x11: add --x11-present option

With the recent addition of the libxpresent, it should improve frame
timings for most users. However, there were known cases of bad behavior
(Nvidia) which lead to a construction of a whitelist instead of just
enabling this all the time. Since there's no way to predict whatever
combination of hardware/drivers/etc. may work correctly, just give users
an option to switch the usage of xorg's presentation statistics on/off.
The default value, auto, works like before (basically, Mesa drivers and
no Nvidia are allowed), but now one can force it on/off if needed.

5 files changed, 27 insertions, 3 deletions

diff --git a/DOCS/interface-changes.rst b/DOCS/interface-changes.rst
index 4cd93ab6ab..1c3e6496a9 100644
--- a/DOCS/interface-changes.rst
+++ b/DOCS/interface-changes.rst
@@ -42,6 +42,7 @@ Interface changes
     - `--sub-visibility` no longer has any effect on secondary subtitles
     - add `film-grain` sub-parameter to `format` video filter
     - add experimental `--vo=vaapi-wayland` video output driver
+    - add `--x11-present` for controlling whether to use xorg's present extension
  --- mpv 0.34.0 ---
     - deprecate selecting by card number with `--drm-connector`, add
       `--drm-device` which can be used instead
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index e3aeb4b5bb..59fc79c89e 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -3354,6 +3354,23 @@ Window
 
     ``never`` asks the window manager to never disable the compositor.
 
+``--x11-present=<no|auto|yes>``
+    Whether or not to use presentation statistics from X11's presentation
+    extension (default: ``auto``).
+
+    mpv asks X11 for present events which it then may use for more accurate
+    frame presentation. This only has an effect if ``--video-sync=display-...``
+    is being used.
+
+    The auto option enumerates XRandr providers for autodetection. If amd, radeon,
+    intel, or nouveau (the standard x86 Mesa drivers) is found and nvidia is NOT
+    found, presentation feedback is enabled. Other drivers are not assumed to
+    work, so they are not enabled automatically.
+
+    ``yes`` or ``no`` can still be passed regardless to enable/disable this
+    mechanism in case there is good/bad behavior with whatever your combination
+    of hardware/drivers/etc. happens to be.
+
 
 Disc Devices
 ------------
diff --git a/options/options.c b/options/options.c
index 6d38af53b4..0b1c58d9a6 100644
--- a/options/options.c
+++ b/options/options.c
@@ -175,6 +175,8 @@ static const m_option_t mp_vo_opt_list[] = {
     {"x11-netwm", OPT_CHOICE(x11_netwm, {"auto", 0}, {"no", -1}, {"yes", 1})},
     {"x11-bypass-compositor", OPT_CHOICE(x11_bypass_compositor,
         {"no", 0}, {"yes", 1}, {"fs-only", 2}, {"never", 3})},
+    {"x11-present", OPT_CHOICE(x11_present,
+        {"no", 0}, {"auto", 1}, {"yes", 2})},
 #endif
 #if HAVE_WIN32_DESKTOP
     {"vo-mmcss-profile", OPT_STRING(mmcss_profile)},
@@ -212,6 +214,7 @@ const struct m_sub_options vo_sub_opts = {
         .WinID = -1,
         .window_scale = 1.0,
         .x11_bypass_compositor = 2,
+        .x11_present = 1,
         .mmcss_profile = "Playback",
         .ontop_level = -1,
         .timing_offset = 0.050,
diff --git a/options/options.h b/options/options.h
index 4eb5ef07c7..f38f3b6bfb 100644
--- a/options/options.h
+++ b/options/options.h
@@ -29,6 +29,7 @@ typedef struct mp_vo_opts {
     char *appid;
     int x11_netwm;
     int x11_bypass_compositor;
+    int x11_present;
     int native_keyrepeat;
 
     float panscan;
diff --git a/video/out/x11_common.c b/video/out/x11_common.c
index f041d594ec..054557189f 100644
--- a/video/out/x11_common.c
+++ b/video/out/x11_common.c
@@ -1286,11 +1286,13 @@ void vo_x11_check_events(struct vo *vo)
             break;
         case GenericEvent: {
             XGenericEventCookie *cookie = (XGenericEventCookie *)&Event.xcookie;
-            if (cookie->extension == x11->present_code && x11->have_present &&
-                x11->has_mesa && !x11->has_nvidia)
+            if (cookie->extension == x11->present_code && x11->have_present)
             {
+                int present = x11->opts->x11_present;
+                bool use_present = (x11->has_mesa && !x11->has_nvidia &&
+                                   present) || present == 2;
                 XGetEventData(x11->display, cookie);
-                if (cookie->evtype == PresentCompleteNotify) {
+                if (cookie->evtype == PresentCompleteNotify && use_present) {
                     XPresentCompleteNotifyEvent *present_event;
                     present_event = (XPresentCompleteNotifyEvent *)cookie->data;
                     present_update_sync_values(x11->present, present_event->ust,