(* ---------------------------- WAV3D.PAS ------------------------- *)
(* Coded bye Jare/Iguana in 1993. Want more comment's? Write'em!    *)
(* Use this as you like; you're going to anyway, so who cares.      *)
(* But remember: proper crediting and greeting rules.               *)

USES Dos;

VAR
  reg : Registers;

FUNCTION GetKey: WORD;
BEGIN
  reg.AH := 0;
  Intr($16, reg);
  GetKey := reg.AX
END;

FUNCTION TestKey: BOOLEAN;
BEGIN
  reg.AH := 1;
  Intr($16, reg);
  TestKey := (reg.Flags AND FZero) = 0
END;

PROCEDURE VSync;
BEGIN
  WHILE (Port[$3DA] AND 8) =  8 DO;
  WHILE (Port[$3DA] AND 8) <> 8 DO;
END;

  (* -------------------- *)

TYPE
  tScrBuf = ARRAY [0..200-1,0..320-1] OF BYTE;
  tScrWBuf = ARRAY [0..200-1,0..160-1] OF WORD;
VAR
  VGABuf : TScrBuf ABSOLUTE $A000:0000;
  VGAWBuf : TScrWBuf ABSOLUTE $A000:0000;

VAR
  i,j,k,n : INTEGER; { Shitty global vars. This is just a prototype!}
  r, d, v, a : REAL;
  c, lasth, limit : WORD;
  highest : ARRAY [0..159] OF BYTE;

TYPE
  TWavBuf = ARRAY [0..63, 0..127] OF BYTE;
  TLandBuf = ARRAY [0..31, 0..159] OF BYTE;

VAR
  Wb : TWavBuf;
  fw : FILE OF TWavBuf;
  lb : TLandBuf;
  fl : FILE OF TLandBuf;

CONST
  MaxRadius = 159.0*159.0 + 31.0*31.0;
  s159      = 159.0*159.0;
  s31       = 31.0*31.0;

PROCEDURE GenerateLand;
BEGIN
  FOR i := 0 TO 31 DO
    FOR j := 0 TO 159 DO BEGIN
      lb[i,j] := ROUND(SQRT((i+0.0)*i/s31 +
                            (j+0.0)*j/s159)*127{/SQRT(2)});
      IF lb[i,j] > 127 THEN
        lb[i,j] := 127
    END;
  Assign(fl, 'land.dat');             { Escritura de la tabla. }
  ReWrite(fl);
  Write(fl, lb);
  Close(fl)
END;

PROCEDURE GenerateWav;
BEGIN
  FOR j := 0 TO 63 DO                  { Generacion de la tabla. }
    FOR i := 0 TO 127{319} DO BEGIN
      r := (i+1) * 5.0 * PI / 320.0;
      d := j * PI / 32.0;
      v := ((Sin(r - d)-Sin(-d)) / r )
           - (Cos(r-d)/2);
      a := Cos(i*PI/2/128);
      k := 100 + ROUND(100.0 * a * a * v);
      Wb[j, i] := BYTE(k);
      VGABuf[k,i] := 150 + j
    END;
  Assign(fw, 'waves.dat');            { Grabaciвn de la tabla. }
  ReWrite(fw);
  Write(fw, wb);
  Close(fw)
END;

VAR
  par, pcod : INTEGER;

BEGIN
  VAL(ParamStr(1), par, pcod);
  IF pcod = 0 THEN BEGIN
    ASM
      MOV AX,13h
      INT 10h
    END;
    IF (par AND 1) = 1 THEN
      GenerateLand;
      IF (par AND 2) = 2 THEN
        GenerateWav;
  END ELSE BEGIN
    WriteLn('3D Wave bye Jare/Iguana (Pascal prototype & .DAT',
            ' generator).'#13#10,
            '   Type "WAV3D 3" to generate files. From then on just',
            ' type "WAV3D 0",'#13#10,
            '     which will use the created files.');
    HALT
  END;

  Assign(fl, 'land.dat');             { Lectura de la tabla. }
  ReSet(fl);
  Read(fl, lb);
  Close(fl);

  Assign(fw, 'waves.dat');             { Lectura de la tabla. }
  ReSet(fw);
  Read(fw, wb);
  Close(fw);

  FillChar(VGABuf,  64000, 0);
  FillChar(highest, 160, 199);

  WHILE TestKey DO
    GetKey;

  ASM
    MOV CX,64
    MOV DX,03C8h
    MOV AL,64
    OUT DX,AL
    INC DX
    XOR AL,AL
  @@l:
    OUT DX,AL
    OUT DX,AL
    OUT DX,AL
    INC AL
    LOOP @@l
  END;

  k := 0;
  REPEAT
    n := (k + 1) MOD 64;
    FOR j := 0 TO 159 DO BEGIN
      c := 63+64;
      lasth := 199;
      FOR i := 31 DOWNTO 0 DO BEGIN
        limit := 56+i+Wb[n,Lb[i,j]];
        WHILE lasth > limit DO BEGIN
          VGABuf[lasth,j+160] := c;
          VGABuf[lasth,159-j] := c;
          DEC(lasth)
        END;
        DEC(c)
      END;
      FOR i := 0 TO 31 DO BEGIN
        limit := 55-i+Wb[n,Lb[i,j]];
        WHILE lasth > limit DO BEGIN
          VGABuf[lasth,j+160] := c;
          VGABuf[lasth,159-j] := c;
          DEC(lasth)
        END;
        DEC(c)
      END;
      FOR i := lasth DOWNTO highest[j] DO BEGIN
        VGABuf[i, j+160] := 0;
        VGABuf[i, 159-j] := 0
      END;
      highest[j] := lasth
    END;
    VSync;
    k := n
  UNTIL TestKey;

  GetKey;
  ASM
    MOV AX,3h
    INT 10h
  END
END.