scripting: implement spawning entity with loaded 3d models

examples/testbed/scripts/test.lua

@@ -1,10 +1,12 @@
---local cube: resource = world:request_res("loader", "assets/cube-texture-embedded.gltf")
-
---cube = nil
-
 function on_init()
     local cube = world:request_res("assets/cube-texture-embedded.gltf")
     print("Loaded textured cube")
+
+    local pos = Transform.from_translation(Vec3.new(0, 0, -8.0))
+    local cube_comp = ModelComponent.new(cube)
+
+    local e = world:spawn(pos, cube_comp)
+    print("spawned entity " .. tostring(e))
 end
 
 --[[ function on_first()

lyra-ecs/src/system/fn_sys.rs

@@ -80,12 +80,13 @@ macro_rules! impl_fn_system_tuple {
 
             fn execute_deferred(&mut self, world: NonNull<World>) -> anyhow::Result<()> {
                 let state = self.arg_state.as_mut().expect("Somehow there was no state");
+                state.reverse();
 
                 $(
                     let arg_state_box = state.pop()
                         .expect("Missing expected arg state");
                     let arg_state = *arg_state_box.downcast::<$name::State>()
-                        .unwrap();
+                        .expect("Somehow the state cannot be downcasted from boxed Any");
                     $name::apply_deferred(arg_state, world);
                 )+
 

lyra-ecs/src/system/graph.rs

@@ -2,7 +2,7 @@ use std::{collections::{HashMap, VecDeque, HashSet}, ptr::NonNull};
 
 use super::System;
 
-use crate::world::World;
+use crate::{world::World, CommandQueue, Commands};
 
 #[derive(thiserror::Error, Debug)]
 pub enum GraphExecutorError {
@@ -58,7 +58,7 @@ impl GraphExecutor {
     }
 
     /// Executes the systems in the graph
-    pub fn execute(&mut self, world_ptr: NonNull<World>, stop_on_error: bool) -> Result<Vec<GraphExecutorError>, GraphExecutorError> {
+    pub fn execute(&mut self, mut world_ptr: NonNull<World>, stop_on_error: bool) -> Result<Vec<GraphExecutorError>, GraphExecutorError> {
         let mut stack = VecDeque::new();
         let mut visited = HashSet::new();
 
@@ -91,6 +91,25 @@ impl GraphExecutor {
                 possible_errors.push(e);
                 unimplemented!("Cannot resume topological execution from error"); // TODO: resume topological execution from error
             }
+
+            let world = unsafe { world_ptr.as_mut() };
+            if let Some(mut queue) = world.try_get_resource_mut::<CommandQueue>() {
+                // Safety: Commands only borrows world.entities when adding commands
+                let world = unsafe { world_ptr.as_mut() };
+                let mut commands = Commands::new(&mut queue, world);
+
+                let world = unsafe { world_ptr.as_mut() };
+                if let Err(e) = commands.execute(world)
+                        .map_err(|e| GraphExecutorError::Command(e)) {
+
+                    if stop_on_error {
+                        return Err(e);
+                    }
+    
+                    possible_errors.push(e);
+                    unimplemented!("Cannot resume topological execution from error"); // TODO: resume topological execution from error
+                }
+            }
         }
 
         Ok(possible_errors)

lyra-game/src/plugin.rs

@@ -1,4 +1,4 @@
-use lyra_ecs::Commands;
+use lyra_ecs::CommandQueue;
 use lyra_resource::ResourceManager;
 
 use crate::EventsPlugin;
@@ -109,6 +109,7 @@ pub struct DefaultPlugins;
 
 impl Plugin for DefaultPlugins {
     fn setup(&self, game: &mut Game) {
+        CommandQueuePlugin.setup(game);
         EventsPlugin.setup(game);
         InputPlugin.setup(game);
         ResourceManagerPlugin.setup(game);
@@ -116,3 +117,14 @@ impl Plugin for DefaultPlugins {
         DeltaTimePlugin.setup(game);
     }
 }
+
+/// A plugin that creates a CommandQueue, and inserts it into the world as a Resource.
+/// The queue is processed at the end of every system execution in the GraphExecutor.
+#[derive(Default)]
+pub struct CommandQueuePlugin;
+
+impl Plugin for CommandQueuePlugin {
+    fn setup(&self, game: &mut Game) {
+        game.world_mut().add_resource(CommandQueue::default());
+    }
+}

lyra-scripting/src/lua/script.rs

@@ -47,9 +47,6 @@ impl ScriptHost for LuaHost {
             provider.setup_script(script_data, ctx)?;
         }
 
-        let ctx = ctx.lock().expect("Failure to get Lua ScriptContext");
-        try_call_lua_function(&ctx, "on_init")?;
-
         Ok(())
     }
 

lyra-scripting/src/lua/system.rs

@@ -1,7 +1,5 @@
-use std::ptr::NonNull;
-
 use anyhow::anyhow;
-use lyra_ecs::{query::{Entities, ResMut, View}, CommandQueue, Commands, World};
+use lyra_ecs::{query::{Entities, ResMut, View}, World};
 use lyra_game::{game::GameStages, plugin::Plugin};
 use lyra_reflect::TypeRegistry;
 use lyra_resource::ResourceManager;
@@ -12,15 +10,13 @@ use crate::{GameScriptExt, ScriptApiProviders, ScriptContexts, ScriptData, Scrip
 use super::{providers::{LyraEcsApiProvider, LyraMathApiProvider, UtilityApiProvider}, LuaContext, LuaHost, LuaLoader, LuaScript};
 
 /// A system that creates the script contexts in the world as new scripts are found
-pub fn lua_scripts_create_contexts<'a>(
+pub fn lua_scripts_create_contexts(
     world: &mut World,
     mut host: ResMut<LuaHost>,
     mut contexts: ResMut<ScriptContexts<LuaContext>>,
     mut providers: ResMut<ScriptApiProviders<LuaHost>>,
     view: View<(Entities, &ScriptList<LuaScript>)>,
 ) -> anyhow::Result<()> {
-    world.add_resource_default::<CommandQueue>();
-
     for (en, scripts) in view.into_iter() {
         for script in scripts.iter() {
             if !contexts.has_context(script.id()) {
@@ -43,6 +39,24 @@ pub fn lua_scripts_create_contexts<'a>(
                     host.setup_script(&script_data, &mut script_ctx, &mut providers)?;
                     trace!("Finished setting up script");
 
+                    // call on_init, handle the error
+                    let world_ptr = ScriptWorldPtr::from_ref(&world);
+                    match host.call_script(
+                        world_ptr,
+                        &script_data,
+                        &mut script_ctx,
+                        &mut providers,
+                        "on_init",
+                    ) {
+                        Ok(()) => {}
+                        Err(e) => match e {
+                            ScriptError::MluaError(m) => {
+                                error!("Script '{}' ran into an error: {}", script.name(), m);
+                            }
+                            ScriptError::Other(_) => return Err(e.into()),
+                        },
+                    }
+
                     contexts.add_context(script.id(), script_ctx);
                     break;
                 } else {
@@ -52,14 +66,6 @@ pub fn lua_scripts_create_contexts<'a>(
         }
     }
 
-    let mut ptr = NonNull::from(world);
-    let world = unsafe { ptr.as_ref() };
-    let mut queue = world.get_resource_mut::<CommandQueue>();
-
-    let mut commands = Commands::new(&mut queue, unsafe { ptr.as_mut() });
-    commands.execute(unsafe { ptr.as_mut() }).unwrap();
-    //commands.execute(unsafe { world_ptr.as_mut() } )?;
-
     Ok(())
 }
 

lyra-scripting/src/lua/world.rs

@@ -1,8 +1,8 @@
 use std::{ptr::NonNull, sync::Arc};
 
-use crate::{ScriptBorrow, ScriptDynamicBundle, ScriptEntity, ScriptWorldPtr};
+use crate::{ScriptBorrow, ScriptEntity, ScriptWorldPtr};
 use elua::AsLua;
-use lyra_ecs::{query::dynamic::QueryDynamicType, Commands, DynamicBundle};
+use lyra_ecs::{query::dynamic::QueryDynamicType, CommandQueue, Commands, DynamicBundle, World};
 use lyra_reflect::{ReflectWorldExt, RegisteredType, TypeRegistry};
 use lyra_resource::ResourceManager;
 
@@ -64,10 +64,38 @@ impl elua::Userdata for ScriptWorldPtr {
         builder: &mut elua::UserdataBuilder<'a, Self>,
     ) -> elua::Result<()> {
         builder
-            .method_mut("spawn", |_, this, bundle: ScriptDynamicBundle| {
+            .method_mut("spawn", |_, this, vals: elua::ValueVec| {
                 let world = this.as_mut();
 
-                Ok(ScriptEntity(world.spawn(bundle.0)))
+                let mut bundle = DynamicBundle::new();
+
+                //while let Some(val) = vals.pop_front() {
+                for (i, val) in vals.into_iter().enumerate() {
+                    let ud = val.as_userdata().ok_or(
+                        elua::Error::bad_arg(
+                            Some("World:spawn"),
+                            2 + i as i32, // i starts at 0
+                            Some("components..."),
+                            Arc::new(elua::Error::runtime("provided component is not userdata")),
+                        ))?;
+                    
+                    let script_brw = ud.execute_method::<_, ScriptBorrow>(FN_NAME_INTERNAL_REFLECT, ())?;
+                    let reflect = script_brw.reflect_branch.as_component_unchecked();
+
+                    let refl_data = script_brw.data.unwrap();
+                    //let refl_data = refl_data.as_ref();
+                    reflect.bundle_insert(&mut bundle, refl_data);
+                }
+
+                // defer the entity spawn
+                // safety: Commands borrows Entities from World, the resource borrows from the world resouces,
+                // they are borrowing different parts of World.
+                let world_ptr: *mut World = world;
+                let mut commands_queue = world.get_resource_mut::<CommandQueue>();
+                let mut commands = Commands::new(&mut commands_queue, unsafe { &mut *world_ptr });
+                let entity = commands.spawn(bundle);
+
+                Ok(ScriptEntity(entity))
             })
             .method_mut(
                 "view",