examples/lua-scripting/scripts/test.lua

@@ -93,6 +93,13 @@ function on_update()
     for _, transform in changed_res:iter() do
         print("Entity transform changed to: '" .. tostring(transform) .. "' on tick " .. tostring(world:get_tick()))
     end
+
+    local tick_view = View.new(TickOf(Transform))
+    local tick_res = world:view_query(tick_view)
+    ---@param tick number
+    for _, tick in tick_res:iter() do
+        print("Entity transform last changed on tick " .. tostring(tick))
+    end
 end
 
 --[[ function on_post_update()

lyra-scripting/scripts/lua/ecs.lua

@@ -42,6 +42,15 @@ end
 ---@see OrQuery
 ---@param ... function|table|userdata
 ---@return OrQuery
-function Not(...)
+function Or(...)
     return OrQuery.new(...)
+end
+
+---Create a `TickOfQuery` for retrieving the tick of the resource or component on the entity.
+---
+---@see TickOfQuery
+---@param ... table|userdata
+---@return TickOfQuery
+function TickOf(...)
+    return TickOfQuery.new(...)
 end

lyra-scripting/src/lua/ecs/query/mod.rs

@@ -13,6 +13,9 @@ pub use not::*;
 mod or;
 pub use or::*;
 
+mod tick_of;
+pub use tick_of::*;
+
 use lyra_ecs::Entity;
 
 use crate::{

lyra-scripting/src/lua/ecs/query/tick_of.rs

@@ -0,0 +1,54 @@
+use crate::{
+    lua::{LuaComponent, FN_NAME_INTERNAL_ECS_QUERY_RESULT},
+    ReflectBranch, ScriptEntity, ScriptWorldPtr,
+};
+
+use super::LuaQueryResult;
+
+#[derive(Clone)]
+pub struct LuaTickOfQuery(LuaComponent);
+
+impl mlua::FromLua for LuaTickOfQuery {
+    fn from_lua(value: mlua::Value, _: &mlua::Lua) -> mlua::Result<Self> {
+        let tyname = value.type_name();
+        value
+            .as_userdata()
+            .ok_or(mlua::Error::FromLuaConversionError {
+                from: tyname,
+                to: "TickOfQuery".into(),
+                message: None,
+            })
+            .and_then(|ud| ud.borrow::<Self>())
+            .map(|ud| ud.clone())
+    }
+}
+
+impl mlua::UserData for LuaTickOfQuery {
+    fn add_methods<M: mlua::UserDataMethods<Self>>(methods: &mut M) {
+        methods.add_function("new", |_, comp: LuaComponent| Ok(Self(comp)));
+
+        methods.add_method(
+            FN_NAME_INTERNAL_ECS_QUERY_RESULT,
+            |_, this, (world, en): (ScriptWorldPtr, ScriptEntity)| {
+                let world = world.read();
+                let reflect = this.0.reflect_type()?;
+                match &reflect.reflect_branch {
+                    ReflectBranch::Component(comp) => {
+                        if let Some(tick) = comp.reflect_tick(&world, *en) {
+                            Ok(LuaQueryResult::Some(mlua::Value::Number(*tick as _)))
+                        } else {
+                            Ok(LuaQueryResult::FilterDeny)
+                        }
+                    }
+                    ReflectBranch::Resource(res) => {
+                        if let Some(tick) = res.reflect_tick(&world) {
+                            Ok(LuaQueryResult::Some(mlua::Value::Number(*tick as _)))
+                        } else {
+                            Ok(LuaQueryResult::FilterDeny)
+                        }
+                    }
+                }
+            },
+        );
+    }
+}

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

@@ -1,7 +1,7 @@
 use lyra_ecs::ResourceObject;
 use lyra_reflect::Reflect;
 
-use crate::{lua::{ecs::{query::{LuaChangedQuery, LuaHasQuery, LuaNotQuery, LuaOrQuery, LuaResQuery}, View}, wrappers::*, LuaContext, LuaWrapper, RegisterLuaType, FN_NAME_INTERNAL_REFLECT, FN_NAME_INTERNAL_REFLECT_TYPE}, ScriptApiProvider, ScriptBorrow, ScriptData, ScriptDynamicBundle, ScriptWorldPtr};
+use crate::{lua::{ecs::{query::{LuaChangedQuery, LuaHasQuery, LuaNotQuery, LuaOrQuery, LuaResQuery, LuaTickOfQuery}, View}, wrappers::*, LuaContext, LuaWrapper, RegisterLuaType, FN_NAME_INTERNAL_REFLECT, FN_NAME_INTERNAL_REFLECT_TYPE}, ScriptApiProvider, ScriptBorrow, ScriptData, ScriptDynamicBundle, ScriptWorldPtr};
 
 //fn register_lua_proxy::<T: 
 
@@ -50,6 +50,7 @@ impl ScriptApiProvider for LyraEcsApiProvider {
         globals.set("HasQuery", ctx.create_proxy::<LuaHasQuery>()?)?;
         globals.set("NotQuery", ctx.create_proxy::<LuaNotQuery>()?)?;
         globals.set("OrQuery", ctx.create_proxy::<LuaOrQuery>()?)?;
+        globals.set("TickOfQuery", ctx.create_proxy::<LuaTickOfQuery>()?)?;
 
         expose_comp_table_wrapper::<LuaCamera>(&ctx, &globals, "Camera")?;
         expose_comp_table_wrapper::<LuaFreeFlyCamera>(&ctx, &globals, "FreeFlyCamera")?;