From f9cdd49d2ec6f191db1d91d0b3cd0bfedb31b5e5 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Mon, 20 Aug 2018 22:25:19 -0700
Subject: [PATCH] Add settings option to disable V-sync for lowest possible
 latency on Windows

---
 app/gui/SettingsView.qml              | 27 ++++++++++++++++++++-------
 app/settings/streamingpreferences.cpp |  3 +++
 app/settings/streamingpreferences.h   |  3 +++
 app/streaming/session.cpp             |  2 +-
 4 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/app/gui/SettingsView.qml b/app/gui/SettingsView.qml
index a2300791..508a3215 100644
--- a/app/gui/SettingsView.qml
+++ b/app/gui/SettingsView.qml
@@ -230,13 +230,26 @@ ScrollView {
                     }
                 }
 
-                CheckBox {
-                    id: fullScreenCheck
-                    text: "<font color=\"white\">Full-screen</font>"
-                    font.pointSize:  12
-                    checked: prefs.fullScreen
-                    onCheckedChanged: {
-                        prefs.fullScreen = checked
+                Row {
+                    CheckBox {
+                        id: fullScreenCheck
+                        text: "<font color=\"white\">Full-screen</font>"
+                        font.pointSize:  12
+                        checked: prefs.fullScreen
+                        onCheckedChanged: {
+                            prefs.fullScreen = checked
+                        }
+                    }
+
+                    CheckBox {
+                        id: vsyncCheck
+                        text: "<font color=\"white\">Enable V-Sync</font>"
+                        font.pointSize:  12
+                        visible: fullScreenCheck.checked
+                        checked: prefs.enableVsync
+                        onCheckedChanged: {
+                            prefs.enableVsync = checked
+                        }
                     }
                 }
             }
diff --git a/app/settings/streamingpreferences.cpp b/app/settings/streamingpreferences.cpp
index ae6bdb7c..8cbf313c 100644
--- a/app/settings/streamingpreferences.cpp
+++ b/app/settings/streamingpreferences.cpp
@@ -9,6 +9,7 @@
 #define SER_FPS "fps"
 #define SER_BITRATE "bitrate"
 #define SER_FULLSCREEN "fullscreen"
+#define SER_VSYNC "vsync"
 #define SER_GAMEOPTS "gameopts"
 #define SER_HOSTAUDIO "hostaudio"
 #define SER_MULTICONT "multicontroller"
@@ -30,6 +31,7 @@ void StreamingPreferences::reload()
     fps = settings.value(SER_FPS, 60).toInt();
     bitrateKbps = settings.value(SER_BITRATE, getDefaultBitrate(width, height, fps)).toInt();
     fullScreen = settings.value(SER_FULLSCREEN, true).toBool();
+    enableVsync = settings.value(SER_VSYNC, true).toBool();
     gameOptimizations = settings.value(SER_GAMEOPTS, true).toBool();
     playAudioOnHost = settings.value(SER_HOSTAUDIO, false).toBool();
     multiController = settings.value(SER_MULTICONT, true).toBool();
@@ -50,6 +52,7 @@ void StreamingPreferences::save()
     settings.setValue(SER_FPS, fps);
     settings.setValue(SER_BITRATE, bitrateKbps);
     settings.setValue(SER_FULLSCREEN, fullScreen);
+    settings.setValue(SER_VSYNC, enableVsync);
     settings.setValue(SER_GAMEOPTS, gameOptimizations);
     settings.setValue(SER_HOSTAUDIO, playAudioOnHost);
     settings.setValue(SER_MULTICONT, multiController);
diff --git a/app/settings/streamingpreferences.h b/app/settings/streamingpreferences.h
index 9aea8722..b06020d2 100644
--- a/app/settings/streamingpreferences.h
+++ b/app/settings/streamingpreferences.h
@@ -55,6 +55,7 @@ public:
     Q_PROPERTY(int fps MEMBER fps NOTIFY displayModeChanged)
     Q_PROPERTY(int bitrateKbps MEMBER bitrateKbps NOTIFY bitrateChanged)
     Q_PROPERTY(bool fullScreen MEMBER fullScreen NOTIFY fullScreenChanged)
+    Q_PROPERTY(bool enableVsync MEMBER enableVsync NOTIFY enableVsyncChanged)
     Q_PROPERTY(bool gameOptimizations MEMBER gameOptimizations NOTIFY gameOptimizationsChanged)
     Q_PROPERTY(bool playAudioOnHost MEMBER playAudioOnHost NOTIFY playAudioOnHostChanged)
     Q_PROPERTY(bool multiController MEMBER multiController NOTIFY multiControllerChanged)
@@ -68,6 +69,7 @@ public:
     int fps;
     int bitrateKbps;
     bool fullScreen;
+    bool enableVsync;
     bool gameOptimizations;
     bool playAudioOnHost;
     bool multiController;
@@ -79,6 +81,7 @@ signals:
     void displayModeChanged();
     void bitrateChanged();
     void fullScreenChanged();
+    void enableVsyncChanged();
     void gameOptimizationsChanged();
     void playAudioOnHostChanged();
     void multiControllerChanged();
diff --git a/app/streaming/session.cpp b/app/streaming/session.cpp
index cf69b5d3..8ff6dffa 100644
--- a/app/streaming/session.cpp
+++ b/app/streaming/session.cpp
@@ -834,7 +834,7 @@ void Session::exec()
             if (!chooseDecoder(m_Preferences.videoDecoderSelection,
                                m_Window, m_ActiveVideoFormat, m_ActiveVideoWidth,
                                m_ActiveVideoHeight, m_ActiveVideoFrameRate,
-                               true, // TODO: User configuration for V-sync
+                               m_Preferences.enableVsync,
                                s_ActiveSession->m_VideoDecoder)) {
                 SDL_AtomicUnlock(&m_DecoderLock);
                 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,