From 9f68184f4a4ad4a8bc5b34257435218134fa8834 Mon Sep 17 00:00:00 2001
From: UIS <uis9936@gmail.com>
Date: Thu, 10 Dec 2020 15:23:59 +0300
Subject: [PATCH] Fix multithreading

Reorder locks in Event.cpp
---
 src/AssetManager.cpp  |  4 +---
 src/Event.cpp         | 21 ++++++++++++---------
 src/Event.hpp         |  2 +-
 src/RendererWorld.cpp |  4 ++--
 4 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/src/AssetManager.cpp b/src/AssetManager.cpp
index 033daae8..632f0771 100644
--- a/src/AssetManager.cpp
+++ b/src/AssetManager.cpp
@@ -367,9 +367,7 @@ BlockFaces &AssetManager::GetBlockModelByBlockId(BlockId block) {
 		blockFaces.faceDirectionVector[i] = Vector(roundf(vec.x), roundf(vec.y), roundf(vec.z));
 	}
 
-	blockIdToBlockFaces.insert(std::make_pair(block, blockFaces));
-
-	return blockIdToBlockFaces.find(block)->second;
+	return blockIdToBlockFaces.insert(std::make_pair(block, blockFaces)).first->second;
 }
 
 std::string AssetManager::GetAssetNameByBlockId(BlockId block) {
diff --git a/src/Event.cpp b/src/Event.cpp
index 7df71b17..7735d0e0 100644
--- a/src/Event.cpp
+++ b/src/Event.cpp
@@ -16,7 +16,7 @@ EventListener::~EventListener() {
 
 void EventListener::HandleEvent() {
 	OPTICK_EVENT();
-	if (!NotEmpty())
+	if (Empty())
 		return;
 
 	std::lock_guard<std::recursive_mutex> eventsLock (eventsMutex);
@@ -30,11 +30,14 @@ void EventListener::HandleEvent() {
 
 void EventListener::HandleAllEvents() {
 	OPTICK_EVENT();
-	if (!NotEmpty())
-		return;
 
+	//This mutexes will locked in PollEvents
 	std::lock_guard<std::recursive_mutex> eventsLock (eventsMutex);
 	std::lock_guard<std::recursive_mutex> handlersLock (handlersMutex);
+
+	if (Empty())
+		return;
+
 	while (!events.empty()) {
 		Event event = events.front();
 		events.pop();
@@ -44,11 +47,10 @@ void EventListener::HandleAllEvents() {
 	}
 }
 
-bool EventListener::NotEmpty() {
-	PollEvents();
+bool EventListener::Empty() {
 	std::lock_guard<std::recursive_mutex> eventsLock (eventsMutex);
-	bool ret = !events.empty();
-	return ret;
+	PollEvents();
+	return events.empty();
 }
 
 void EventListener::RegisterHandler(size_t eventId, const EventListener::HandlerType &data) {
@@ -58,12 +60,13 @@ void EventListener::RegisterHandler(size_t eventId, const EventListener::Handler
 
 void EventListener::PollEvents() {
 	OPTICK_EVENT();
+	std::lock_guard<std::recursive_mutex> eventsLock (eventsMutex);
+	std::lock_guard<std::recursive_mutex> handlersLock (handlersMutex);//To prevent inverse lock order
+
 	std::lock_guard<std::recursive_mutex> rawLock (rawEventsMutex);
 	if (rawEvents.empty())
 		return;
 
-	std::lock_guard<std::recursive_mutex> eventsLock (eventsMutex);
-	std::lock_guard<std::recursive_mutex> handlersLock (handlersMutex);
 	while (!rawEvents.empty()) {
 		Event event = rawEvents.front();
 		rawEvents.pop();
diff --git a/src/Event.hpp b/src/Event.hpp
index 49426ffd..15916792 100644
--- a/src/Event.hpp
+++ b/src/Event.hpp
@@ -77,7 +77,7 @@ class EventListener {
 
 	void HandleAllEvents();
 
-	bool NotEmpty();
+	bool Empty();
 
 	void RegisterHandler(size_t eventId, const HandlerType &data);
 
diff --git a/src/RendererWorld.cpp b/src/RendererWorld.cpp
index 3a04d179..ed59cc1b 100644
--- a/src/RendererWorld.cpp
+++ b/src/RendererWorld.cpp
@@ -34,7 +34,7 @@ void RendererWorld::WorkerFunction(size_t workerId) {
 
     LoopExecutionTimeController timer(std::chrono::milliseconds(50));
     while (isRunning) {
-        while (tasksListener.NotEmpty() && isRunning)
+	while (!tasksListener.Empty() && isRunning)
             tasksListener.HandleEvent();
         timer.Update();
     }
@@ -394,7 +394,7 @@ void RendererWorld::Render(RenderState & renderState) {
 				entityShader->SetUniform("color", glm::vec3(0.7f, 0, 0));
             else
 				entityShader->SetUniform("color", glm::vec3(0, 0, 0.7f));
-            glDrawArrays(GL_LINE_STRIP, 0, 36);
+	    glDrawArrays(GL_LINES, 0, 24);
         }
 	glCheckError();
     }