scripting: convert LuaDeltaTime into a Lua Number instead of using it as userdata

examples/testbed/scripts/test.lua

@@ -26,13 +26,14 @@ function on_update()
         Transform
     ) ]]
 
+    ---@type number
     local dt = world:resource(DeltaTime)
     --print("DeltaTime was " .. tostring(dt) .. "s")
 
     world:view(function (t)
         --print("Found entity at a really cool place: " .. tostring(t))
         --t.translation = t.translation + (Vec3.new(0, 0.5, 0) * dt:get())
-        t.translation:move_by(0, 0.5 * dt:get(), 0)
+        t.translation:move_by(0, 0.5 * dt, 0)
 
         return t
     end, Transform)

lyra-scripting/src/lua/mod.rs

@@ -47,6 +47,11 @@ pub trait RegisterLuaType {
     where
         W: Reflect + LuaProxy + LuaWrapper + Clone + elua::FromLua<'a> + elua::Userdata;
 
+    /// Registers a type to Lua that can be converted into and from Lua types.
+    fn register_lua_convert<T>(&mut self)
+    where
+        T: Clone + for<'a> elua::FromLua<'a> + for<'a> elua::AsLua<'a> + LuaWrapper + 'static;
+
     /// Registers a type to Lua that implements [`elua::TableProxy`]
     fn register_lua_table_proxy<'a, T, W>(&mut self)
     where
@@ -77,6 +82,16 @@ impl RegisterLuaType for World {
         reg_type.add_data(ReflectLuaProxy::from_lua_proxy::<W>());
     }
 
+    fn register_lua_convert<T>(&mut self)
+    where
+        T: Clone + for<'a> elua::FromLua<'a> + for<'a> elua::AsLua<'a> + LuaWrapper + 'static,
+    {
+        let mut registry = self.get_resource_mut::<TypeRegistry>();
+
+        let reg_type = registry.get_type_or_default(T::wrapped_type_id());
+        reg_type.add_data(ReflectLuaProxy::from_as_and_from_lua::<T>());
+    }
+
     fn register_lua_table_proxy<'a, T, C>(&mut self)
     where
         T: elua::TableProxy + 'static,
@@ -86,8 +101,6 @@ impl RegisterLuaType for World {
 
         let reg_type = registry.get_type_or_default(TypeId::of::<C>());
         reg_type.add_data(ReflectLuaProxy::from_table_proxy::<T>());
-        /* let reg_type = registry.get_type_or_default(TypeId::of::<C>());
-        reg_type.add_data(<ReflectedLuaTableProxy as FromType<T>>::from_type()); */
         drop(registry);
 
         let mut lookup = self.get_resource_or_else::<LuaTableProxyLookup, _>(LuaTableProxyLookup::default);

lyra-scripting/src/lua/providers/ecs.rs

@@ -1,4 +1,7 @@
-use crate::{lua::{LuaContext, wrappers::LuaDeltaTime, RegisterLuaType}, ScriptApiProvider, ScriptWorldPtr, ScriptDynamicBundle, ScriptData};
+use lyra_ecs::ResourceObject;
+use lyra_reflect::Reflect;
+
+use crate::{lua::{wrappers::LuaDeltaTime, LuaContext, RegisterLuaType, FN_NAME_INTERNAL_REFLECT_TYPE}, ScriptApiProvider, ScriptBorrow, ScriptData, ScriptDynamicBundle, ScriptWorldPtr};
 
 #[derive(Default)]
 pub struct LyraEcsApiProvider;
@@ -7,7 +10,7 @@ impl ScriptApiProvider for LyraEcsApiProvider {
     type ScriptContext = LuaContext;
 
     fn prepare_world(&mut self, world: &mut lyra_ecs::World) {
-        world.register_lua_wrapper::<LuaDeltaTime>();
+        world.register_lua_convert::<LuaDeltaTime>();
     }
 
     fn expose_api(&mut self, _: &ScriptData, ctx: &mut Self::ScriptContext) -> Result<(), crate::ScriptError> {
@@ -17,7 +20,8 @@ impl ScriptApiProvider for LyraEcsApiProvider {
         globals.set("World", ctx.create_proxy::<ScriptWorldPtr>()?)?;
         globals.set("DynamicBundle", ctx.create_proxy::<ScriptDynamicBundle>()?)?;
 
-        globals.set("DeltaTime", ctx.create_proxy::<LuaDeltaTime>()?)?;
+        let dt_table = create_reflect_table::<lyra_game::DeltaTime>(&ctx)?;
+        globals.set("DeltaTime", dt_table)?;
 
         Ok(())
     }
@@ -30,3 +34,12 @@ impl ScriptApiProvider for LyraEcsApiProvider {
         Ok(())
     }
 }
+
+fn create_reflect_table<T: Reflect + ResourceObject + Default + 'static>(lua: &elua::State) -> elua::Result<elua::Table> {
+    let table = lua.create_table()?;
+    table.set(FN_NAME_INTERNAL_REFLECT_TYPE, lua.create_function(|_, ()| {
+        Ok(ScriptBorrow::from_resource::<T>(None))
+    })?)?;
+
+    Ok(table)
+}

lyra-scripting/src/lua/proxy.rs

@@ -115,6 +115,27 @@ impl ReflectLuaProxy {
             },
         }
     }
+
+    /// Create from a type that implements FromLua and AsLua
+    pub fn from_as_and_from_lua<T>() -> Self
+    where
+        T: for<'a> elua::FromLua<'a> + for<'a> elua::AsLua<'a> + Clone
+    {
+        Self {
+            fn_as_lua: |lua, this| -> elua::Result<elua::Value> {
+                let this = unsafe { this.cast::<T>().as_ref() };
+                this.clone().as_lua(lua)
+            },
+            fn_apply: |lua, ptr, value| {
+                let this = unsafe { ptr.cast::<T>().as_mut() };
+                let new_val = T::from_lua(lua, value.clone())?;
+
+                *this = new_val;
+                
+                Ok(())
+            },
+        }
+    }
 }
 
 impl<'lua> elua::FromLua<'lua> for ScriptDynamicBundle {

lyra-scripting/src/lua/world.rs

@@ -173,10 +173,24 @@ impl elua::Userdata for ScriptWorldPtr {
 
                 Ok(())
             })
-            .method_mut("resource", |lua, this, (ty,): (elua::AnyUserdata,)| {
-                let reflect = ty
+            .method_mut("resource", |lua, this, (ty,): (elua::Value,)| {
+                let reflect = match ty {
+                    elua::Value::Userdata(ud) => {
+                        ud.execute_function::<_, ScriptBorrow>(FN_NAME_INTERNAL_REFLECT_TYPE, ())
+                            .expect("Type does not implement 'reflect_type' properly")
+                    }
+                    elua::Value::Table(t) => {
+                        let f: elua::Function = t.get(FN_NAME_INTERNAL_REFLECT_TYPE)?;
+                        f.exec::<_, ScriptBorrow>(())
+                            .expect("Type does not implement 'reflect_type' properly")
+                    }
+                    _ => {
+                        panic!("how");
+                    }
+                };
+                /* let reflect = ty
                     .execute_function::<_, ScriptBorrow>(FN_NAME_INTERNAL_REFLECT_TYPE, ())
-                    .expect("Type does not implement 'reflect_type' properly");
+                    .expect("Type does not implement 'reflect_type' properly"); */
                 
                 let res = reflect.reflect_branch.as_resource_unchecked();
                 if let Some(res_ptr) = res.reflect_ptr(this.as_mut()) {

lyra-scripting/src/lua/wrappers/delta_time.rs

@@ -1,10 +1,11 @@
+
 use std::any::TypeId;
 
 use lyra_game::DeltaTime;
-use crate::{lyra_engine, lua::{FN_NAME_INTERNAL_REFLECT_TYPE, LuaWrapper}, ScriptBorrow};
+use crate::lua::LuaWrapper;
 
-#[derive(Clone, lyra_reflect::Reflect, Default)]
-pub struct LuaDeltaTime(#[reflect(skip)] pub(crate) DeltaTime);
+#[derive(Clone, Default)]
+pub struct LuaDeltaTime(pub(crate) DeltaTime);
 
 impl std::ops::Deref for LuaDeltaTime {
     type Target = DeltaTime;
@@ -22,31 +23,13 @@ impl std::ops::DerefMut for LuaDeltaTime {
 
 impl<'lua> elua::FromLua<'lua> for LuaDeltaTime {
     fn from_lua(lua: &'lua elua::State, value: elua::Value<'lua>) -> elua::Result<Self> {
-        match value {
-            elua::Value::Userdata(ud) => Ok(ud.as_ref::<Self>()?.clone()),
-            _ => unreachable!(),
-        }
+        todo!()
     }
 }
 
-impl elua::Userdata for LuaDeltaTime {
-    fn name() -> String {
-        "DeltaTime".to_string()
-    }
-
-    fn build<'a>(state: &elua::State, builder: &mut elua::UserdataBuilder<'a, Self>) -> elua::Result<()> {
-        builder
-            .method("get", |_, this, ()| {
-                Ok(*this.0)
-            })
-            .meta_method(elua::MetaMethod::ToString, |_, this, ()| {
-                Ok(format!("{}", *this.0))
-            })
-            .function(FN_NAME_INTERNAL_REFLECT_TYPE, |_, ()| {
-                Ok(ScriptBorrow::from_resource::<DeltaTime>(None))
-            });
-
-        Ok(())
+impl<'lua> elua::AsLua<'lua> for LuaDeltaTime {
+    fn as_lua(self, lua: &'lua elua::State) -> elua::Result<elua::Value<'lua>> {
+        Ok(elua::Value::Number(*self.0 as f64))
     }
 }