} vtbl;
+ /**
+ * Set if rendering has occured to the drawable's front buffer.
+ *
+ * This is used in the DRI2 case to detect that glFlush should also copy
+ * the contents of the fake front buffer to the real front buffer.
+ */
+ bool front_buffer_dirty;
+
+ /**
+ * Track whether front-buffer rendering is currently enabled
+ *
+ * A separate flag is used to track this in order to support MRT more
+ * easily.
+ */
+ bool is_front_buffer_rendering;
+
+ /**
+ * Track whether front-buffer is the current read target.
+ *
+ * This is closely associated with is_front_buffer_rendering, but may
+ * be set separately. The DRI2 fake front buffer must be referenced
+ * either way.
+ */
+ bool is_front_buffer_reading;
+
/** drirc option cache */
driOptionCache optionCache;