Add initial prototype.

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

@@ -0,0 +1,31 @@
+with
+     openGL.Camera,
+     ada.Characters.latin_1;
+
+package openGL.Dolly
+--
+-- A utility which moves a camera via the keyboard.
+--
+is
+   type Item (Camera : openGL.Camera.view) is tagged private;
+
+
+   procedure Speed_is           (Self : in out Item;   Now : in Real);
+   procedure evolve             (Self : in out Item);
+
+   function  quit_Requested     (Self : in     Item) return Boolean;
+
+   procedure get_last_Character (Self : in out Item;   the_Character : out Character;
+                                                       Available     : out Boolean);
+
+
+private
+
+   type Item (Camera : openGL.Camera.view) is tagged
+      record
+         quit_Requested : Boolean   := False;
+         last_Character : Character := ada.Characters.Latin_1.NUL;
+         Speed          : Real      := 1.0;
+      end record;
+
+end openGL.Dolly;