From 9c2f46b0d5a5dce636522904fe0afbde78016063 Mon Sep 17 00:00:00 2001
From: David Gow <[EMAIL REDACTED]>
Date: Tue, 12 Apr 2022 15:23:22 +0800
Subject: [PATCH] Wayland: Add SDL_HINT_VIDEO_WAYLAND_PREFER_LIBDECOR
This hint allows libdecor to be used even when xdg-decoration is
available. It's mostly useful for debugging libdecor, but could in
theory be used by applications which want to (for example) bundle their
own libdecor plugins.
---
include/SDL_hints.h | 14 ++++++++++++++
src/video/wayland/SDL_waylandvideo.c | 25 ++++++++++++++++++++++++-
2 files changed, 38 insertions(+), 1 deletion(-)
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index 12466e99029..c5371324ada 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -1475,6 +1475,20 @@ extern "C" {
*/
#define SDL_HINT_VIDEO_WAYLAND_ALLOW_LIBDECOR "SDL_VIDEO_WAYLAND_ALLOW_LIBDECOR"
+/**
+ * \brief A variable controlling whether the libdecor Wayland backend is preferred over native decrations.
+ *
+ * When this hint is set, libdecor will be used to provide window decorations, even if xdg-decoration is
+ * available. (Note that, by default, libdecor will use xdg-decoration itself if available).
+ *
+ * This variable can be set to the following values:
+ * "0" - libdecor is enabled only if server-side decorations are unavailable.
+ * "1" - libdecor is always enabled if available.
+ *
+ * libdecor is used over xdg-shell when xdg-decoration protocol is unavailable.
+ */
+#define SDL_HINT_VIDEO_WAYLAND_PREFER_LIBDECOR "SDL_VIDEO_WAYLAND_PREFER_LIBDECOR"
+
/**
* \brief A variable that is the address of another SDL_Window* (as a hex string formatted with "%p").
*
diff --git a/src/video/wayland/SDL_waylandvideo.c b/src/video/wayland/SDL_waylandvideo.c
index 9c325d78a41..bce982fc682 100644
--- a/src/video/wayland/SDL_waylandvideo.c
+++ b/src/video/wayland/SDL_waylandvideo.c
@@ -876,6 +876,29 @@ static const struct wl_registry_listener registry_listener = {
display_handle_global,
display_remove_global
};
+
+#ifdef HAVE_LIBDECOR_H
+static SDL_bool should_use_libdecor(SDL_VideoData *data)
+{
+ if (!SDL_WAYLAND_HAVE_WAYLAND_LIBDECOR) {
+ return SDL_FALSE;
+ }
+
+ if (!SDL_GetHintBoolean(SDL_HINT_VIDEO_WAYLAND_ALLOW_LIBDECOR, SDL_TRUE)) {
+ return SDL_FALSE;
+ }
+
+ if (SDL_GetHintBoolean(SDL_HINT_VIDEO_WAYLAND_PREFER_LIBDECOR, SDL_FALSE)) {
+ return SDL_TRUE;
+ }
+
+ if (data->decoration_manager) {
+ return SDL_FALSE;
+ }
+
+ return SDL_TRUE;
+}
+#endif
int
Wayland_VideoInit(_THIS)
@@ -899,7 +922,7 @@ Wayland_VideoInit(_THIS)
#ifdef HAVE_LIBDECOR_H
/* Don't have server-side decorations? Try client-side instead. */
- if (!data->decoration_manager && SDL_WAYLAND_HAVE_WAYLAND_LIBDECOR && SDL_GetHintBoolean(SDL_HINT_VIDEO_WAYLAND_ALLOW_LIBDECOR, SDL_TRUE)) {
+ if (should_use_libdecor(data)) {
data->shell.libdecor = libdecor_new(data->display, &libdecor_interface);
/* If libdecor works, we don't need xdg-shell anymore. */