3 files changed, 33 insertions, 0 deletions
diff --git a/indra/llwindow/llwindow.h b/indra/llwindow/llwindow.h
index aff9334cb6..5bb538f892 100644
--- a/indra/llwindow/llwindow.h
+++ b/indra/llwindow/llwindow.h
@@ -34,6 +34,8 @@
 #include "llinstancetracker.h"
 #include "llsd.h"
 
+#include "../llrender/llglheaders.h"
+
 class LLSplashScreen;
 class LLPreeditor;
 class LLWindowCallbacks;
@@ -243,6 +245,8 @@ protected:
     S32         mMinWindowHeight;
     S32         mRefreshRate;
 
+    GLsync      swapFense;
+
     // Handle a UTF-16 encoding unit received from keyboard.
     // Converting the series of UTF-16 encoding units to UTF-32 data,
     // this method passes the resulting UTF-32 data to mCallback's
diff --git a/indra/llwindow/llwindowmacosx.cpp b/indra/llwindow/llwindowmacosx.cpp
index 453905b19b..1b8ab27f23 100644
--- a/indra/llwindow/llwindowmacosx.cpp
+++ b/indra/llwindow/llwindowmacosx.cpp
@@ -38,6 +38,8 @@
 #include "lldir.h"
 #include "indra_constants.h"
 
+#include "../newview/llviewercontrol.h"
+
 #include <OpenGL/OpenGL.h>
 #include <Carbon/Carbon.h>
 #include <CoreServices/CoreServices.h>
@@ -50,6 +52,8 @@
 #include <IOKit/hid/IOHIDLib.h>
 #include <IOKit/usb/IOUSBLib.h>
 
+
+
 extern BOOL gDebugWindowProc;
 BOOL gHiDPISupport = TRUE;
 
@@ -1009,6 +1013,19 @@ BOOL LLWindowMacOSX::setSizeImpl(const LLCoordWindow size)
 void LLWindowMacOSX::swapBuffers()
 {
     CGLFlushDrawable(mContext);
+
+    U32 mode = gSavedSettings.getU32("MPVBufferOptiMode");
+    if (mode == 0)
+    {
+        if(gGLManager.mIsApple) mode = 2;
+        else mode = 1;
+    }
+    if (mode > 2)
+    {
+        glClientWaitSync(swapFense, GL_SYNC_FLUSH_COMMANDS_BIT, GL_TIMEOUT_IGNORED);
+        glDeleteSync(swapFense);
+        swapFense = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+    }
 }
 
 void LLWindowMacOSX::restoreGLContext()
diff --git a/indra/llwindow/llwindowsdl.cpp b/indra/llwindow/llwindowsdl.cpp
index 98484419f9..110a28ca48 100644
--- a/indra/llwindow/llwindowsdl.cpp
+++ b/indra/llwindow/llwindowsdl.cpp
@@ -1098,6 +1098,18 @@ void LLWindowSDL::swapBuffers()
     if (mWindow)
     {
         SDL_GL_SwapWindow(mWindow);
+        U32 mode = gSavedSettings.getU32("MPVBuffMapMode");
+        if (mode == 0)
+        {
+            if(gGLManager.mIsApple) mode = 2;
+            else mode = 1;
+        }
+        if (mode > 2)
+        {
+            glClientWaitSync(swapFense, GL_SYNC_FLUSH_COMMANDS_BIT, GL_TIMEOUT_IGNORED);
+            glDeleteSync(swapFense);
+            swapFense = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+        }
     }
 }