+ /**
+ * For interface blocks, members may have an explicit byte offset
+ * specified; -1 otherwise. Also used for xfb_offset layout qualifier.
+ *
+ * Unless used for xfb_offset this field is ignored for structs.
+ */
+ int offset;
+
+ /**
+ * For interface blocks, members may define a transform feedback buffer;
+ * -1 otherwise.
+ */
+ int xfb_buffer;
+
+ /**
+ * For interface blocks, members may define a transform feedback stride;
+ * -1 otherwise.
+ */
+ int xfb_stride;
+