--
-- (C) 2000 Michal Zalewski <lcamtuf@tpi.pl>
--
-- Amazing, brand new Ada fuzz-zoom-rotator
--
-- Requires svgalib Ada binding. Available at:
-- http://www.gnuada.org/linux/
--
-- gnatmake fuzz -cargs -O3 -ffast-math

with Ada.Text_Io,Interfaces.C,Interfaces.C.Strings,Ada.Unchecked_Conversion;
with Ada.Calendar.Delays,Ada.Numerics.Aux,SVGALib.VGA;

use Ada.Numerics.Aux,SVGALib.VGA,SVGALib,Ada.Text_IO,Interfaces;

procedure fuzz is

  pragma Linker_Options ("-lvga");

  pragma Optimize (Time);

  subtype Wsp_X is Natural range 0 .. 319;
  subtype Wsp_Y is Natural range 0 .. 199;

  type Linia is array (Wsp_X) of Byte;
  type DuzaLinia is array ( -380 .. 380 ) of Byte;

  type Ekran_Obiekt is array (Wsp_Y) of Linia;
  type Ekran_Access is access all Ekran_Obiekt;

  Bufor		: Ekran_Obiekt;
  Ekran         : Ekran_Access;
  Tmp		: array ( - 380 .. 380 ) of DuzaLinia;

  Fuzz		: Integer;  
  Phase 	: Float := 0.0;
  Phase2  	: Float := 1.0;
  Phase3  	: Float := 1.0;
  Dodaj2	: Float := 0.08;
  Dodaj		: Float := 0.0001;
  XSin,XCos	: Float;
  X,Y		: Integer;
  MXCos,MXSin	: Integer;

  Hopa		: Integer := 4;

  function Byte_Access_To_Ekran_Access is new 
    Ada.Unchecked_Conversion(Source => Byte_Access,Target => Ekran_Access);

  procedure Set_Custom_Palette is
  begin
    for i in 0 .. 255 loop
      Set_Palette(i, Unsigned_8(0), Unsigned_8(0), Unsigned_8(Float(i)/4.05) );
    end loop;
  end Set_Custom_Palette;

begin

  for a in Tmp'Range loop

    for b in DuzaLinia'Range loop

      Tmp(a)(b) := Unsigned_8 ( Sin(Double(a)/10.0 ) * Sin(Double(b)/10.0 ) 
                                * 127.0 + 127.0 );

    end loop;

  end loop;

  Set_Mode(G320x200x256);

  Ekran := Byte_Access_To_Ekran_Access(Graph_Mem);

  Set_Custom_Palette;

  for a in 0 .. 1000000 loop

    Phase := Phase + Dodaj;

    if Phase > 0.1 or Phase < 0.0 then

      Dodaj := - Dodaj;

    end if;

    Phase2 := Phase2 + Dodaj2;
    Phase3 := Phase3 + abs Dodaj2;

    if Phase2 > 5.0 or Phase2 < 1.0 then

      Dodaj2 := - Dodaj2;

    end if;

    Hopa := Integer(2.0+Phase2);

    XSin := Float(Sin(Double(Phase3))) / Phase2;
    XCos := Float(Cos(Double(Phase3))) / Phase2;

    Bufor := Ekran_Obiekt'( Others => Linia'(Others => 0) );

    for b in Wsp_Y loop 

      Fuzz := Integer ( Float(b) / ( 0.001 + Phase ) ) mod Hopa;

      for c in 0 .. Linia'Last/Hopa loop

        Bufor(b)( (a+ Hopa*c) mod ( Linia'Last - Hopa ) + Fuzz ) := 
          Interfaces.Unsigned_8(Fuzz * 50);

      end loop;

      Fuzz := Integer ( Float(b+10) / ( 0.02 + ( 0.09 - Phase ) * 2.0 ) ) 
              mod Hopa;

      for c in 0 .. Linia'Last/Hopa loop

        Bufor(b)( (a+ Hopa*c) mod ( Linia'Last - Hopa ) + Fuzz ) := 
          Interfaces.Unsigned_8(Fuzz * 50);

      end loop;

      MXCos := Integer(Float(b-100)*XCos) - 100;
      MXSin := Integer(Float(b-100)*XSin) + 160;

      for c in 0 .. Linia'Last loop

        X := Integer ( Float(c-160)*XCos ) + MXSin;
        Y := Integer ( Float(c-160)*XSin ) - MXCos;

        if Bufor(b)(c) /= 0 and Tmp(Y)(X) /= 0 then

          Bufor(b)(c) := Tmp(Y)(X);

        end if;

      end loop;

    end loop;

    Ekran(Ekran'Range) := Bufor(Bufor'Range);

  end loop;

  Ada.Calendar.Delays.Delay_For(Standard.duration(10));

end fuzz;