+/* values for vertical screen retrace synchronization (vsync) */
+#define STR_VSYNC_MODE_OFF "off"
+#define STR_VSYNC_MODE_NORMAL "normal"
+#define STR_VSYNC_MODE_ADAPTIVE "adaptive"
+
+#define STR_VSYNC_MODE_DEFAULT STR_VSYNC_MODE_OFF
+
+#define VSYNC_MODE_OFF 0
+#define VSYNC_MODE_NORMAL 1
+#define VSYNC_MODE_ADAPTIVE -1
+
+#define VSYNC_MODE_DEFAULT VSYNC_MODE_OFF
+