diff --git a/engine/ref_api.h b/engine/ref_api.h
index 2a460582..15d6c477 100644
--- a/engine/ref_api.h
+++ b/engine/ref_api.h
@@ -447,6 +447,7 @@ typedef struct ref_interface_s
 	void (*GL_InitExtensions)( void );
 	void (*GL_ClearExtensions)( void );
 
+	// scene rendering
 	void (*R_BeginFrame)( qboolean clearScene );
 	void (*R_RenderScene)( void );
 	void (*R_EndFrame)( void );
@@ -461,7 +462,8 @@ typedef struct ref_interface_s
 
 	qboolean (*R_AddEntity)( struct cl_entity_s *clent, int type );
 	void (*CL_AddCustomBeam)( cl_entity_t *pEnvBeam );
-	void		(*R_ProcessEntData)( qboolean allocate, cl_entity_t *entities, unsigned int max_entities );
+	void (*R_ProcessEntData)( qboolean allocate, cl_entity_t *entities, unsigned int max_entities );
+	void (*R_Flush)( unsigned int flush_flags );
 
 	// debug
 	void (*R_ShowTextures)( void );
diff --git a/ref/gl/gl_context.c b/ref/gl/gl_context.c
index b9f468aa..5b388511 100644
--- a/ref/gl/gl_context.c
+++ b/ref/gl/gl_context.c
@@ -316,6 +316,11 @@ void R_ProcessEntData( qboolean allocate, cl_entity_t *entities, unsigned int ma
 		gEngfuncs.drawFuncs->R_ProcessEntData( allocate );
 }
 
+static void GAME_EXPORT R_Flush( unsigned int flags )
+{
+	// stub
+}
+
 qboolean R_SetDisplayTransform( ref_screen_rotation_t rotate, int offset_x, int offset_y, float scale_x, float scale_y )
 {
 	qboolean ret = true;
@@ -380,6 +385,7 @@ ref_interface_t gReffuncs =
 	R_AddEntity,
 	CL_AddCustomBeam,
 	R_ProcessEntData,
+	R_Flush,
 
 	R_ShowTextures,
 
diff --git a/ref/soft/r_context.c b/ref/soft/r_context.c
index 016b5285..69fcdace 100644
--- a/ref/soft/r_context.c
+++ b/ref/soft/r_context.c
@@ -279,6 +279,11 @@ void GAME_EXPORT R_ProcessEntData( qboolean allocate, cl_entity_t *entities, uns
 	tr.max_entities = max_entities;
 }
 
+static void GAME_EXPORT R_Flush( unsigned int flags )
+{
+	// stub
+}
+
 // stubs
 
 void GAME_EXPORT GL_SetTexCoordArrayMode( uint mode )
@@ -426,6 +431,7 @@ ref_interface_t gReffuncs =
 	R_AddEntity,
 	CL_AddCustomBeam,
 	R_ProcessEntData,
+	R_Flush,
 
 	R_ShowTextures,