support XEmbed, and therefore Chromium on Linux

direct/src/plugin/p3d_plugin_config.h.pp

@@ -32,4 +32,7 @@
    be found.  Empty string for the default. */
 #$[]define P3D_PLUGIN_P3D_PLUGIN "$[subst \,\\,$[osfilename $[P3D_PLUGIN_P3D_PLUGIN]]]"
 
+/* We need to know whether GTK is enabled for XEmbed. */
+$[cdefine HAVE_GTK]
+
 #end p3d_plugin_config.h

direct/src/plugin_npapi/Sources.pp

@@ -7,7 +7,7 @@
 #define BUILD_DIRECTORY $[and $[HAVE_P3D_PLUGIN],$[HAVE_NPAPI]]
 
 #define _MT $[if $[P3D_PLUGIN_MT],_mt]
-#define USE_PACKAGES npapi
+#define USE_PACKAGES npapi gtk
 
 #begin lib_target
   // By Mozilla convention, on Windows at least, the generated DLL

direct/src/plugin_npapi/ppInstance.cxx

@@ -38,6 +38,12 @@
 #include <sys/time.h>
 #endif  // _WIN32
 
+#if defined(HAVE_GTK) && defined(HAVE_X11)
+#include <gtk/gtk.h>
+#include <gdk/gdkx.h>
+#endif  // HAVE_GTK
+
+
 PPInstance::FileDatas PPInstance::_file_datas;
 
 ////////////////////////////////////////////////////////////////////
@@ -127,6 +133,7 @@ PPInstance(NPMIMEType pluginType, NPP instance, uint16_t mode,
     }
   }
 
+  _use_xembed = false;
   _got_window = false;
   _python_window_open = false;
 #ifdef _WIN32
@@ -946,6 +953,20 @@ get_panda_script_object() {
   return _script_object;
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: PPInstance::set_xembed
+//       Access: Public
+//  Description: Sets the use_xembed flag, telling the instance what
+//               kind of window object to expect from NPAPI.  If this
+//               is true, the window object is an XID following the
+//               XEmbed specification; if false, it is a normal window
+//               handle.
+////////////////////////////////////////////////////////////////////
+void PPInstance::
+set_xembed(bool use_xembed) {
+  _use_xembed = use_xembed;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: PPInstance::p3dobj_to_variant
 //       Access: Public
@@ -1811,12 +1832,14 @@ send_window() {
     // (0, 0), since the window we were given is already placed in the
     // right spot.
 #ifdef _WIN32
+    assert(!_use_xembed);
     parent_window._window_handle_type = P3D_WHT_win_hwnd;
     parent_window._handle._win_hwnd._hwnd = (HWND)(_window.window);
     x = 0;
     y = 0;
 
 #elif defined(__APPLE__)
+    assert(!_use_xembed);
     parent_window._window_handle_type = _window_handle_type;
     if (_window_handle_type == P3D_WHT_osx_port) {
       NP_Port *port = (NP_Port *)_window.window;
@@ -1830,10 +1853,30 @@ send_window() {
     }
 
 #elif defined(HAVE_X11)
-    // We make it an 'unsigned long' instead of 'Window'
-    // to avoid nppanda3d.so getting a dependency on X11.
-    parent_window._window_handle_type = P3D_WHT_x11_window;
-    parent_window._handle._x11_window._xwindow = (unsigned long)(_window.window);
+    if (_use_xembed) {
+      // If we're using the XEmbed model, we've actually received an
+      // XID for a GtkSocket.
+#ifdef HAVE_GTK
+      // Create the appropriate GtkPlug.
+      GtkWidget *plug = gtk_plug_new((GdkNativeWindow)_window.window);
+      gtk_widget_show(plug);
+
+      // Now just get the X11 Window pointer to pass down to Panda,
+      // since that's what it will be expecting.  (Hmm, it would be
+      // nice to pass the XID object and use this system in general
+      // within Panda, but that's for the future, I think.)
+      nout << "original XID is " << _window.window << ", created X11 window " 
+           << GDK_DRAWABLE_XID(plug->window) << "\n";
+      parent_window._window_handle_type = P3D_WHT_x11_window;
+      parent_window._handle._x11_window._xwindow = (unsigned long)GDK_DRAWABLE_XID(plug->window);
+#endif  // HAVE_GTK
+    } else {
+      // If we're not using XEmbed, this is just a standard X11 Window
+      // pointer.  We make it an 'unsigned long' instead of 'Window'
+      // to avoid nppanda3d.so getting a dependency on X11.
+      parent_window._window_handle_type = P3D_WHT_x11_window;
+      parent_window._handle._x11_window._xwindow = (unsigned long)(_window.window);
+    }
     x = 0;
     y = 0;
 #endif

direct/src/plugin_npapi/ppInstance.h

@@ -63,6 +63,7 @@ public:
   bool handle_event(void *event);
 
   NPObject *get_panda_script_object();
+  void set_xembed(bool use_xembed);
 
   void p3dobj_to_variant(NPVariant *result, P3D_object *object);
   P3D_object *variant_to_p3dobj(const NPVariant *variant);
@@ -214,6 +215,7 @@ private:
   typedef vector<StreamingFileData *> FileDatas;
   static FileDatas _file_datas;
   
+  bool _use_xembed;
   bool _got_window;
   NPWindow _window;
 #ifdef _WIN32

direct/src/plugin_npapi/startup.cxx

@@ -562,19 +562,34 @@ NPP_GetValue(NPP instance, NPPVariable variable, void *value) {
       *(NPObject **)value = obj;
       return NPERR_NO_ERROR;
     }
+
   } else if (variable == NPPVpluginNeedsXEmbed) {
-    // We'll say yes if the browser supports it.
-    // This is necessary to support Chromium.
-    //NPBool supports_xembed = false;
-    //NPError err = browser->getvalue(instance, NPNVSupportsXEmbedBool, &supports_xembed);
-    //if (err != NPERR_NO_ERROR) {
-    //  supports_xembed = false;
-    //}
-    // At the moment, setting it to true doesn't work
-    // at all on Linux.  We'll have to fix that before
-    // we support Chromium, I suppose.
-    *((NPBool *)value) = false;
+    // If we have Gtk2 available, we can use it to support the XEmbed
+    // protocol, which Chromium (at least) requires.
+
+    // In this case, we'll say we can do it, if the browser supports
+    // it.  (Though probably the browser wouldn't be asking if it
+    // couldn't.)
+
+    NPBool supports_xembed = false;
+    NPError err = browser->getvalue(instance, NPNVSupportsXEmbedBool, &supports_xembed);
+    if (err != NPERR_NO_ERROR) {
+      supports_xembed = false;
+    }
+    nout << "browser supports_xembed: " << (bool)supports_xembed << "\n";
+#ifdef HAVE_GTK
+    bool plugin_supports = true;
+#else
+    bool plugin_supports = false;
+    supports_xembed = false;
+#endif  // HAVE_GTK
+    nout << "plugin supports_xembed: " << plugin_supports << "\n";
+
+    inst->set_xembed(supports_xembed);
+    *(NPBool *)value = supports_xembed;
+
     return NPERR_NO_ERROR;
+
   } else {
     return NP_GetValue(NULL, variable, value);
   }