Add initial prototype.

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

@@ -0,0 +1,53 @@
+with
+     openGL.Geometry,
+     openGL.Palette;
+
+
+package openGL.Model.hex_grid
+--
+--  Models a regular hexagon grid.
+--
+is
+   type Item is new Model.item with private;
+   type View is access all Item'Class;
+
+
+   type height_Map_view is access all height_Map;
+
+
+   ---------
+   --- Forge
+   --
+
+   function new_Grid (heights_Asset : in asset_Name;
+                      Heights       : in height_Map_view;
+                      Color         : in lucid_Color := (palette.White,
+                                                         Opaque)) return View;
+   overriding
+   procedure destroy (Self : in out Item);
+
+
+   --------------
+   --- Attributes
+   --
+
+   overriding
+   function to_GL_Geometries (Self : access Item;   Textures : access Texture.name_Map_of_texture'Class;
+                                                    Fonts    : in     Font.font_id_Map_of_font) return Geometry.views;
+
+
+private
+
+   type Item is new Model.item with
+      record
+         heights_Asset : asset_Name     := null_Asset;
+         Heights       : height_Map_view;
+         Color         : rgba_Color;
+      end record;
+
+
+   overriding
+   procedure set_Bounds (Self : in out Item);
+
+
+end openGL.Model.hex_grid;