From e52def47371f3934ee57a98717e3d13237accb4b Mon Sep 17 00:00:00 2001
From: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
Date: Tue, 24 Jul 2012 10:58:32 +0200
Subject: [PATCH] utils: fix gl_create_context() with parent context set.

If GLX window was created from a foreign Display, then that same Display shall
be used for subsequent glXMakeCurrent(). This means that gl_create_context()
will now use the same Display that the parent, if available.

This fixes cluttersink with the Intel GenX VA driver.
---
 gst-libs/gst/vaapi/gstvaapiutils_glx.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/gst-libs/gst/vaapi/gstvaapiutils_glx.c b/gst-libs/gst/vaapi/gstvaapiutils_glx.c
index bf7c358..3821181 100644
--- a/gst-libs/gst/vaapi/gstvaapiutils_glx.c
+++ b/gst-libs/gst/vaapi/gstvaapiutils_glx.c
@@ -309,8 +309,15 @@ gl_create_context(Display *dpy, int screen, GLContextState *parent)
     if (!cs)
         goto error;
 
-    cs->display         = dpy;
-    cs->window          = parent ? parent->window : None;
+    if (parent) {
+        cs->display     = parent->display;
+        cs->window      = parent->window;
+        screen          = DefaultScreen(parent->display);
+    }
+    else {
+        cs->display     = dpy;
+        cs->window      = None;
+    }
     cs->visual          = NULL;
     cs->context         = NULL;
     cs->swapped_buffers = FALSE;
@@ -327,14 +334,14 @@ gl_create_context(Display *dpy, int screen, GLContextState *parent)
         if (fbconfig_id == GLX_DONT_CARE)
             goto choose_fbconfig;
 
-        fbconfigs = glXGetFBConfigs(dpy, screen, &n_fbconfigs);
+        fbconfigs = glXGetFBConfigs(parent->display, screen, &n_fbconfigs);
         if (!fbconfigs)
             goto error;
 
         /* Find out a GLXFBConfig compatible with the parent context */
         for (n = 0; n < n_fbconfigs; n++) {
             status = glXGetFBConfigAttrib(
-                dpy,
+                parent->display,
                 fbconfigs[n],
                 GLX_FBCONFIG_ID, &val
             );
@@ -347,7 +354,7 @@ gl_create_context(Display *dpy, int screen, GLContextState *parent)
     else {
     choose_fbconfig:
         fbconfigs = glXChooseFBConfig(
-            dpy,
+            cs->display,
             screen,
             fbconfig_attrs, &n_fbconfigs
         );
@@ -358,9 +365,9 @@ gl_create_context(Display *dpy, int screen, GLContextState *parent)
         n = 0;
     }
 
-    cs->visual  = glXGetVisualFromFBConfig(dpy, fbconfigs[n]);
+    cs->visual  = glXGetVisualFromFBConfig(cs->display, fbconfigs[n]);
     cs->context = glXCreateNewContext(
-        dpy,
+        cs->display,
         fbconfigs[n],
         GLX_RGBA_TYPE,
         parent ? parent->context : NULL,
-- 
2.7.4