From 54565060fda57254e143c18b2c74ff7212e9e1f4 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Thu, 4 Oct 2012 13:50:41 -0700
Subject: [PATCH] I'm becoming more and more convinced that the application
 should never use XRandR, and it's the window manager's responsibility to
 track and manage display modes for fullscreen windows. Because it's so
 broken, I'm going to disable XRandR by default.  You can still enable it via
 environment variable or application hint (SDL_HINT_VIDEO_X11_XRANDR)

---
 include/SDL_hints.h          |  2 +-
 src/video/x11/SDL_x11modes.c | 21 ++++++++++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index aff3602ba..d882d3af4 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -148,7 +148,7 @@ extern "C" {
  *    "0"       - Disable XRandR
  *    "1"       - Enable XRandR
  *
- *  By default SDL will use XRandR if it is available.
+ *  By default SDL will not use XRandR because of window manager issues.
  */
 #define SDL_HINT_VIDEO_X11_XRANDR           "SDL_VIDEO_X11_XRANDR"
 
diff --git a/src/video/x11/SDL_x11modes.c b/src/video/x11/SDL_x11modes.c
index 49c3451fc..4715476b5 100644
--- a/src/video/x11/SDL_x11modes.c
+++ b/src/video/x11/SDL_x11modes.c
@@ -25,7 +25,17 @@
 #include "SDL_hints.h"
 #include "SDL_x11video.h"
 
-/*#define X11MODES_DEBUG*/
+#define X11MODES_DEBUG
+
+/* I'm becoming more and more convinced that the application should never use XRandR,
+ * and it's the window manager's responsibility to track and manage display modes for
+ * fullscreen windows.  Right now XRandR is completely broken with respect to window
+ * manager behavior on every window manager that I can find.  For example, on Unity 3D
+ * if you show a fullscreen window while the resolution is changing (within ~250 ms)
+ * your window will retain the fullscreen state hint but be decorated and windowed.
+*/
+#define XRANDR_DISABLED_BY_DEFAULT
+
 
 static int
 get_visualinfo(Display * display, int screen, XVisualInfo * vinfo)
@@ -190,12 +200,21 @@ CheckXRandR(Display * display, int *major, int *minor)
 
     /* Allow environment override */
     env = SDL_GetHint(SDL_HINT_VIDEO_X11_XRANDR);
+#ifdef XRANDR_DISABLED_BY_DEFAULT
+    if (!env || !SDL_atoi(env)) {
+#ifdef X11MODES_DEBUG
+        printf("XRandR disabled by default due to window manager issues\n");
+#endif
+        return SDL_FALSE;
+    }
+#else
     if (env && !SDL_atoi(env)) {
 #ifdef X11MODES_DEBUG
         printf("XRandR disabled due to hint\n");
 #endif
         return SDL_FALSE;
     }
+#endif /* XRANDR_ENABLED_BY_DEFAULT */
 
     if (!SDL_X11_HAVE_XRANDR) {
 #ifdef X11MODES_DEBUG