From 77b017a0830410bc06fc4747d559b75e306dcdcc Mon Sep 17 00:00:00 2001
From: oldmud0 <oldmud0@users.noreply.github.com>
Date: Wed, 5 Jan 2022 21:39:23 -0600
Subject: [PATCH] Fix MSVC builds freezing due to AOLayer concurrency issue

Variables accessed across threads should be atomic.

Also gave AOLayer its own thread pool and switched some lock calls to use QMutexLocker semantics.
---
 CMakeLists.txt    |  4 ++--
 include/aolayer.h |  2 +-
 src/aolayer.cpp   | 25 ++++++++++++++++---------
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b6b0210..31559ad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,9 +31,9 @@ endif()
 target_include_directories(Attorney_Online PRIVATE include)
 
 # Target Lib
-find_package(Qt5 COMPONENTS Core Gui Network Widgets REQUIRED)
+find_package(Qt5 COMPONENTS Core Gui Network Widgets Concurrent REQUIRED)
 target_link_directories(Attorney_Online PRIVATE lib)
-target_link_libraries(Attorney_Online PRIVATE Qt5::Core Qt5::Gui Qt5::Network Qt5::Widgets
+target_link_libraries(Attorney_Online PRIVATE Qt5::Core Qt5::Gui Qt5::Network Qt5::Widgets Qt5::Concurrent
     bass bassopus discord-rpc)
 target_compile_definitions(Attorney_Online PRIVATE DISCORD)
 
diff --git a/include/aolayer.h b/include/aolayer.h
index b890715..4d2629b 100644
--- a/include/aolayer.h
+++ b/include/aolayer.h
@@ -148,7 +148,7 @@ private:
 
   // used in populate_vectors
   void load_next_frame();
-  bool exit_loop; //awful solution but i'm not fucking using QThread
+  std::atomic_bool exit_loop; //awful solution but i'm not fucking using QThread
   QFuture<void> frame_loader;
   QMutex mutex;
   QWaitCondition frameAdded;
diff --git a/src/aolayer.cpp b/src/aolayer.cpp
index 1587d28..08ee392 100644
--- a/src/aolayer.cpp
+++ b/src/aolayer.cpp
@@ -4,6 +4,8 @@
 #include "file_functions.h"
 #include "misc_functions.h"
 
+static QThreadPool *thread_pool;
+
 AOLayer::AOLayer(QWidget *p_parent, AOApplication *p_ao_app) : QLabel(p_parent)
 {
   ao_app = p_ao_app;
@@ -22,6 +24,11 @@ AOLayer::AOLayer(QWidget *p_parent, AOApplication *p_ao_app) : QLabel(p_parent)
   preanim_timer = new QTimer(this);
   preanim_timer->setSingleShot(true);
   connect(preanim_timer, &QTimer::timeout, this, &AOLayer::preanim_done);
+
+  if (!thread_pool) {
+    thread_pool = new QThreadPool(p_ao_app);
+    thread_pool->setMaxThreadCount(8);
+  }
 }
 
 BackgroundLayer::BackgroundLayer(QWidget *p_parent, AOApplication *p_ao_app)
@@ -319,7 +326,7 @@ void AOLayer::start_playback(QString p_image)
     frame = 0;
     continuous = false;
   }
-  frame_loader = QtConcurrent::run(this, &AOLayer::populate_vectors);
+  frame_loader = QtConcurrent::run(thread_pool, this, &AOLayer::populate_vectors);
   last_path = p_image;
   while (movie_frames.size() <= frame) // if we haven't loaded the frame we need yet
     frameAdded.wait(&mutex); // wait for the frame loader to add another frame, then check again
@@ -538,11 +545,11 @@ void AOLayer::movie_ticker()
     else
       frame = 0;
   }
-  mutex.lock();
-  while (frame >= movie_frames.size() && frame < max_frames) { // oops! our frame isn't ready yet
+  {
+    QMutexLocker locker(&mutex);
+    while (frame >= movie_frames.size() && frame < max_frames) // oops! our frame isn't ready yet
       frameAdded.wait(&mutex); // wait for a new frame to be added, then check again
   }
-  mutex.unlock();
 #ifdef DEBUG_MOVIE
   qDebug() << "[AOLayer::movie_ticker] Frame:" << frame << "Delay:" << movie_delays[frame]
            << "Actual time taken from last frame:" << actual_time.restart();
@@ -552,7 +559,7 @@ void AOLayer::movie_ticker()
 }
 
 void AOLayer::populate_vectors() {
-    while (movie_frames.size() < max_frames && !exit_loop) {
+    while (!exit_loop && movie_frames.size() < max_frames) {
         load_next_frame();
 #ifdef DEBUG_MOVIE
         qDebug() << "[AOLayer::populate_vectors] Loaded frame" << movie_frames.size();
@@ -562,12 +569,12 @@ void AOLayer::populate_vectors() {
 }
 
 void AOLayer::load_next_frame() {
-    //QMutexLocker locker(&mutex);
-    mutex.lock();
+  {
+    QMutexLocker locker(&mutex);
     movie_frames.append(this->get_pixmap(m_reader.read()));
     movie_delays.append(m_reader.nextImageDelay());
-    mutex.unlock();
-    frameAdded.wakeAll();
+  }
+  frameAdded.wakeAll();
 }
 
 void CharLayer::preanim_done()