Merge pull request #1272 from emersion/presentation-time

Implement presentation-time

1 files changed, 17 insertions, 0 deletions

diff --git a/backend/multi/backend.c b/backend/multi/backend.c
index 2f4b929f..cefaa361 100644
--- a/backend/multi/backend.c
+++ b/backend/multi/backend.c
@@ -1,6 +1,8 @@
+#define _POSIX_C_SOURCE 199309L
 #include <assert.h>
 #include <stdbool.h>
 #include <stdlib.h>
+#include <time.h>
 #include <wlr/backend/interface.h>
 #include <wlr/backend/session.h>
 #include <wlr/util/log.h>
@@ -77,11 +79,26 @@ static struct wlr_session *multi_backend_get_session(
 	return backend->session;
 }
 
+static clockid_t multi_backend_get_presentation_clock(
+		struct wlr_backend *backend) {
+	struct wlr_multi_backend *multi = multi_backend_from_backend(backend);
+
+	struct subbackend_state *sub;
+	wl_list_for_each(sub, &multi->backends, link) {
+		if (sub->backend->impl->get_presentation_clock) {
+			return wlr_backend_get_presentation_clock(sub->backend);
+		}
+	}
+
+	return CLOCK_MONOTONIC;
+}
+
 struct wlr_backend_impl backend_impl = {
 	.start = multi_backend_start,
 	.destroy = multi_backend_destroy,
 	.get_renderer = multi_backend_get_renderer,
 	.get_session = multi_backend_get_session,
+	.get_presentation_clock = multi_backend_get_presentation_clock,
 };
 
 static void handle_display_destroy(struct wl_listener *listener, void *data) {