Animate Window_Message during transitions

Emulates the RPG_RT behavior for EasyRPG#1706 Tests 17 & 18

src/game_message.cpp

@@ -196,6 +196,12 @@ int Game_Message::WordWrap(const std::string& line, const int limit, const std::
 	return line_count;
 }
 
+void Game_Message::AdvanceAnimationFrames(int frames) {
+	if (window) {
+		window->AdvanceAnimationFrames(frames);
+	}
+}
+
 void Game_Message::Update() {
 	if (window) {
 		window->Update();

src/game_message.h

@@ -39,6 +39,9 @@ namespace Game_Message {
 
 	void Update();
 
+	/** Calls AdvanceAnimationFrames() on the Window_Message */
+	void AdvanceAnimationFrames(int frames);
+
 	/** Reset the face graphic. */
 	void ClearFace();
 

src/scene_map.cpp

@@ -111,7 +111,7 @@ void Scene_Map::Start2(MapUpdateAsyncContext actx) {
 	// in order to make async logic work properly.
 	auto& transition = Transition::instance();
 	if (transition.IsErased()) {
-		transition.InitShow(Transition::TransitionFadeIn, this);
+		InitTransitionShow(Transition::TransitionFadeIn);
 	}
 
 	// Call any requested scenes when transition is done.
@@ -160,7 +160,7 @@ void Scene_Map::TransitionIn(SceneType prev_scene) {
 	}
 
 	if (prev_scene == Scene::Battle) {
-		transition.InitShow(Game_System::GetTransition(Game_System::Transition_EndBattleShow), this);
+		InitTransitionShow(Game_System::GetTransition(Game_System::Transition_EndBattleShow));
 		return;
 	}
 
@@ -182,7 +182,7 @@ void Scene_Map::TransitionOut(SceneType next_scene) {
 	}
 
 	if (next_scene == Scene::Debug) {
-		transition.InitErase(Transition::TransitionCutOut, this);
+		InitTransitionErase(Transition::TransitionCutOut);
 		return;
 	}
 
@@ -191,22 +191,23 @@ void Scene_Map::TransitionOut(SceneType next_scene) {
 			auto tt = Game_System::GetTransition(Game_System::Transition_BeginBattleErase);
 			if (tt == Transition::TransitionNone) {
 				// If transition type is none, RPG_RT flashes and then waits 40 frames before starting the battle.
-				transition.InitErase(Transition::TransitionCutOut, this, 40);
+				InitTransitionErase(Transition::TransitionCutOut, 40);
 			} else {
-				transition.InitErase(tt, this);
+				InitTransitionErase(tt);
 			}
 			transition.PrependFlashes(31, 31, 31, 31, 10, 2);
 		} else {
 			// If screen is already erased, RPG_RT does nothing for 40 frames.
-			transition.InitErase(Transition::TransitionNone, this, 40);
+			InitTransitionErase(Transition::TransitionNone, 40);
 		}
 		return;
 	}
 	if (next_scene == Scene::Gameover) {
-		transition.InitErase(Transition::TransitionFadeOut, this);
+		InitTransitionErase(Transition::TransitionFadeOut);
 		return;
 	}
-	Scene::TransitionOut(next_scene);
+
+	InitTransitionErase(Transition::TransitionFadeOut, 6);
 }
 
 void Scene_Map::DrawBackground(Bitmap& dst) {
@@ -309,7 +310,7 @@ void Scene_Map::StartPendingTeleport(TeleportParams tp) {
 	request->Start();
 
 	if (!transition.IsErased() && tp.erase_screen) {
-		transition.InitErase(Game_System::GetTransition(Game_System::Transition_TeleportErase), this);
+		InitTransitionErase(Game_System::GetTransition(Game_System::Transition_TeleportErase));
 	}
 
 	AsyncNext([=]() { FinishPendingTeleport(tp); });
@@ -347,9 +348,9 @@ void Scene_Map::FinishPendingTeleport2(MapUpdateAsyncContext actx, TeleportParam
 
 	// This logic was tested against RPG_RT and works this way ...
 	if (tp.use_default_transition_in && transition.IsErased()) {
-		transition.InitShow(Transition::TransitionFadeIn, this);
+		InitTransitionShow(Transition::TransitionFadeIn);
 	} else if (!tp.use_default_transition_in && !screen_erased_by_event) {
-		transition.InitShow(Game_System::GetTransition(Game_System::Transition_TeleportShow), this);
+		InitTransitionShow(Game_System::GetTransition(Game_System::Transition_TeleportShow));
 	}
 
 	// Call any requested scenes when transition is done.
@@ -411,16 +412,14 @@ void Scene_Map::OnAsyncSuspend(F&& f, AsyncOp aop, bool is_preupdate) {
 		return;
 	}
 
-	auto& transition = Transition::instance();
-
 	if (aop.GetType() == AsyncOp::eEraseScreen) {
 		auto tt = static_cast<Transition::Type>(aop.GetTransitionType());
 		if (tt == Transition::TransitionNone) {
 			// Emulates an RPG_RT bug where instantaneous transitions cause a
 			// 30 frame pause and then make the screen black.
-			transition.InitErase(Transition::TransitionCutOut, this, 30);
+			InitTransitionErase(Transition::TransitionCutOut, 30);
 		} else {
-			transition.InitErase(tt, this);
+			InitTransitionErase(tt);
 		}
 
 		if (!is_preupdate) {
@@ -431,7 +430,7 @@ void Scene_Map::OnAsyncSuspend(F&& f, AsyncOp aop, bool is_preupdate) {
 
 	if (aop.GetType() == AsyncOp::eShowScreen) {
 		auto tt = static_cast<Transition::Type>(aop.GetTransitionType());
-		transition.InitShow(tt, this);
+		InitTransitionShow(tt);
 		screen_erased_by_event = false;
 	}
 
@@ -442,7 +441,7 @@ void Scene_Map::OnAsyncSuspend(F&& f, AsyncOp aop, bool is_preupdate) {
 
 		Game_System::BgmFade(800);
 
-		transition.InitErase(Transition::TransitionFadeOut, Scene::instance.get());
+		InitTransitionErase(Transition::TransitionFadeOut);
 
 		AsyncNext([=]() { StartInn(); });
 		return;
@@ -480,9 +479,7 @@ void Scene_Map::FinishInn() {
 	// was issued previously.
 	screen_erased_by_event = false;
 
-	auto& transition = Transition::instance();
-
-	transition.InitShow(Transition::TransitionFadeIn, Scene::instance.get());
+	InitTransitionShow(Transition::TransitionFadeIn);
 	Game_System::BgmPlay(music_before_inn);
 
 	// Full heal
@@ -501,3 +498,23 @@ void Scene_Map::UpdateInn() {
 		FinishInn();
 	}
 }
+
+void Scene_Map::InitTransitionShow(Transition::Type tt, int frames) {
+	// In rare cases where a message and a transition are triggered on the same frame, RPG_RT
+	// will still animate the message box open/close and the transition effect will show
+	// the resulting message box state. This can affect interpreter timing so we try to emulate it.
+	// See #1706 Tests 17 and 18
+	auto cb = [this](int frames) {
+		message_window->AdvanceAnimationFrames(frames);
+	};
+	Transition::instance().InitShow(tt, this, frames, cb);
+}
+
+void Scene_Map::InitTransitionErase(Transition::Type tt, int frames) {
+	// See comments in InitTransitionShow
+	auto cb = [this](int frames) {
+		message_window->AdvanceAnimationFrames(frames);
+	};
+	Transition::instance().InitErase(tt, this, frames, cb);
+}
+

src/scene_map.h

@@ -24,6 +24,7 @@
 #include "window_message.h"
 #include "window_varlist.h"
 #include "game_map.h"
+#include "transition.h"
 
 /**
  * Scene Map class.
@@ -84,6 +85,9 @@ class Scene_Map: public Scene {
 	void UpdateInn();
 	void FinishInn();
 
+	void InitTransitionShow(Transition::Type tt, int frames = -1);
+	void InitTransitionErase(Transition::Type tt, int frames = -1);
+
 	template <typename F> void AsyncNext(F&& f);
 	template <typename F> void OnAsyncSuspend(F&& f, AsyncOp aop, bool is_preupdate);
 

src/transition.cpp

@@ -32,6 +32,7 @@
 #include "drawable.h"
 #include "drawable_mgr.h"
 #include "output.h"
+#include "game_message.h"
 
 int Transition::GetDefaultFrames(Transition::Type type)
 {
@@ -66,7 +67,7 @@ void Transition::PrependFlashes(int r, int g, int b, int p, int duration, int it
 	flash_iterations = std::max(1, iterations);
 }
 
-void Transition::Init(Type type, Scene *linked_scene, int duration, bool erase) {
+void Transition::Init(Type type, Scene *linked_scene, int duration, bool erase, const TransitionCallback& cb) {
 	if (duration < 0) {
 		duration = GetDefaultFrames(type);
 	}
@@ -86,6 +87,11 @@ void Transition::Init(Type type, Scene *linked_scene, int duration, bool erase)
 		return;
 	}
 
+	// Allow visual game logic to animate to the end of transition.
+	if (cb) {
+		cb(duration);
+	}
+
 	// FIXME: Break this dependency on DisplayUI
 	if (screen_erased) {
 		screen1 = Bitmap::Create(DisplayUi->GetWidth(), DisplayUi->GetHeight(), Color(0, 0, 0, 255));

src/transition.h

@@ -86,23 +86,27 @@ class Transition : public Drawable {
 	/** @return the transition singleton */
 	static Transition& instance();
 
+	using TransitionCallback = std::function<void(int)>;
+
 	/**
 	 * Initiate a ShowScreen transition
 	 *
 	 * @param type transition type.
 	 * @param linked_scene scene transitioning, it should be either the scene summoning (this) or the current instance (Scene::instance.get())
 	 * @param duration transition duration, set to -1 to use the default number of frames.
+	 * @param cb callback to call with number of frames of transition before it occurs.
 	 */
-	void InitShow(Type type, Scene *linked_scene, int duration = -1);
+	void InitShow(Type type, Scene *linked_scene, int duration = -1, const TransitionCallback& cb = {});
 
 	/**
 	 * Initiate an EraseScreen transition
 	 *
 	 * @param type transition type.
 	 * @param linked_scene scene transitioning, it should be either the scene summoning (this) or the current instance (Scene::instance.get())
 	 * @param duration transition duration, set to -1 to use the default number of frames.
+	 * @param cb callback to call with number of frames of transition before it occurs.
 	 */
-	void InitErase(Type type, Scene *linked_scene, int duration = -1);
+	void InitErase(Type type, Scene *linked_scene, int duration = -1, const TransitionCallback& cb = {});
 
 	void PrependFlashes(int r, int g, int b, int power, int duration, int iterations);
 
@@ -114,7 +118,7 @@ class Transition : public Drawable {
 
 private:
 	Transition();
-	void Init(Type type, Scene *linked_scene, int duration, bool erase);
+	void Init(Type type, Scene *linked_scene, int duration, bool erase, const TransitionCallback& cb);
 
 	const uint32_t size_random_blocks = 4;
 
@@ -153,12 +157,12 @@ inline Transition& Transition::instance() {
 	return transition;
 }
 
-inline void Transition::InitShow(Type type, Scene *linked_scene, int duration) {
-	Init(type, linked_scene, duration, false);
+inline void Transition::InitShow(Type type, Scene *linked_scene, int duration, const TransitionCallback& cb) {
+	Init(type, linked_scene, duration, false, cb);
 }
 
-inline void Transition::InitErase(Type type, Scene *linked_scene, int duration) {
-	Init(type, linked_scene, duration, true);
+inline void Transition::InitErase(Type type, Scene *linked_scene, int duration, const TransitionCallback& cb) {
+	Init(type, linked_scene, duration, true, cb);
 }
 
 inline bool Transition::IsActive() {

src/window_message.cpp

@@ -359,6 +359,21 @@ void Window_Message::ResetWindow() {
 
 }
 
+void Window_Message::AdvanceAnimationFrames(int frames) {
+	if (frames == 0) {
+		return;
+	}
+
+	close_started_this_frame = false;
+
+	while (frames > 0) {
+		bool was_closing = IsClosing();
+		Window::Update();
+		close_finished_this_frame = was_closing && !IsClosing();
+		--frames;
+	}
+}
+
 void Window_Message::Update() {
 	if (IsOpening()) { DebugLog("%d: MSG OPENING"); }
 	if (IsClosing()) { DebugLog("%d: MSG CLOSING"); }

src/window_message.h

@@ -88,11 +88,19 @@ class Window_Message: public Window_Selectable {
 
 	void Update() override;
 
+	/**
+	 * Force the window animations to advance by a number of frames.
+	 * This is exercised by some edge cases with transitions
+	 * 
+	 * @params frames number of frames of the transition.
+	 */
+	void AdvanceAnimationFrames(int frames);
+
 	/**
 	 * Continues outputting more text. Also handles the
 	 * CommandCode parsing.
 	 */
-	virtual void UpdateMessage();
+	void UpdateMessage();
 
 	/**
 	 * Stub. For choice.