Add initial prototype.

3-mid/opengl/source/lean/model/opengl-model-text.ads

@@ -0,0 +1,29 @@
+with
+     openGL.Font;
+
+
+package openGL.Model.text
+--
+--  Provides an abstract model for rendering text.
+--
+is
+   type Item is abstract new Model.item with private;
+   type View is access all Item'Class;
+
+
+   procedure Text_is (Self : in out Item;   Now : in String)   is abstract;
+   function  Text    (Self : in     Item)     return String    is abstract;
+
+   function  Font    (Self : in     Item)     return Font.view is abstract;
+
+   no_such_Font : exception;
+
+
+
+private
+
+   type Item is abstract new Model.item with null record;
+
+   type String_view is access String;
+
+end openGL.Model.text;