fix: ⚡ Reduce delay when setting chaperone

Author: zmerp

alvr/server/cpp/alvr_server/ChaperoneUpdater.cpp

@@ -11,26 +11,34 @@ namespace alvr_chaperone {
 using namespace alvr_chaperone;
 #endif
 
-static std::mutex chaperone_mutex;
+std::mutex chaperone_mutex;
 
-#ifdef __linux__
-vr::HmdMatrix34_t GetRawZeroPose() {
-    vr::HmdMatrix34_t out = {};
+void InitChaperoneClient() {
+#ifndef __APPLE__
     std::unique_lock<std::mutex> lock(chaperone_mutex);
+
     vr::EVRInitError error;
     vr::VR_Init(&error, vr::VRApplication_Utility);
+
     if (error != vr::VRInitError_None) {
-        Warn("Failed to init OpenVR client to get raw zero pose! Error: %d", error);
-        return out;
+        Warn("Failed to init OpenVR client to update Chaperone boundary! Error: %d", error);
+        return;
     }
-    out = vr::VRSystem()->GetRawZeroPoseToStandingAbsoluteTrackingPose();
-    vr::VR_Shutdown();
-    return out;
+#endif
 }
+
+void ShutdownChaperoneClient() {
+#ifndef __APPLE__
+    std::unique_lock<std::mutex> lock(chaperone_mutex);
+
+    vr::VR_Shutdown();
 #endif
+}
 
-void SetChaperone(float areaWidth, float areaHeight) {
+void SetChaperoneArea(float areaWidth, float areaHeight) {
 #ifndef __APPLE__
+    std::unique_lock<std::mutex> lock(chaperone_mutex);
+
     const vr::HmdMatrix34_t MATRIX_IDENTITY = {
         {{1.0, 0.0, 0.0, 0.0}, {0.0, 1.0, 0.0, 0.0}, {0.0, 0.0, 1.0, 0.0}}};
 
@@ -45,16 +53,6 @@ void SetChaperone(float areaWidth, float areaHeight) {
     perimeterPoints[3][0] = 1.0f * areaWidth;
     perimeterPoints[3][1] = -1.0f * areaHeight;
 
-    std::unique_lock<std::mutex> lock(chaperone_mutex);
-
-    vr::EVRInitError error;
-    vr::VR_Init(&error, vr::VRApplication_Utility);
-
-    if (error != vr::VRInitError_None) {
-        Warn("Failed to init OpenVR client to update Chaperone boundary! Error: %d", error);
-        return;
-    }
-
     vr::VRChaperoneSetup()->RoomSetupStarting();
     vr::VRChaperoneSetup()->SetWorkingPerimeter(
         reinterpret_cast<vr::HmdVector2_t *>(perimeterPoints), 4);
@@ -66,7 +64,21 @@ void SetChaperone(float areaWidth, float areaHeight) {
     // Hide SteamVR Chaperone
     vr::VRSettings()->SetFloat(
         vr::k_pch_CollisionBounds_Section, vr::k_pch_CollisionBounds_FadeDistance_Float, 0.0f);
+#endif
+}
 
+#ifdef __linux__
+vr::HmdMatrix34_t GetRawZeroPose() {
+    vr::HmdMatrix34_t out = {};
+    std::unique_lock<std::mutex> lock(chaperone_mutex);
+    vr::EVRInitError error;
+    vr::VR_Init(&error, vr::VRApplication_Utility);
+    if (error != vr::VRInitError_None) {
+        Warn("Failed to init OpenVR client to get raw zero pose! Error: %d", error);
+        return out;
+    }
+    out = vr::VRSystem()->GetRawZeroPoseToStandingAbsoluteTrackingPose();
     vr::VR_Shutdown();
-#endif
-}
+    return out;
+}
+#endif

alvr/server/cpp/alvr_server/bindings.h

@@ -142,11 +142,14 @@ extern "C" void ShutdownSteamvr();
 
 extern "C" void SetOpenvrProperty(unsigned long long deviceID, FfiOpenvrProperty prop);
 extern "C" void RegisterButton(unsigned long long buttonID);
-extern "C" void SetChaperone(float areaWidth, float areaHeight);
 extern "C" void SetViewsConfig(FfiViewsConfig config);
 extern "C" void SetBattery(unsigned long long deviceID, float gauge_value, bool is_plugged);
 extern "C" void SetButton(unsigned long long buttonID, FfiButtonValue value);
 
+extern "C" void InitChaperoneClient();
+extern "C" void ShutdownChaperoneClient();
+extern "C" void SetChaperoneArea(float areaWidth, float areaHeight);
+
 extern "C" void CaptureFrame();
 
 // NalParsing.cpp

alvr/server/src/connection.rs

@@ -925,6 +925,8 @@ fn try_connect(mut client_ips: HashMap<IpAddr, String>) -> ConResult {
         let control_sender = Arc::clone(&control_sender);
         let client_hostname = client_hostname.clone();
         move || {
+            unsafe { crate::InitChaperoneClient() };
+
             let mut disconnection_deadline = Instant::now() + KEEPALIVE_TIMEOUT;
             while IS_STREAMING.value() {
                 let packet = match control_receiver.recv(STREAMING_RECV_TIMEOUT) {
@@ -954,7 +956,7 @@ fn try_connect(mut client_ips: HashMap<IpAddr, String>) -> ConResult {
                             );
 
                             let area = packet.unwrap_or(Vec2::new(2.0, 2.0));
-                            unsafe { crate::SetChaperone(area.x, area.y) };
+                            unsafe { crate::SetChaperoneArea(area.x, area.y) };
                         }
                     }
                     ClientControlPacket::RequestIdr => {
@@ -1059,6 +1061,7 @@ fn try_connect(mut client_ips: HashMap<IpAddr, String>) -> ConResult {
 
                 disconnection_deadline = Instant::now() + KEEPALIVE_TIMEOUT;
             }
+            unsafe { crate::ShutdownChaperoneClient() };
 
             SERVER_DATA_MANAGER.write().update_client_list(
                 client_hostname,

alvr/server/src/lib.rs

@@ -358,7 +358,11 @@ pub unsafe extern "C" fn HmdDriverFactory(
             if set_default_chap {
                 // call this when inside a new thread. Calling this on the parent thread will crash
                 // SteamVR
-                unsafe { SetChaperone(2.0, 2.0) };
+                unsafe {
+                    InitChaperoneClient();
+                    SetChaperoneArea(2.0, 2.0);
+                    ShutdownChaperoneClient();
+                }
             }
 
             connection::handshake_loop();