From 3f531bbf98da5ad751dce1220c5c5fdf35f86c92 Mon Sep 17 00:00:00 2001
From: ShadelessFox <yanuari.channel@gmail.com>
Date: Mon, 4 Nov 2024 17:10:18 +0100
Subject: [PATCH] Use high-resolution timer for a better frame time

---
 CMakeLists.txt        |  4 ++++
 src/util/platform.cpp | 36 +++++++++++++++++++++++++++++++-----
 src/util/platform.hpp |  2 ++
 src/window/Window.cpp | 15 ++++++++++-----
 4 files changed, 47 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5a5e839c..f465fcb3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -70,6 +70,10 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -no-pie -lstdc++fs")
 endif()
 
+if (WIN32)
+    target_link_libraries(${PROJECT_NAME} VoxelEngineSrc winmm)
+endif()
+
 target_link_libraries(${PROJECT_NAME} VoxelEngineSrc ${CMAKE_DL_LIBS})
 
 file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/res DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
diff --git a/src/util/platform.cpp b/src/util/platform.cpp
index 6bc3b343..cf16691a 100644
--- a/src/util/platform.cpp
+++ b/src/util/platform.cpp
@@ -5,9 +5,10 @@
 #include <iomanip>
 #include <iostream>
 #include <sstream>
+#include <thread>
 
-#include "typedefs.hpp"
 #include "stringutil.hpp"
+#include "typedefs.hpp"
 
 #ifdef _WIN32
 #include <Windows.h>
@@ -34,6 +35,27 @@ std::string platform::detect_locale() {
         .replace(2, 1, "_")
         .substr(0, 5);
 }
+
+void platform::sleep(size_t millis) {
+    // Uses implementation from the SFML library
+    // https://github.com/SFML/SFML/blob/master/src/SFML/System/Win32/SleepImpl.cpp
+
+    // Get the minimum supported timer resolution on this system
+    static const UINT periodMin = []{
+        TIMECAPS tc;
+        timeGetDevCaps(&tc, sizeof(TIMECAPS));
+        return tc.wPeriodMin;
+    }();
+
+    // Set the timer resolution to the minimum for the Sleep call
+    timeBeginPeriod(periodMin);
+
+    // Wait...
+    Sleep(static_cast<DWORD>(millis));
+
+    // Reset the timer resolution back to the system default
+    timeEndPeriod(periodMin);
+}
 #else
 
 void platform::configure_encoding() {
@@ -47,6 +69,10 @@ std::string platform::detect_locale() {
 
     return preferredLocaleName.substr(0, 5);
 }
+
+void platform::sleep(size_t millis) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(millis));
+}
 #endif
 
 void platform::open_folder(const std::filesystem::path& folder) {
@@ -54,11 +80,11 @@ void platform::open_folder(const std::filesystem::path& folder) {
         return;
     }
 #ifdef __APPLE__
-    auto cmd = "open "+util::quote(folder.u8string());
+    auto cmd = "open " + util::quote(folder.u8string());
 #elif defined(_WIN32)
-    auto cmd = "start explorer "+util::quote(folder.u8string());
+    auto cmd = "start explorer " + util::quote(folder.u8string());
 #else
-    auto cmd = "xdg-open "+util::quote(folder.u8string());
+    auto cmd = "xdg-open " + util::quote(folder.u8string());
 #endif
     system(cmd.c_str());
-}
+}
\ No newline at end of file
diff --git a/src/util/platform.hpp b/src/util/platform.hpp
index b6e8bde9..1283bcfe 100644
--- a/src/util/platform.hpp
+++ b/src/util/platform.hpp
@@ -10,4 +10,6 @@ namespace platform {
     /// @brief Open folder using system file manager asynchronously
     /// @param folder target folder
     void open_folder(const std::filesystem::path& folder);
+    /// Makes the current thread sleep for the specified amount of milliseconds.
+    void sleep(size_t millis);
 }
diff --git a/src/window/Window.cpp b/src/window/Window.cpp
index c77f0d4c..2de948a3 100644
--- a/src/window/Window.cpp
+++ b/src/window/Window.cpp
@@ -14,6 +14,8 @@
 #include "util/ObjectsKeeper.hpp"
 #include "Events.hpp"
 
+#include "util/platform.hpp"
+
 static debug::Logger logger("window");
 
 GLFWwindow* Window::window = nullptr;
@@ -357,11 +359,14 @@ bool Window::isFullscreen() {
 void Window::swapBuffers() {
     glfwSwapBuffers(window);
     Window::resetScissor();
-    double currentTime = time();
-    if (framerate > 0 && currentTime - prevSwap < (1.0 / framerate)) {
-        std::this_thread::sleep_for(std::chrono::milliseconds(static_cast<int>(
-            (1.0 / framerate - (currentTime - prevSwap)) * 1000
-        )));
+    if (framerate > 0) {
+        auto elapsedTime = time() - prevSwap;
+        auto frameTime = 1.0 / framerate;
+        if (elapsedTime < frameTime) {
+            platform::sleep(
+                static_cast<size_t>((frameTime - elapsedTime) * 1000)
+            );
+        }
     }
     prevSwap = time();
 }