Bug 1460605 - Provide NS_NATIVE_EGL_WINDOW to get a native EGL window on Wayland, r=jhorak

Original patch author is Takuro Ashie <ashie@clear-code.com>

Provide ability to create native EGL window and provide it under NS_NATIVE_EGL_WINDOW
to GL code. The native EGL window is owned/managed by mozcontainer.

MozReview-Commit-ID: 4d0Kk6DRSaD

--HG--
extra : rebase_source : e4677ce51fbf918eb1b0257c66ca4b7220174bbb

config/system-headers.mozbuild

@@ -1339,3 +1339,9 @@ if CONFIG['MOZ_SYSTEM_ICU']:
         'unicode/ustring.h',
         'unicode/utypes.h',
     ]
+
+if CONFIG['MOZ_WAYLAND']:
+    system_headers += [
+        'wayland-client.h',
+        'wayland-egl.h',
+    ]

widget/gtk/mozcontainer.cpp

@@ -10,6 +10,7 @@
 #ifdef MOZ_WAYLAND
 #include <gdk/gdkx.h>
 #include <gdk/gdkwayland.h>
+#include <wayland-egl.h>
 #endif
 #include <stdio.h>
 #include <dlfcn.h>
@@ -207,6 +208,11 @@ moz_container_init (MozContainer *container)
 
 #if defined(MOZ_WAYLAND)
     {
+      container->subcompositor = nullptr;
+      container->surface = nullptr;
+      container->subsurface = nullptr;
+      container->eglwindow = nullptr;
+
       GdkDisplay *gdk_display = gtk_widget_get_display(GTK_WIDGET(container));
       if (GDK_IS_WAYLAND_DISPLAY (gdk_display)) {
           // Available as of GTK 3.8+
@@ -289,6 +295,7 @@ moz_container_map_surface(MozContainer *container)
 static void
 moz_container_unmap_surface(MozContainer *container)
 {
+    g_clear_pointer(&container->eglwindow, wl_egl_window_destroy);
     g_clear_pointer(&container->subsurface, wl_subsurface_destroy);
     g_clear_pointer(&container->surface, wl_surface_destroy);
 }
@@ -434,6 +441,11 @@ moz_container_size_allocate (GtkWidget     *widget,
         gdk_window_get_position(gtk_widget_get_window(widget), &x, &y);
         wl_subsurface_set_position(container->subsurface, x, y);
     }
+    if (container->eglwindow) {
+        wl_egl_window_resize(container->eglwindow,
+                             allocation->width, allocation->height,
+                             0, 0);
+    }
 #endif
 }
 
@@ -559,4 +571,27 @@ moz_container_get_wl_surface(MozContainer *container)
 
     return container->surface;
 }
+
+struct wl_egl_window *
+moz_container_get_wl_egl_window(MozContainer *container)
+{
+    if (!container->eglwindow) {
+        struct wl_surface *wlsurf = moz_container_get_wl_surface(container);
+        if (!wlsurf)
+            return nullptr;
+
+      GdkWindow *window = gtk_widget_get_window(GTK_WIDGET(container));
+      container->eglwindow
+            = wl_egl_window_create(wlsurf,
+                                   gdk_window_get_width(window),
+                                   gdk_window_get_height(window));
+    }
+    return container->eglwindow;
+}
+
+gboolean
+moz_container_has_wl_egl_window(MozContainer *container)
+{
+    return container->eglwindow ? true : false;
+}
 #endif

widget/gtk/mozcontainer.h

@@ -72,6 +72,7 @@ struct _MozContainer
     struct wl_subcompositor *subcompositor;
     struct wl_surface       *surface;
     struct wl_subsurface    *subsurface;
+    struct wl_egl_window    *eglwindow;
 #endif
 };
 
@@ -95,6 +96,8 @@ void       moz_container_move          (MozContainer *container,
 
 #ifdef MOZ_WAYLAND
 struct wl_surface* moz_container_get_wl_surface(MozContainer *container);
+struct wl_egl_window* moz_container_get_wl_egl_window(MozContainer *container);
+gboolean moz_container_has_wl_egl_window(MozContainer *container);
 #endif
 
 #endif /* __MOZ_CONTAINER_H__ */

widget/gtk/mozwayland/mozwayland.c

@@ -271,3 +271,21 @@ wl_log_set_handler_client(wl_log_func_t handler)
 {
 }
 
+MOZ_EXPORT struct wl_egl_window *
+wl_egl_window_create(struct wl_surface *surface,
+                     int width, int height)
+{
+    return NULL;
+}
+
+MOZ_EXPORT void
+wl_egl_window_destroy(struct wl_egl_window *egl_window)
+{
+}
+
+MOZ_EXPORT void
+wl_egl_window_resize(struct wl_egl_window *egl_window,
+                     int width, int height,
+                     int dx, int dy)
+{
+}

widget/gtk/nsWindow.cpp

@@ -1739,6 +1739,15 @@ nsWindow::GetNativeData(uint32_t aDataType)
     case NS_NATIVE_COMPOSITOR_DISPLAY:
         return gfxPlatformGtk::GetPlatform()->GetCompositorDisplay();
 #endif // MOZ_X11
+    case NS_NATIVE_EGL_WINDOW: {
+        if (mIsX11Display)
+            return mGdkWindow ? (void*)GDK_WINDOW_XID(mGdkWindow) : nullptr;
+#ifdef MOZ_WAYLAND
+        if (mContainer)
+            return moz_container_get_wl_egl_window(mContainer);
+#endif
+        return nullptr;
+    }
     default:
         NS_WARNING("nsWindow::GetNativeData called with bad value");
         return nullptr;
@@ -4308,6 +4317,16 @@ nsWindow::NativeShow(bool aAction)
         }
     }
     else {
+#ifdef MOZ_WAYLAND
+        if (mContainer && moz_container_has_wl_egl_window(mContainer)) {
+            // Because wl_egl_window is destroyed on moz_container_unmap(),
+            // the current compositor cannot use it anymore. To avoid crash,
+            // destroy the compositor & recreate a new compositor on next
+            // expose event.
+            DestroyLayerManager();
+        }
+#endif
+
         if (mIsTopLevel) {
             // Workaround window freezes on GTK versions before 3.21.2 by
             // ensuring that configure events get dispatched to windows before

widget/nsIWidget.h

@@ -143,6 +143,7 @@ typedef void* nsNativeWidget;
 #ifdef MOZ_X11
 #define NS_NATIVE_COMPOSITOR_DISPLAY   105
 #endif // MOZ_X11
+#define NS_NATIVE_EGL_WINDOW           106
 #endif
 #ifdef MOZ_WIDGET_ANDROID
 #define NS_JAVA_SURFACE                100