-GMainLoop *mainloop; /* event loop */
-GtkWidget *toplevel; /* top level window */
-GtkWidget *report_label; /* label for progress indicator */
-GtkWidget *tabs; /* main tabs */
+/** @brief Event loop */
+GMainLoop *mainloop;
+
+/** @brief Top-level window */
+GtkWidget *toplevel;
+
+/** @brief Label for progress indicator */
+GtkWidget *report_label;
+
+/** @brief Main tab group */
+GtkWidget *tabs;
+
+/** @brief Main client */
+disorder_eclient *client;
+
+/** @brief Last reported state
+ *
+ * This is updated by log_state().
+ */
+unsigned long last_state;
+
+/** @brief True if some track is playing
+ *
+ * This ought to be removed in favour of last_state & DISORDER_PLAYING
+ */
+int playing;
+
+/** @brief Left channel volume */
+int volume_l;