Add initial prototype.

3-mid/opengl/applet/demo/models/model_scaling/launch_model_scaling.adb

@@ -0,0 +1,87 @@
+with
+     openGL.Visual,
+     openGL.Demo,
+     openGL.Model.terrain;
+
+
+procedure launch_Model_scaling
+--
+--  Exercise the scaling of models.
+--
+is
+   use openGL,
+       openGL.Math,
+       openGL.linear_Algebra_3d;
+begin
+   Demo.print_Usage;
+   Demo.define ("openGL 'Model Scaling' Demo");
+   Demo.Camera.Position_is ([0.0, 0.0, 20.0],
+                            y_Rotation_from (to_Radians (0.0)));
+   declare
+      --  The models.
+      --
+      the_Models : constant openGL.Model.views := openGL.Demo.Models;
+
+      --  The visuals.
+      --
+      the_Visuals : openGL.Visual.views (the_Models'Range);
+      ground_Id   : Positive;
+
+      --  Scaling
+      --
+      scaling_Up  : Boolean       := True;
+      Scale       : math.Vector_3 := [1.0, 1.0, 1.0];
+
+   begin
+      for i in the_Visuals'Range
+      loop
+         the_Visuals (i) := Visual.Forge.new_Visual (the_Models (i));
+
+         if the_Models (i).all in openGL.Model.terrain.item'Class
+         then
+            ground_Id := i;
+         end if;
+      end loop;
+
+      Demo.layout (the_Visuals);
+      the_Visuals (ground_Id).Site_is (the_Visuals (ground_Id).Site_of + [0.0, -15.0, 0.0]);
+
+
+      --  Main loop.
+      --
+      while not Demo.Done
+      loop
+         if scaling_Up then Scale := Scale + [0.001, 0.001, 0.001];
+                       else Scale := Scale - [0.001, 0.001, 0.001];
+         end if;
+
+         if    Scale (1) > 2.0   then scaling_Up := False;
+         elsif Scale (1) < 0.002 then scaling_Up := True;
+         end if;
+
+         for Each of the_Visuals
+         loop
+            Each.Scale_is (Scale);
+         end loop;
+
+         -- Handle user commands.
+         --
+         Demo.Dolly.evolve;
+         Demo.Done := Demo.Dolly.quit_Requested;
+
+         --  Render the sprites.
+         --
+         Demo.Camera.render (the_Visuals);
+
+         while not Demo.Camera.cull_Completed
+         loop
+            delay Duration'Small;
+         end loop;
+
+         Demo.Renderer.render;
+         Demo.FPS_Counter.increment;    -- Frames per second display.
+      end loop;
+   end;
+
+   Demo.destroy;
+end launch_Model_scaling;

3-mid/opengl/applet/demo/models/model_scaling/model_scaling.gpr

@@ -0,0 +1,20 @@
+with
+     "opengl_demo",
+     "lace_shared"; 
+
+project Model_scaling
+is
+   for Object_Dir use "build";
+   for Exec_Dir use ".";
+   for Main use ("launch_model_scaling.adb");
+
+   package Ide      renames Lace_shared.Ide;
+   package Builder  renames Lace_shared.Builder;
+   package Compiler renames Lace_shared.Compiler;
+   package Binder   renames Lace_shared.Binder;
+
+   package Linker is
+      for Default_Switches ("ada") use ("-g", "-lX11", "-lGL", "-lexpat");
+   end Linker;
+
+end Model_scaling;