{
     Apophysis Copyright (C) 2001-2004 Mark Townsend
     Apophysis Copyright (C) 2005-2006 Ronald Hordijk, Piotr Borys, Peter Sdobnov
     Apophysis Copyright (C) 2007-2008 Piotr Borys, Peter Sdobnov
     
     Apophysis "3D hack" Copyright (C) 2007-2008 Peter Sdobnov
     Apophysis "7X" Copyright (C) 2009-2010 Georg Kiehne

     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
}

unit varPostCurl;

interface

uses
  BaseVariation, XFormMan;

const
  variation_name = 'post_curl';
  num_vars = 2;

 {$ifdef Apo7X64}
{$else}
  {$define _ASM_}
{$endif}

type
  TVariationPostCurl = class(TBaseVariation)
  private
    c1, c2, c2x2: double;

    procedure CalcZeroC2;
    procedure CalcZeroC1;
    procedure CalcZeroC2C1;
  public
    class function GetName: string; override;
    class function GetInstance: TBaseVariation; override;

    function GetNrVariables: integer; override;
    function GetVariableNameAt(const Index: integer): string; override;

    function SetVariable(const Name: string; var value: double): boolean; override;
    function GetVariable(const Name: string; var value: double): boolean; override;
    function ResetVariable(const Name: string): boolean; override;

    procedure Prepare; override;
    procedure CalcFunction; override;
	  procedure GetCalcFunction(var f: TCalcFunction); override;
  end;

implementation

uses
  Math;

// TVariationPostCurl

///////////////////////////////
procedure TVariationPostCurl.Prepare;
begin
	// AV:	fixed - it's wrong when vvar <> 1
  //c1 := c1 * VVAR;	 
  //c2 := c2 * VVAR;
  c2x2 := 2 * c2;
end;

////////////////////////////////////////////////////////////////////
procedure TVariationPostCurl.GetCalcFunction(var f: TCalcFunction);
begin
  if IsZero(c1) then begin
    if IsZero(c2) then
      f := CalcZeroC2C1
    else
      f := CalcZeroC1
  end
  else begin
    if IsZero(c2) then
      f := CalcZeroC2
    else
      f := CalcFunction
  end;
end;

///////////////////////////////////////////////////////////////////////////////
procedure TVariationPostCurl.CalcFunction;
{$ifndef _ASM_}
var
  x, y, r, re, im: double;
begin
  x := FPx^;
  y := FPy^;

  re := 1 + c1 * x + c2 * (sqr(x) - sqr(y));
  im := c1 * y + c2x2 * x * y;

  r := vvar / (sqr(re) + sqr(im));
  FPx^ := (x * re + y * im) * r;
  FPy^ := (y * re - x * im) * r;
{$else}  
asm
    mov     edx, [eax + FTx]

    fld     qword ptr [edx + 24] // FPy
    fld     qword ptr [edx + 16]     // FPx
    fld     st(1)
    fmul    st, st(1)
    fmul    qword ptr [eax + c2x2]
    fld     st(2)
    fmul    qword ptr [eax + c1]
    faddp
    fld     st(2)
    fmul    st, st
    fld     st(2)
    fmul    st, st
    fsubrp
    fmul    qword ptr [eax + c2]
    fld1
    faddp
    fld     st(2)
    fmul    qword ptr [eax + c1]
    faddp

    fld     st(1)
    fmul    st, st
    fld     st(1)
    fmul    st, st
    faddp
    fdivr   qword ptr [eax + vvar]

    fld     st(3)
    fmul    st, st(2)
    fld     st(5)
    fmul    st, st(4)
    faddp
    fmul    st, st(1)
    
    fstp    qword ptr [edx + 16] // FPx

    fxch    st(4)
    fmulp
    fxch    st(2)
    fmulp
    fsubp
    fmulp
   
    fstp    qword ptr [edx + 24] // FPy
{$endif}  
end;
///////////////////////////////////////////////////////////////////////////////
procedure TVariationPostCurl.CalcZeroC2;  // AV: Mobius case
{$ifndef _ASM_}
var
  r, x, y: double;
  re, im: double;
begin
  x := FPx^;
  y := FPy^;
  re := 1 + c1 * x;
  im :=     c1 * y;

  r := vvar / (sqr(re) + sqr(im));

  FPx^ := (x*re + y*im) * r;
  FPy^ := (y*re - x*im) * r;
  //FPz^ := vvar * FPz^;
{$else}
asm
    mov     edx, [eax + FTx]

    fld     qword ptr [edx + 24] // FPy
    fld     qword ptr [edx + 16]     // FPx
    fld     st(1)
    fld     qword ptr [eax + c1]
    fmul    st(1), st
    fmul    st, st(2)
    fld1
    faddp

    fld     st(1)
    fmul    st, st
    fld     st(1)
    fmul    st, st
    faddp
    fdivr   qword ptr [eax + vvar]

    fld     st(3)
    fmul    st, st(2)
    fld     st(5)
    fmul    st, st(4)
    faddp
    fmul    st, st(1)

    fstp    qword ptr [edx + 16] // FPx

    fxch    st(4)
    fmulp
    fxch    st(2)
    fmulp
    fsubp
    fmulp

    fstp    qword ptr [edx + 24] // FPy
{$endif}
end;

procedure TVariationPostCurl.CalcZeroC1;
{$ifndef _ASM_}
var
  r, x, y: double;
  re, im: double;
begin
  x := FPx^;
  y := FPy^;
  re := 1 + c2*(sqr(x) - sqr(y));
  im :=   c2x2 * x * y;

  r := vvar / (sqr(re) + sqr(im));

  FPx^ := (x*re + y*im) * r;
  FPy^ := (y*re - x*im) * r;

{$else}
asm
    mov     edx, [eax + FTx]

    fld     qword ptr [edx + 24] // FPy
    fld     qword ptr [edx + 16]     // FPx
    fld     st(1)
    fmul    st, st(1)
    fmul    qword ptr [eax + c2x2]
    fld     st(2)
    fmul    st, st
    fld     st(2)
    fmul    st, st
    fsubrp
    fmul    qword ptr [eax + c2]
    fld1
    faddp

    fld     st(1)
    fmul    st, st
    fld     st(1)
    fmul    st, st
    faddp
    fdivr   qword ptr [eax + vvar]

    fld     st(3)
    fmul    st, st(2)
    fld     st(5)
    fmul    st, st(4)
    faddp
    fmul    st, st(1)

    fstp    qword ptr [edx + 16]	// FPx

    fxch    st(4)
    fmulp
    fxch    st(2)
    fmulp
    fsubp
    fmulp

    fstp    qword ptr [edx + 24] // FPy
    //fwait
{$endif}
end;

procedure TVariationPostCurl.CalcZeroC2C1;  // AV: linear case
{$ifndef _ASM_}
var
  r: double;
begin
  FPx^ := vvar * FPx^;
  FPy^ := vvar * FPy^;
{$else}
asm
    fld     qword ptr [eax + vvar]
    mov     edx, [eax + FTx]
    fld     qword ptr [edx + 16]      // FPx
    fmul    st, st(1)
    fstp    qword ptr [edx + 16]

    fld     qword ptr [edx + 24]  // FPy
    fmulp
    fstp    qword ptr [edx + 24]
    //fwait
{$endif}
end;


class function TVariationPostCurl.GetInstance: TBaseVariation;
begin
  Result := TVariationPostCurl.Create;
end;

///////////////////////////////////////////////////////////////////////////////
class function TVariationPostCurl.GetName: string;
begin
  Result := variation_name;
end;

///////////////////////////////////////////////////////////////////////////////
function TVariationPostCurl.GetVariableNameAt(const Index: integer): string;
begin
  case Index of
    0: Result := 'post_curl_c1';
    1: Result := 'post_curl_c2';
  else
    Result := '';
  end
end;

///////////////////////////////////////////////////////////////////////////////
function TVariationPostCurl.SetVariable(const Name: string; var value: double): boolean;
begin
  Result := False;
  if Name = 'post_curl_c1' then begin
    c1 := value;
    Result := True;
  end
  else if Name = 'post_curl_c2' then begin
    c2 := value;
    Result := True;
  end;
end;

function TVariationPostCurl.ResetVariable(const Name: string): boolean;
begin
  Result := False;
  if Name = 'post_curl_c1' then begin
    c1 := 0;
    Result := True;
  end
  else if Name = 'post_curl_c2' then begin
    c2 := 0;
    Result := True;
  end;
end;

///////////////////////////////////////////////////////////////////////////////
function TVariationPostCurl.GetNrVariables: integer;
begin
  Result := num_vars;
end;

///////////////////////////////////////////////////////////////////////////////
function TVariationPostCurl.GetVariable(const Name: string; var value: double): boolean;
begin
  Result := False;
  if Name = 'post_curl_c1' then begin
    value := c1;
    Result := True;
  end
  else if Name = 'post_curl_c2' then begin
    value := c2;
    Result := True;
  end;
end;

///////////////////////////////////////////////////////////////////////////////
initialization
  RegisterVariation(TVariationClassLoader.Create(TVariationPostCurl), false, false);
end.