wayland: ask KDE protocol extension to use server-side decorations if possible.

src/video/wayland/SDL_waylandvideo.c

@@ -47,6 +47,7 @@
 
 #include "xdg-shell-client-protocol.h"
 #include "xdg-shell-unstable-v6-client-protocol.h"
+#include "org-kde-kwin-server-decoration-manager-client-protocol.h"
 
 #define WAYLANDVID_DRIVER_NAME "wayland"
 
@@ -182,6 +183,7 @@ Wayland_CreateDevice(int devindex)
     device->SetWindowFullscreen = Wayland_SetWindowFullscreen;
     device->MaximizeWindow = Wayland_MaximizeWindow;
     device->RestoreWindow = Wayland_RestoreWindow;
+    device->SetWindowBordered = Wayland_SetWindowBordered;
     device->SetWindowSize = Wayland_SetWindowSize;
     device->SetWindowTitle = Wayland_SetWindowTitle;
     device->DestroyWindow = Wayland_DestroyWindow;
@@ -345,6 +347,8 @@ display_handle_global(void *data, struct wl_registry *registry, uint32_t id,
 {
     SDL_VideoData *d = data;
 
+    /*printf("WAYLAND INTERFACE: %s\n", interface);*/
+
     if (strcmp(interface, "wl_compositor") == 0) {
         d->compositor = wl_registry_bind(d->registry, id, &wl_compositor_interface, 1);
     } else if (strcmp(interface, "wl_output") == 0) {
@@ -368,6 +372,8 @@ display_handle_global(void *data, struct wl_registry *registry, uint32_t id,
         Wayland_display_add_pointer_constraints(d, id);
     } else if (strcmp(interface, "wl_data_device_manager") == 0) {
         d->data_device_manager = wl_registry_bind(d->registry, id, &wl_data_device_manager_interface, 3);
+    } else if (strcmp(interface, "org_kde_kwin_server_decoration_manager") == 0) {
+        d->kwin_server_decoration_manager = wl_registry_bind(d->registry, id, &org_kde_kwin_server_decoration_manager_interface, 1);
 
 #ifdef SDL_VIDEO_DRIVER_WAYLAND_QT_TOUCH
     } else if (strcmp(interface, "qt_touch_extension") == 0) {

src/video/wayland/SDL_waylandvideo.h

@@ -61,6 +61,7 @@ typedef struct {
     struct zwp_relative_pointer_manager_v1 *relative_pointer_manager;
     struct zwp_pointer_constraints_v1 *pointer_constraints;
     struct wl_data_device_manager *data_device_manager;
+    struct org_kde_kwin_server_decoration_manager *kwin_server_decoration_manager;
 
     EGLDisplay edpy;
     EGLContext context;

src/video/wayland/SDL_waylandwindow.c

@@ -35,6 +35,7 @@
 
 #include "xdg-shell-client-protocol.h"
 #include "xdg-shell-unstable-v6-client-protocol.h"
+#include "org-kde-kwin-server-decoration-manager-client-protocol.h"
 
 /* On modern desktops, we probably will use the xdg-shell protocol instead
    of wl_shell, but wl_shell might be useful on older Wayland installs that
@@ -459,6 +460,17 @@ Wayland_RestoreWindow(_THIS, SDL_Window * window)
     WAYLAND_wl_display_flush( ((SDL_VideoData*)_this->driverdata)->display );
 }
 
+void
+Wayland_SetWindowBordered(_THIS, SDL_Window * window, SDL_bool bordered)
+{
+    SDL_WindowData *wind = window->driverdata;
+    const SDL_VideoData *viddata = (const SDL_VideoData *) _this->driverdata;
+    if ((viddata->kwin_server_decoration_manager) && (wind->kwin_server_decoration)) {
+        const enum org_kde_kwin_server_decoration_mode mode = bordered ? ORG_KDE_KWIN_SERVER_DECORATION_MANAGER_MODE_SERVER : ORG_KDE_KWIN_SERVER_DECORATION_MANAGER_MODE_NONE;
+        org_kde_kwin_server_decoration_request_mode(wind->kwin_server_decoration, mode);
+    }
+}
+
 void
 Wayland_MaximizeWindow(_THIS, SDL_Window * window)
 {
@@ -570,6 +582,15 @@ int Wayland_CreateWindow(_THIS, SDL_Window *window)
     }
 #endif /* SDL_VIDEO_DRIVER_WAYLAND_QT_TOUCH */
 
+    if (c->kwin_server_decoration_manager) {
+        data->kwin_server_decoration = org_kde_kwin_server_decoration_manager_create(c->kwin_server_decoration_manager, data->surface);
+        if (data->kwin_server_decoration) {
+            const SDL_bool bordered = (window->flags & SDL_WINDOW_BORDERLESS) == 0;
+            const enum org_kde_kwin_server_decoration_mode mode = bordered ? ORG_KDE_KWIN_SERVER_DECORATION_MANAGER_MODE_SERVER : ORG_KDE_KWIN_SERVER_DECORATION_MANAGER_MODE_NONE;
+            org_kde_kwin_server_decoration_request_mode(data->kwin_server_decoration, mode);
+        }
+    }
+
     region = wl_compositor_create_region(c->compositor);
     wl_region_add(region, 0, 0, window->w, window->h);
     wl_surface_set_opaque_region(data->surface, region);
@@ -644,6 +665,10 @@ void Wayland_DestroyWindow(_THIS, SDL_Window *window)
         SDL_EGL_DestroySurface(_this, wind->egl_surface);
         WAYLAND_wl_egl_window_destroy(wind->egl_window);
 
+        if (wind->kwin_server_decoration) {
+            org_kde_kwin_server_decoration_release(wind->kwin_server_decoration);
+        }
+
         if (data->shell.xdg) {
             if (wind->shell_surface.xdg.roleobj.toplevel) {
                 xdg_toplevel_destroy(wind->shell_surface.xdg.roleobj.toplevel);

src/video/wayland/SDL_waylandwindow.h

@@ -62,6 +62,7 @@ typedef struct {
     struct SDL_WaylandInput *keyboard_device;
     EGLSurface egl_surface;
     struct zwp_locked_pointer_v1 *locked_pointer;
+    struct org_kde_kwin_server_decoration *kwin_server_decoration;
 
 #ifdef SDL_VIDEO_DRIVER_WAYLAND_QT_TOUCH
     struct qt_extended_surface *extended_surface;
@@ -74,6 +75,7 @@ extern void Wayland_SetWindowFullscreen(_THIS, SDL_Window * window,
                                         SDL_bool fullscreen);
 extern void Wayland_MaximizeWindow(_THIS, SDL_Window * window);
 extern void Wayland_RestoreWindow(_THIS, SDL_Window * window);
+extern void Wayland_SetWindowBordered(_THIS, SDL_Window * window, SDL_bool bordered);
 extern int Wayland_CreateWindow(_THIS, SDL_Window *window);
 extern void Wayland_SetWindowSize(_THIS, SDL_Window * window);
 extern void Wayland_SetWindowTitle(_THIS, SDL_Window * window);

wayland-protocols/org-kde-kwin-server-decoration-manager.xml

@@ -0,0 +1,94 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="server_decoration">
+  <copyright><![CDATA[
+    Copyright (C) 2015 Martin Gräßlin
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 2.1 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+  ]]></copyright>
+  <interface  name="org_kde_kwin_server_decoration_manager" version="1">
+      <description summary="Server side window decoration manager">
+        This interface allows to coordinate whether the server should create
+        a server-side window decoration around a wl_surface representing a
+        shell surface (wl_shell_surface or similar). By announcing support
+        for this interface the server indicates that it supports server
+        side decorations.
+      </description>
+      <request name="create">
+        <description summary="Create a server-side decoration object for a given surface">
+            When a client creates a server-side decoration object it indicates
+            that it supports the protocol. The client is supposed to tell the
+            server whether it wants server-side decorations or will provide
+            client-side decorations.
+
+            If the client does not create a server-side decoration object for
+            a surface the server interprets this as lack of support for this
+            protocol and considers it as client-side decorated. Nevertheless a
+            client-side decorated surface should use this protocol to indicate
+            to the server that it does not want a server-side deco.
+        </description>
+        <arg name="id" type="new_id" interface="org_kde_kwin_server_decoration"/>
+        <arg name="surface" type="object" interface="wl_surface"/>
+      </request>
+      <enum name="mode">
+            <description summary="Possible values to use in request_mode and the event mode."/>
+            <entry name="None" value="0" summary="Undecorated: The surface is not decorated at all, neither server nor client-side. An example is a popup surface which should not be decorated."/>
+            <entry name="Client" value="1" summary="Client-side decoration: The decoration is part of the surface and the client."/>
+            <entry name="Server" value="2" summary="Server-side decoration: The server embeds the surface into a decoration frame."/>
+      </enum>
+      <event name="default_mode">
+          <description summary="The default mode used on the server">
+              This event is emitted directly after binding the interface. It contains
+              the default mode for the decoration. When a new server decoration object
+              is created this new object will be in the default mode until the first
+              request_mode is requested.
+
+              The server may change the default mode at any time.
+          </description>
+          <arg name="mode" type="uint" summary="The default decoration mode applied to newly created server decorations."/>
+      </event>
+  </interface>
+  <interface name="org_kde_kwin_server_decoration" version="1">
+      <request name="release" type="destructor">
+        <description summary="release the server decoration object"/>
+      </request>
+      <enum name="mode">
+            <description summary="Possible values to use in request_mode and the event mode."/>
+            <entry name="None" value="0" summary="Undecorated: The surface is not decorated at all, neither server nor client-side. An example is a popup surface which should not be decorated."/>
+            <entry name="Client" value="1" summary="Client-side decoration: The decoration is part of the surface and the client."/>
+            <entry name="Server" value="2" summary="Server-side decoration: The server embeds the surface into a decoration frame."/>
+      </enum>
+      <request name="request_mode">
+          <description summary="The decoration mode the surface wants to use."/>
+          <arg name="mode" type="uint" summary="The mode this surface wants to use."/>
+      </request>
+      <event name="mode">
+          <description summary="The new decoration mode applied by the server">
+              This event is emitted directly after the decoration is created and
+              represents the base decoration policy by the server. E.g. a server
+              which wants all surfaces to be client-side decorated will send Client,
+              a server which wants server-side decoration will send Server.
+
+              The client can request a different mode through the decoration request.
+              The server will acknowledge this by another event with the same mode. So
+              even if a server prefers server-side decoration it's possible to force a
+              client-side decoration.
+
+              The server may emit this event at any time. In this case the client can
+              again request a different mode. It's the responsibility of the server to
+              prevent a feedback loop.
+          </description>
+          <arg name="mode" type="uint" summary="The decoration mode applied to the surface by the server."/>
+      </event>
+  </interface>
+</protocol>