Wayland: report when video drivers can't be loaded or found

This brings it to parity with the X11 backend.

platform/linuxbsd/wayland/display_server_wayland.cpp

@@ -1259,23 +1259,39 @@ DisplayServerWayland::DisplayServerWayland(const String &p_rendering_driver, Win
 
  rendering_driver = p_rendering_driver;
 
+ bool driver_found = false;
+ String executable_name = OS::get_singleton()->get_executable_path().get_file();
+
 #ifdef RD_ENABLED
 #ifdef VULKAN_ENABLED
  if (rendering_driver == "vulkan") {
  rendering_context = memnew(RenderingContextDriverVulkanWayland);
  }
-#endif
+#endif // VULKAN_ENABLED
 
  if (rendering_context) {
  if (rendering_context->initialize() != OK) {
- ERR_PRINT(vformat("Could not initialize %s", rendering_driver));
  memdelete(rendering_context);
  rendering_context = nullptr;
  r_error = ERR_CANT_CREATE;
- return;
+
+ if (p_rendering_driver == "vulkan") {
+ OS::get_singleton()->alert(
+ vformat("Your video card drivers seem not to support the required Vulkan version.\n\n"
+ "If possible, consider updating your video card drivers or using the OpenGL 3 driver.\n\n"
+ "You can enable the OpenGL 3 driver by starting the engine from the\n"
+ "command line with the command:\n\n \"%s\" --rendering-driver opengl3\n\n"
+ "If you recently updated your video card drivers, try rebooting.",
+ executable_name),
+ "Unable to initialize Vulkan video driver");
+ }
+
+ ERR_FAIL_MSG(vformat("Could not initialize %s", rendering_driver));
  }
+
+ driver_found = true;
  }
-#endif
+#endif // RD_ENABLED
 
 #ifdef GLES3_ENABLED
  if (rendering_driver == "opengl3" || rendering_driver == "opengl3_es") {
@@ -1341,26 +1357,53 @@ DisplayServerWayland::DisplayServerWayland(const String &p_rendering_driver, Win
  rendering_driver = "opengl3_es";
  } else {
  r_error = ERR_UNAVAILABLE;
+
+ OS::get_singleton()->alert(
+ vformat("Your video card drivers seem not to support the required OpenGL 3.3 version.\n\n"
+ "If possible, consider updating your video card drivers or using the Vulkan driver.\n\n"
+ "You can enable the Vulkan driver by starting the engine from the\n"
+ "command line with the command:\n\n \"%s\" --rendering-driver vulkan\n\n"
+ "If you recently updated your video card drivers, try rebooting.",
+ executable_name),
+ "Unable to initialize OpenGL video driver");
+
  ERR_FAIL_MSG("Could not initialize OpenGL.");
  }
  } else {
  RasterizerGLES3::make_current(true);
+ driver_found = true;
  }
  }
 
  if (rendering_driver == "opengl3_es") {
  egl_manager = memnew(EGLManagerWaylandGLES);
 
- if (egl_manager->initialize() != OK) {
+ if (egl_manager->initialize() != OK || egl_manager->open_display(wayland_thread.get_wl_display()) != OK) {
  memdelete(egl_manager);
  egl_manager = nullptr;
  r_error = ERR_CANT_CREATE;
- ERR_FAIL_MSG("Could not initialize GLES3.");
+
+ OS::get_singleton()->alert(
+ vformat("Your video card drivers seem not to support the required OpenGL ES 3.0 version.\n\n"
+ "If possible, consider updating your video card drivers or using the Vulkan driver.\n\n"
+ "You can enable the Vulkan driver by starting the engine from the\n"
+ "command line with the command:\n\n \"%s\" --rendering-driver vulkan\n\n"
+ "If you recently updated your video card drivers, try rebooting.",
+ executable_name),
+ "Unable to initialize OpenGL ES video driver");
+
+ ERR_FAIL_MSG("Could not initialize OpenGL ES.");
  }
 
  RasterizerGLES3::make_current(false);
+ driver_found = true;
  }
  }
+
+ if (!driver_found) {
+ r_error = ERR_UNAVAILABLE;
+ ERR_FAIL_MSG("Video driver not found.");
+ }
 #endif // GLES3_ENABLED
 
  cursor_set_shape(CURSOR_BUSY);
@@ -1384,12 +1427,12 @@ DisplayServerWayland::DisplayServerWayland(const String &p_rendering_driver, Win
 
  RendererCompositorRD::make_current();
  }
-#endif
+#endif // RD_ENABLED
 
 #ifdef DBUS_ENABLED
  portal_desktop = memnew(FreeDesktopPortalDesktop);
  screensaver = memnew(FreeDesktopScreenSaver);
-#endif
+#endif // DBUS_ENABLED
 
  screen_set_keep_on(GLOBAL_GET("display/window/energy_saving/keep_screen_on"));