Add initial prototype.

3-mid/opengl/source/lean/support/opengl-frame_counter.ads

@@ -0,0 +1,24 @@
+private
+with
+     ada.Calendar;
+
+package openGL.frame_Counter
+--
+-- A utility which reports frames per second.
+--
+is
+   type Item is tagged private;
+
+   procedure increment (Self : in out Item);
+
+
+
+private
+
+   type Item is tagged
+      record
+         frame_Count   : Natural           := 0;
+         next_FPS_Time : ada.Calendar.Time := ada.Calendar.Clock;
+      end record;
+
+end openGL.frame_Counter;