examples/cogl-x11-tfp.c: Wait for the window to be mapped

Wait for the main window (and hence the window we create within
the main window to redirect) to be mapped and become viewable
before we try to call XCompositeNameWindowPixmap() -
XComposeNameWindowPixmap() produces a BadMatch error on a
non-viewable window.

Reviewed-by: Robert Bragg <robert.bragg@intel.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/examples/cogl-x11-tfp.c b/examples/cogl-x11-tfp.c
index b5803d01..b5859431 100644
--- a/examples/cogl-x11-tfp.c
+++ b/examples/cogl-x11-tfp.c
@@ -139,7 +139,8 @@ main (int argc, char **argv)
                                     DefaultRootWindow (xdpy),
                                     xvisinfo->visual,
                                     AllocNone);
-  mask = CWBorderPixel | CWColormap;
+  xattr.event_mask = StructureNotifyMask;
+  mask = CWBorderPixel | CWColormap | CWEventMask;
 
   xwin = XCreateWindow (xdpy,
                         DefaultRootWindow (xdpy),
@@ -171,6 +172,14 @@ main (int argc, char **argv)
 
   gc = XCreateGC (xdpy, tfp_xwin, 0, NULL);
 
+  while (TRUE)
+    {
+      XWindowEvent (xdpy, xwin, StructureNotifyMask, &xev);
+
+      if (xev.xany.type == MapNotify)
+        break;
+    }
+
   pixmap = XCompositeNameWindowPixmap (xdpy, tfp_xwin);
 
   tfp = cogl_texture_pixmap_x11_new (ctx, pixmap, TRUE, &error);