From e078838774aa753136601249c8b589d6b99e7367 Mon Sep 17 00:00:00 2001
From: "Owen W. Taylor" <otaylor@fishsoup.net>
Date: Thu, 11 Feb 2016 17:12:09 -0500
Subject: [PATCH] Fix the get_clock_time() without GLX_OML_sync_control

When we don't have GLX_OML_sync_control, we still can set the
frame presentation time, but we always use the system monotonic time,
so return that from get_clock_time().

https://bugzilla.gnome.org/show_bug.cgi?id=779039
---
 cogl/cogl/winsys/cogl-winsys-glx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cogl/cogl/winsys/cogl-winsys-glx.c b/cogl/cogl/winsys/cogl-winsys-glx.c
index 5a2700176..7ad1a3fdf 100644
--- a/cogl/cogl/winsys/cogl-winsys-glx.c
+++ b/cogl/cogl/winsys/cogl-winsys-glx.c
@@ -296,6 +296,9 @@ _cogl_winsys_get_clock_time (CoglContext *context)
 {
   CoglGLXRenderer *glx_renderer = context->display->renderer->winsys;
 
+  if (!glx_renderer->glXWaitForMsc)
+    return get_monotonic_time_ns ();
+
   /* We don't call ensure_ust_type() because we don't have a drawable
    * to work with. cogl_get_clock_time() is documented to only work
    * once a valid, non-zero, timestamp has been retrieved from Cogl.