++ b/server/src/types/entity.rs
@@ -0,0 +1,27 @@
+
+use spacetimedb::{Identity, ReducerContext, Table};
+use crate::types::vec3::{DbVector3};
+
+#[spacetimedb::table(name = entity, public)]
+#[derive(Debug, Clone, )]
+pub struct Entity {
+    #[auto_inc]
+    #[primary_key]
+    pub entity_id: u32,
+
+
+    pub position: DbVector3,
+
+}
+
+#[spacetimedb::reducer]
+pub fn spawn_entity(ctx: &ReducerContext, position: DbVector3) -> Result<(), String> {
+
+    ctx.db.entity().try_insert(Entity {
+        entity_id: 0,
+        position,
+    }).expect("TODO: panic message");
+
+
+    Ok(())
+}
\ No newline at end of file
diff --git a/server/src/types/mod.rs b/server/src/types/mod.rs
index f6ac828..5ca9fc7 100644
--- a/server/src/types/mod.rs
+++ b/server/src/types/mod.rs
@@ -1,2 +1,3 @@
 pub mod vec3;
-pub mod player;
\ No newline at end of file
+pub mod player;
+mod entity;
\ No newline at end of file
diff --git a/server/src/types/player.rs b/server/src/types/player.rs
index 3565a95..735ae6a 100644
--- a/server/src/types/player.rs
+++ b/server/src/types/player.rs
@@ -29,3 +29,4 @@ fn validate_name(name: String) -> Result<String, String> {
         Ok(name)
     }
 }
+
diff --git a/server/src/types/vec3.rs b/server/src/types/vec3.rs
index d80369d..0f75fd1 100644
--- a/server/src/types/vec3.rs
+++ b/server/src/types/vec3.rs
@@ -5,16 +5,4 @@ pub struct DbVector3 {
     pub x: f32,
     pub y: f32,
     pub z: f32,
-}
-
-#[spacetimedb::table(name = entity, public)]
-#[derive(Debug, Clone)]
-pub struct Entity {
-    // The `auto_inc` attribute indicates to SpacetimeDB that
-    // this value should be determined by SpacetimeDB on insert.
-    #[auto_inc]
-    #[primary_key]
-    pub entity_id: u32,
-    pub position: DbVector3,
-    pub mass: u32,
 }
\ No newline at end of file