From 68320629de4683c66cda1dc2da5e04e83d896ee7 Mon Sep 17 00:00:00 2001
From: MihailRis <mexaruc@gmail.com>
Date: Fri, 5 Apr 2024 20:36:11 +0300
Subject: [PATCH] ThreadPool stand-alone results

---
 src/files/WorldConverter.cpp           |  6 +-----
 src/files/WorldConverter.h             |  3 +--
 src/graphics/render/ChunksRenderer.cpp |  1 +
 src/util/ThreadPool.h                  | 28 ++++++++++++++++++++------
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/files/WorldConverter.cpp b/src/files/WorldConverter.cpp
index 9588aad0..d64953aa 100644
--- a/src/files/WorldConverter.cpp
+++ b/src/files/WorldConverter.cpp
@@ -37,10 +37,6 @@ WorldConverter::~WorldConverter() {
     delete wfile;
 }
 
-bool WorldConverter::hasNext() const {
-    return !tasks.empty();
-}
-
 void WorldConverter::convertRegion(fs::path file) {
     int x, z;
     std::string name = file.stem().string();
@@ -72,7 +68,7 @@ void WorldConverter::convertPlayer(fs::path file) {
 }
 
 void WorldConverter::convertNext() {
-    if (!hasNext()) {
+    if (tasks.empty()) {
         throw std::runtime_error("no more regions to convert");
     }
     convert_task task = tasks.front();
diff --git a/src/files/WorldConverter.h b/src/files/WorldConverter.h
index 0a34a9e5..feabda2f 100644
--- a/src/files/WorldConverter.h
+++ b/src/files/WorldConverter.h
@@ -41,7 +41,6 @@ public:
     );
     ~WorldConverter();
 
-    bool hasNext() const;
     void convertNext();
 
     void setOnComplete(runnable callback) {
@@ -50,7 +49,7 @@ public:
 
     void update() override {
         convertNext();
-        if (onComplete && !hasNext()) {
+        if (onComplete && tasks.empty()) {
             onComplete();
         }
     }
diff --git a/src/graphics/render/ChunksRenderer.cpp b/src/graphics/render/ChunksRenderer.cpp
index eed947ec..de272a36 100644
--- a/src/graphics/render/ChunksRenderer.cpp
+++ b/src/graphics/render/ChunksRenderer.cpp
@@ -45,6 +45,7 @@ ChunksRenderer::ChunksRenderer(
             inwork.erase(mesh.key);
         })
 {
+    threadPool.setStandaloneResults(false);
     renderer = std::make_unique<BlocksRenderer>(
         RENDERER_CAPACITY, level->content, cache, settings
     );
diff --git a/src/util/ThreadPool.h b/src/util/ThreadPool.h
index 646e65a1..4f5bed77 100644
--- a/src/util/ThreadPool.h
+++ b/src/util/ThreadPool.h
@@ -46,6 +46,7 @@ class ThreadPool : public Task {
     std::atomic<int> busyWorkers = 0;
     std::atomic<uint> jobsDone = 0;
     bool working = true;
+    bool standaloneResults = true;
 
     void threadLoop(int index, std::shared_ptr<Worker<T, R>> worker) {
         std::condition_variable variable;
@@ -71,10 +72,12 @@ class ThreadPool : public Task {
                 {
                     std::lock_guard<std::mutex> lock(resultsMutex);
                     results.push(ThreadPoolResult<R> {variable, index, locked, result});
-                    locked = true;
+                    if (!standaloneResults) {
+                        locked = true;
+                    }
                     busyWorkers--;
                 }
-                {
+                if (!standaloneResults){
                     std::unique_lock<std::mutex> lock(mutex);
                     variable.wait(lock, [&] {
                         return !working || !locked;
@@ -119,8 +122,10 @@ public:
             while (!results.empty()) {
                 ThreadPoolResult<R> entry = results.front();
                 results.pop();
-                entry.locked = false;
-                entry.variable.notify_all();
+                if (!standaloneResults) {
+                    entry.locked = false;
+                    entry.variable.notify_all();
+                }
             }
         }
 
@@ -138,8 +143,10 @@ public:
 
             resultConsumer(entry.entry);
 
-            entry.locked = false;
-            entry.variable.notify_all();
+            if (!standaloneResults) {
+                entry.locked = false;
+                entry.variable.notify_all();
+            }
         }
 
         if (onComplete && busyWorkers == 0) {
@@ -158,10 +165,19 @@ public:
         jobsMutexCondition.notify_one();
     }
 
+    /// @brief If false: worker will be blocked until it's result performed 
+    void setStandaloneResults(bool flag) {
+        standaloneResults = flag;
+    }
+
+    /// @brief onJobFailed called on exception thrown in worker thread.
+    /// Use engine.postRunnable when calling terminate()
     void setOnJobFailed(consumer<T&> callback) {
         this->onJobFailed = callback;
     }
 
+    /// @brief onComplete called in ThreadPool.update() when all jobs done 
+    /// if ThreadPool was not terminated
     void setOnComplete(runnable callback) {
         this->onComplete = callback;
     }