-/* one border for Zborder elements, one border for steelwall, if needed */
-#define CAVE_WIDTH (MAX_PLAYFIELD_WIDTH + 2 + 2)
-#define CAVE_HEIGHT (MAX_PLAYFIELD_HEIGHT + 2 + 2)
+/* with border for steelwall, if needed (when converted from R'n'D level) */
+#define CAVE_WIDTH (MAX_PLAYFIELD_WIDTH + 2)
+#define CAVE_HEIGHT (MAX_PLAYFIELD_HEIGHT + 2)
+
+/* with border for Zborder elements (surrounding the visible playfield) */
+#define CAVE_BUFFER_XOFFSET 1
+#define CAVE_BUFFER_YOFFSET 1
+#define CAVE_BUFFER_WIDTH (CAVE_WIDTH + 2 * CAVE_BUFFER_XOFFSET)
+#define CAVE_BUFFER_HEIGHT (CAVE_HEIGHT + 2 * CAVE_BUFFER_YOFFSET)