73 lines
2.1 KiB
Ada
73 lines
2.1 KiB
Ada
with Ada.Numerics.Elementary_Functions;
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with SDL.Video.Windows.Makers;
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with SDL.Video.Renderers.Makers;
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with SDL.Events.Events;
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procedure Superelipse is
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Width : constant := 600;
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Height : constant := 600;
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A : constant := 200.0;
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B : constant := 200.0;
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N : constant := 2.5;
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Window : SDL.Video.Windows.Window;
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Renderer : SDL.Video.Renderers.Renderer;
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Event : SDL.Events.Events.Events;
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procedure Draw_Superelipse
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is
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use type SDL.C.int;
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use Ada.Numerics.Elementary_Functions;
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Xx, Yy : Float;
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subtype Legal_Range is Float range 0.980 .. 1.020;
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begin
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for Y in 0 .. Height loop
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for X in 0 .. Width loop
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Xx := Float (X - Width / 2);
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Yy := Float (Y - Height / 2);
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if (abs (Xx / A)) ** N + (abs (Yy / B)) ** N in Legal_Range then
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Renderer.Draw (Point => (X => Width / 2 + SDL.C.int (Xx),
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Y => Height / 2 - SDL.C.int (Yy)));
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end if;
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end loop;
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end loop;
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end Draw_Superelipse;
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procedure Wait is
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use type SDL.Events.Event_Types;
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begin
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loop
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while SDL.Events.Events.Poll (Event) loop
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if Event.Common.Event_Type = SDL.Events.Quit then
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return;
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end if;
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end loop;
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delay 0.100;
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end loop;
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end Wait;
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begin
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if not SDL.Initialise (Flags => SDL.Enable_Screen) then
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return;
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end if;
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SDL.Video.Windows.Makers.Create (Win => Window,
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Title => "Superelipse",
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Position => SDL.Natural_Coordinates'(X => 10, Y => 10),
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Size => SDL.Positive_Sizes'(Width, Height),
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Flags => 0);
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SDL.Video.Renderers.Makers.Create (Renderer, Window.Get_Surface);
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Renderer.Set_Draw_Colour ((0, 0, 0, 255));
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Renderer.Fill (Rectangle => (0, 0, Width, Height));
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Renderer.Set_Draw_Colour ((0, 220, 0, 255));
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Draw_Superelipse;
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Window.Update_Surface;
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Wait;
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Window.Finalize;
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SDL.Finalise;
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end Superelipse;
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