Merge pull request #5671 from Web-eWorks/game-event-queue

Refactor Event Queues

data/libs/Event.lua

@@ -25,26 +25,80 @@
 --
 
 local Engine = require 'Engine'
+local utils  = require 'utils'
 
-local pending = {}
-local callbacks = {}
-local do_callback = {}
-
-local do_callback_normal = function (cb, p)
-	cb(table.unpack(p.event))
+local do_callback_normal = function (cb, ev)
+	cb.func(table.unpack(ev))
 end
-local do_callback_timed = function (cb, p)
+local do_callback_timed = function (cb, ev)
 	local d = debug.getinfo(cb)
 
 	local tstart = Engine.ticks
-	cb(table.unpack(p.event))
+	cb.func(table.unpack(ev))
 	local tend = Engine.ticks
 
-	print(string.format("DEBUG: %s %dms %s:%d", p.name, tend-tstart, d.source, d.linedefined))
+	print(string.format("DEBUG: %s %dms %s:%d", ev.name, tend-tstart, d.source, d.linedefined))
+end
+
+---@class EventBase
+---@field callbacks table
+---@field debugger table
+local Event = utils.inherits(nil, "Event")
+
+function Event:Register(name, module, func)
+
+	for _, cb in ipairs(self.callbacks[name]) do
+		-- Update registered callback
+		if cb.module == module then
+			cb.func = func
+			return
+		end
+	end
+
+	table.insert(self.callbacks[name], { module = module, func = func })
+end
+
+function Event:Deregister(name, module, func)
+	for i, cb in ipairs(self.callbacks[name]) do
+		if cb.module == module and cb.func == func then
+			table.remove(self.callbacks[name], i)
+			return
+		end
+	end
+end
+
+function Event:_Emit()
+	while #self > 0 do
+		local ev = table.remove(self, 1)
+		local executor = self.debugger[ev.name] or do_callback_normal
+
+		for _, cb in ipairs(self.callbacks[ev.name]) do
+			executor(cb, ev)
+		end
+	end
 end
 
-local Event
-Event = {
+function Event:_Dump()
+	for ev, list in pairs(self.callbacks) do
+		print("event: " .. ev)
+
+		for _, v in ipairs(list) do
+			print("\t{module} -> {func}" % v)
+		end
+	end
+end
+
+-- Note: this function is written this way to preserve the existing
+-- interface to Event.Register(name, callback) as well as provide helpers
+-- to automatically acquire module names when registering callbacks
+Event.New = function()
+	---@class EventQueue : EventBase
+	local self = setmetatable({}, Event.meta)
+	local super = Event
+
+	self.callbacks = utils.automagic()
+	self.debugger = {}
+
 	--
 	-- Function: Register
 	--
@@ -76,11 +130,9 @@ Event = {
 	--
 	--   stable
 	--
-	Register = function (name, cb)
-		if not callbacks[name] then callbacks[name] = {} end
-		callbacks[name][cb] = cb;
-        if not do_callback[name] then do_callback[name] = do_callback_normal end
-	end,
+	self.Register = function (name, cb)
+		super.Register(self, name, package.modulename(2), cb)
+	end
 
 	--
 	-- Function: Deregister
@@ -107,10 +159,9 @@ Event = {
 	--
 	--   stable
 	--
-	Deregister = function (name, cb)
-		if not callbacks[name] then return end
-		callbacks[name][cb] = nil
-	end,
+	self.Deregister = function (name, cb)
+		super.Deregister(self, name, package.modulename(2), cb)
+	end
 
 	--
 	-- Function: Queue
@@ -138,9 +189,9 @@ Event = {
 	--
 	--   stable
 	--
-	Queue = function (name, ...)
-		table.insert(pending, { name = name, event = {...} })
-	end,
+	self.Queue = function (name, ...)
+		table.insert(self, { name = name, ... })
+	end
 
 	--
 	-- Function: DebugTimer
@@ -167,27 +218,24 @@ Event = {
 	--   debug
     --
 
-    DebugTimer = function (name, enabled)
+    self.DebugTimer = function (name, enabled)
 		do_callback[name] = enabled and do_callback_timed or do_callback_normal
-	end,
+	end
 
 	-- internal method, called from C++
-	_Clear = function ()
-		pending = {}
-	end,
+	self._Clear = function ()
+		for i = #self, 1, -1 do
+			self[i] = nil
+		end
+	end
 
 	-- internal method, called from C++
-	_Emit = function ()
-		while #pending > 0 do
-			local p = table.remove(pending, 1)
-			if callbacks[p.name] then
-				for cb,_ in pairs(callbacks[p.name]) do
-					do_callback[p.name](cb, p)
-				end
-			end
-		end
+	self._Emit = function ()
+		super._Emit(self)
 	end
-}
+
+	return self
+end
 
 --
 -- Event: onGameStart
@@ -854,4 +902,4 @@ Event = {
 --   experimental
 --
 
-return Event
+return Event.New()

data/libs/autoload.lua

@@ -49,9 +49,9 @@ string.interp = function (s, t)
 	local i = 0
 	return (s:gsub('(%b{})', function(w)
 		if #w > 2 then
-			return t[w:sub(2, -2)] or w
+			return tostring(t[w:sub(2, -2)]) or w
 		else
-			i = i + 1; return t[i] or w
+			i = i + 1; return tostring(t[i]) or w
 		end
 	end))
 end

data/meta/_Core.lua

@@ -32,6 +32,17 @@ package.core = {}
 ---@param name string? dot-qualified name of the package to trigger reimport for
 package.reimport = function(name) end
 
+--- Get the module name of the file where this function is called
+---@return string moduleName
+package.thisModule = function() end
+
+--- Get the module name of the function N stack levels above package.modulename
+--- in the execution stack. Note: tail calls may affect the accuracy of this
+--- function.
+---@param index integer number of stack levels above package.modulename(), minimum 1
+---@return string moduleName
+package.modulename = function(index) end
+
 --- Log the specified string at the Warning semantic level
 function logWarning(string) end
 

data/pigui/baseui.lua

@@ -7,6 +7,9 @@ local pigui = Engine.pigui
 local ui = require 'pigui.libs.forwarded'
 ui.rescaleUI = require 'pigui.libs.rescale-ui'
 
+---@type EventQueue
+ui.Events = pigui.event_queue
+
 --
 -- Function: ui.rescaleFraction
 --

src/Game.cpp

@@ -18,6 +18,7 @@
 #include "galaxy/Economy.h"
 #include "lua/LuaEvent.h"
 #include "lua/LuaSerializer.h"
+#include "pigui/LuaPiGui.h"
 #if WITH_OBJECTVIEWER
 #include "ObjectViewerView.h"
 #endif
@@ -880,9 +881,11 @@ void Game::EmitPauseState(bool paused)
 	if (paused) {
 		// Notify UI that time is paused.
 		LuaEvent::Queue("onGamePaused");
+		LuaEvent::Queue(PiGui::GetEventQueue(), "onGamePaused");
 	} else {
 		// Notify the UI that time is running again.
 		LuaEvent::Queue("onGameResumed");
+		LuaEvent::Queue(PiGui::GetEventQueue(), "onGameResumed");
 	}
 	LuaEvent::Emit();
 }

src/Pi.cpp

@@ -614,6 +614,7 @@ void StartupScreen::Update(float deltaTime)
 	}
 
 	Pi::pigui->NewFrame();
+	PiGui::EmitEvents();
 	PiGui::RunHandler(GetProgress(), "init");
 	Pi::pigui->Render();
 }
@@ -684,6 +685,7 @@ void MainMenu::Update(float deltaTime)
 	Pi::intro->Draw(deltaTime);
 
 	Pi::pigui->NewFrame();
+	PiGui::EmitEvents();
 	PiGui::RunHandler(deltaTime, "mainMenu");
 
 	perfInfoDisplay->Update(deltaTime);
@@ -1037,6 +1039,7 @@ void GameLoop::Update(float deltaTime)
 			Pi::luaConsole->Draw();
 		else {
 			Pi::GetView()->DrawPiGui();
+			PiGui::EmitEvents();
 			PiGui::RunHandler(deltaTime, "game");
 		}
 	}
@@ -1101,6 +1104,9 @@ void GameLoop::Update(float deltaTime)
 
 void GameLoop::End()
 {
+	// Process any pending UI events
+	PiGui::EmitEvents();
+
 	// When Pi::game goes, so too goes the death view.
 	Pi::SetView(0);
 

src/Ship.cpp

@@ -15,6 +15,7 @@
 #include "Lang.h"
 #include "Missile.h"
 #include "NavLights.h"
+#include "Pi.h"
 #include "Planet.h"
 #include "Player.h" // <-- Here only for 1 occurrence of "Pi::player" in Ship::Explode
 #include "Sensors.h"

src/lua/Lua.cpp

@@ -103,6 +103,8 @@ namespace Lua {
 		LuaObject<LuaSerializer>::RegisterClass();
 		LuaObject<LuaTimer>::RegisterClass();
 
+		LuaEvent::Init();
+
 		LuaConstants::Register(Lua::manager->GetLuaState());
 		LuaLang::Register();
 		LuaEconomy::Register();
@@ -139,6 +141,8 @@ namespace Lua {
 
 	void UninitModules()
 	{
+		LuaEvent::Uninit();
+
 		delete Pi::luaNameGen;
 
 		delete Pi::luaSerializer;

src/lua/LuaEvent.cpp

@@ -6,32 +6,52 @@
 #include "LuaObject.h"
 #include "LuaUtils.h"
 
+#include "core/Log.h"
+
 namespace LuaEvent {
 
+	static LuaRef s_eventTable;
+
 	static bool _get_method_onto_stack(lua_State *l, const char *method)
 	{
 		LUA_DEBUG_START(l);
-
-		int top = lua_gettop(l);
-
-		if (!pi_lua_import(l, "Event"))
+		if (!s_eventTable.IsValid())
 			return false;
 
+		s_eventTable.PushCopyToStack();
+
 		lua_getfield(l, -1, method);
 		if (!lua_isfunction(l, -1)) {
 			lua_pop(l, 2);
 			LUA_DEBUG_END(l, 0);
 			return false;
 		}
 
-		lua_insert(l, top + 1);
-		lua_settop(l, top + 1);
-
+		lua_replace(l, -2);
 		LUA_DEBUG_END(l, 1);
 
 		return true;
 	}
 
+	void Init()
+	{
+		lua_State *l = Lua::manager->GetLuaState();
+
+		if (!pi_lua_import(l, "Event")) {
+			Log::Error("Could not load lua Event queue implementation!");
+			return;
+		}
+
+		s_eventTable = LuaRef(l, -1);
+
+		lua_pop(l, 1);
+	}
+
+	void Uninit()
+	{
+		s_eventTable.Unref();
+	}
+
 	void Clear()
 	{
 		lua_State *l = Lua::manager->GetLuaState();
@@ -52,19 +72,9 @@ namespace LuaEvent {
 		LUA_DEBUG_END(l, 0);
 	}
 
-	void QueueInternal(const char *event, const ArgsBase &args)
+	LuaRef &GetEventQueue()
 	{
-		lua_State *l = Lua::manager->GetLuaState();
-
-		LUA_DEBUG_START(l);
-		if (!_get_method_onto_stack(l, "Queue")) return;
-
-		int top = lua_gettop(l);
-		lua_pushstring(l, event);
-		args.PrepareStack(l);
-		pi_lua_protected_call(l, lua_gettop(l) - top, 0);
-
-		LUA_DEBUG_END(l, 0);
+		return s_eventTable;
 	}
 
 } // namespace LuaEvent