diff --git a/src/gl/renderer/gl_renderer.h b/src/gl/renderer/gl_renderer.h
index eeaa631d..6cd50e4f 100644
--- a/src/gl/renderer/gl_renderer.h
+++ b/src/gl/renderer/gl_renderer.h
@@ -89,7 +89,7 @@ public:
 	void SetViewArea();
 	void ResetViewport();
 	void SetViewport(GL_IRECT *bounds);
-	sector_t *RenderViewpoint (AActor * camera, GL_IRECT * bounds, float fov, float ratio, float fovratio, bool mainview);
+	sector_t *RenderViewpoint (AActor * camera, GL_IRECT * bounds, float fov, float ratio, float fovratio, bool mainview, bool toscreen);
 	void RenderView(player_t *player);
 	void SetCameraPos(fixed_t viewx, fixed_t viewy, fixed_t viewz, angle_t viewangle);
 	void SetupView(fixed_t viewx, fixed_t viewy, fixed_t viewz, angle_t viewangle, bool mirror, bool planemirror);
@@ -99,7 +99,7 @@ public:
 	void CreateScene();
 	void RenderScene(int recursion);
 	void RenderTranslucent();
-	void DrawScene();
+	void DrawScene(bool toscreen = false);
 	void DrawBlend(sector_t * viewsector);
 
 	void DrawPSprite (player_t * player,pspdef_t *psp,fixed_t sx, fixed_t sy, int cm_index, bool hudModelStep);
@@ -131,7 +131,7 @@ public:
 
 	void SetProjection(float fov, float ratio, float fovratio);
 	void SetViewMatrix(bool mirror, bool planemirror);
-	void ProcessScene();
+	void ProcessScene(bool toscreen = false);
 
 	bool StartOffscreen();
 	void EndOffscreen();
diff --git a/src/gl/scene/gl_scene.cpp b/src/gl/scene/gl_scene.cpp
index c8f6ee90..f163abf0 100644
--- a/src/gl/scene/gl_scene.cpp
+++ b/src/gl/scene/gl_scene.cpp
@@ -546,12 +546,22 @@ void FGLRenderer::RenderTranslucent()
 // stencil, z-buffer and the projection matrix intact!
 //
 //-----------------------------------------------------------------------------
+EXTERN_CVAR(Bool, gl_draw_synchronized)
 
-void FGLRenderer::DrawScene()
+void FGLRenderer::DrawScene(bool toscreen)
 {
 	static int recursion=0;
 
 	CreateScene();
+
+	// Up to this point in the main draw call no rendering is performed so we can wait
+	// with swapping the render buffer until now.
+	if (!gl_draw_synchronized && toscreen)
+	{
+		All.Unclock();
+		static_cast<OpenGLFrameBuffer*>(screen)->Swap();
+		All.Clock();
+	}
 	RenderScene(recursion);
 
 	// Handle all portals after rendering the opaque objects but before
@@ -809,13 +819,13 @@ void FGLRenderer::EndDrawScene(sector_t * viewsector)
 //
 //-----------------------------------------------------------------------------
 
-void FGLRenderer::ProcessScene()
+void FGLRenderer::ProcessScene(bool toscreen)
 {
 	FDrawInfo::StartDrawInfo();
 	iter_dlightf = iter_dlight = draw_dlight = draw_dlightf = 0;
 	GLPortal::BeginScene();
 
-	DrawScene();
+	DrawScene(toscreen);
 	FDrawInfo::EndDrawInfo();
 
 }
@@ -869,7 +879,7 @@ void FGLRenderer::SetFixedColormap (player_t *player)
 //
 //-----------------------------------------------------------------------------
 
-sector_t * FGLRenderer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, float fov, float ratio, float fovratio, bool mainview)
+sector_t * FGLRenderer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, float fov, float ratio, float fovratio, bool mainview, bool toscreen)
 {       
 	sector_t * retval;
 	R_SetupFrame (camera);
@@ -904,7 +914,7 @@ sector_t * FGLRenderer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, flo
 	angle_t a1 = GLRenderer->FrustumAngle();
 	clipper.SafeAddClipRange(viewangle+a1, viewangle-a1);
 
-	ProcessScene();
+	ProcessScene(toscreen);
 
 	gl_frameCount++;	// This counter must be increased right before the interpolations are restored.
 	interpolator.RestoreInterpolations ();
@@ -968,7 +978,7 @@ void FGLRenderer::RenderView (player_t* player)
 	TThinkerIterator<ADynamicLight> it(STAT_DLIGHT);
 	GLRenderer->mLightCount = ((it.Next()) != NULL);
 
-	sector_t * viewsector = RenderViewpoint(player->camera, NULL, FieldOfView * 360.0f / FINEANGLES, ratio, fovratio, true);
+	sector_t * viewsector = RenderViewpoint(player->camera, NULL, FieldOfView * 360.0f / FINEANGLES, ratio, fovratio, true, true);
 	EndDrawScene(viewsector);
 
 	All.Unclock();
@@ -996,7 +1006,7 @@ void FGLRenderer::WriteSavePic (player_t *player, FILE *file, int width, int hei
 	GLRenderer->mLightCount = ((it.Next()) != NULL);
 
 	sector_t *viewsector = RenderViewpoint(players[consoleplayer].camera, &bounds, 
-								FieldOfView * 360.0f / FINEANGLES, 1.6f, 1.6f, true);
+								FieldOfView * 360.0f / FINEANGLES, 1.6f, 1.6f, true, false);
 	gl.Disable(GL_STENCIL_TEST);
 	screen->Begin2D(false);
 	DrawBlend(viewsector);
diff --git a/src/gl/system/gl_framebuffer.cpp b/src/gl/system/gl_framebuffer.cpp
index ca5eddc3..8e3869fc 100644
--- a/src/gl/system/gl_framebuffer.cpp
+++ b/src/gl/system/gl_framebuffer.cpp
@@ -88,6 +88,7 @@ OpenGLFrameBuffer::OpenGLFrameBuffer(int width, int height, int bits, int refres
 	gl_GenerateGlobalBrightmapFromColormap();
 	DoSetGamma();
 	needsetgamma = true;
+	swapped = false;
 }
 
 OpenGLFrameBuffer::~OpenGLFrameBuffer()
@@ -168,7 +169,7 @@ void OpenGLFrameBuffer::InitializeState()
 // Updates the screen
 //
 //==========================================================================
-CVAR(Bool, gl_draw_synchronized, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
+CVAR(Bool, gl_draw_sync, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 void OpenGLFrameBuffer::Update()
 {
@@ -190,10 +191,26 @@ void OpenGLFrameBuffer::Update()
 
 		Begin2D(false);
 	}
+	if (gl_draw_sync || !swapped)
+	{
+		Swap();
+	}
+	swapped = false;
+	Unlock();
+}
+
+
+//==========================================================================
+//
+// Swap the buffers
+//
+//==========================================================================
+
+void OpenGLFrameBuffer::Swap()
+{
 	Finish.Reset();
 	Finish.Clock();
-	if (gl_draw_synchronized) gl.Finish();
-	else gl.Flush();
+	gl.Finish();
 	if (needsetgamma) 
 	{
 		DoSetGamma();
@@ -201,8 +218,7 @@ void OpenGLFrameBuffer::Update()
 	}
 	gl.SwapBuffers();
 	Finish.Unclock();
-
-	Unlock();
+	swapped = true;
 }
 
 //===========================================================================
diff --git a/src/gl/system/gl_framebuffer.h b/src/gl/system/gl_framebuffer.h
index 3335ab76..b4a83002 100644
--- a/src/gl/system/gl_framebuffer.h
+++ b/src/gl/system/gl_framebuffer.h
@@ -86,6 +86,7 @@ public:
 	void WipeEndScreen();
 	bool WipeDo(int ticks);
 	void WipeCleanup();
+	void Swap();
 
 
 private:
@@ -96,6 +97,7 @@ private:
 	int translation;
 	bool iscomplex;
 	bool needsetgamma;
+	bool swapped;
 
 	PalEntry SourcePalette[256];
 	BYTE *ScreenshotBuffer;
diff --git a/src/gl/textures/gl_cameratexture.cpp b/src/gl/textures/gl_cameratexture.cpp
index 2d279244..d0fe07f8 100644
--- a/src/gl/textures/gl_cameratexture.cpp
+++ b/src/gl/textures/gl_cameratexture.cpp
@@ -84,7 +84,7 @@ void FCanvasTexture::RenderGLView (AActor *Viewpoint, int FOV)
 	bounds.width=FHardwareTexture::GetTexDimension(gltex->GetWidth(GLUSE_TEXTURE));
 	bounds.height=FHardwareTexture::GetTexDimension(gltex->GetHeight(GLUSE_TEXTURE));
 
-	GLRenderer->RenderViewpoint(Viewpoint, &bounds, FOV, (float)width/height, (float)width/height, false);
+	GLRenderer->RenderViewpoint(Viewpoint, &bounds, FOV, (float)width/height, (float)width/height, false, false);
 
 	if (!usefb)
 	{