unit filterStackSmasher;
(* ***** BEGIN LICENSE BLOCK *****
 * Copyright (C) 2004 Durand Emmanuel
 * Copyright (C) 2004 Burgel Eric
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Contact :
 *   filters@edurand.com
 *   filters@burgel.com
 *
 * ***** END LICENSE BLOCK ***** *)

{
 eburgel (filters@burgel.com)
}

{ ***********************************************************

  Combine all images from a Stack into a single image.

*************************************************************}

interface
uses
  filter, fparameters, image;

type
  TFilterStackSmasher = class(TFilter)
  public
    constructor Create(); override;
    destructor Destroy; override;
    procedure Run(); override;
    procedure setParameterImages( const aName: String; const aImages: ArrayOfPBitmap32); override;
  private
    parameterImagesIn  : TParameterImages;
    outputparameterImageOut : TParameterImage;
    inImages : ArrayOfPBitmap32 ;
    imageOuts : ArrayOfPBitmap32;
    outImage : PBitmap32;
    procedure _run();
    procedure deleteImages;
  end;

implementation

uses
  imageIO ;

constructor TFilterStackSmasher.Create() ;
begin
  inherited Create() ;
  parameterImagesIn := addParameterImages('inImages', 'inImages') ;
  outputparameterImageOut := addOutputParameterImage('outImage', 'outImage');
  outImage:=nil;
end;

destructor TFilterStackSmasher.Destroy;
begin
  deleteImages;
  inherited;
end;

procedure TFilterStackSmasher.deleteImages;
begin
  image.freeImage(outImage);
end;

procedure TFilterStackSmasher.setParameterImages( const aName: String; const aImages: ArrayOfPBitmap32);
begin
  inherited;
  if aName='inImages' then begin
    deleteImages;
  end;
end;

procedure TFilterStackSmasher.Run();
begin
  inImages := parameterImagesIn.Images ;
  if (inImages<>nil) then begin
    _run();
  end;
end;

procedure TFilterStackSmasher._run();
Var
  i : Integer ;
  imageIn : PBitmap32 ;
  maxWidth : Integer ;
  maxHeight : Integer ;
  color : TColorRec ;
  pSrc : Array of PColor32Array ;
  increments : Array of Array of Integer ;
  pDst : PColor32Array ;
  x, y, y2 : Integer ;
  R, G, B : Cardinal ;
  sR, sG, sB : Cardinal ;
  Nbr : Word ;
  divisor : Cardinal ;
begin

  Nbr := Length(inImages) ;
  divisor := $10000 div Nbr ;

  maxWidth := 0 ;
  maxHeight := 0 ;
  setLength(increments, Nbr) ;
  if outImage = nil then Begin
    // look for the max width and height
    for i := 0 to Nbr-1 do Begin
      setLength(increments[i], maxWidth) ;
      imageIn := inImages[i] ;
      if imageIn.Width > maxWidth Then maxWidth := imageIn.Width ;
      if imageIn.Height > maxHeight Then maxHeight := imageIn.Height ;
    end ;
    outImage := createImage(maxWidth, maxHeight) ;
  End else Begin
    maxWidth := imageOuts[0].Width ;
    maxHeight := imageOuts[0].Height ;
  End ;

  for i := 0 to Nbr-1 do Begin
    setLength(increments[i],maxWidth-1) ;
    For x := 0 to maxWidth-2 do Begin
      increments[i][x] := (inImages[i].Width*(x+1) div maxWidth)-(inImages[i].Width*x div maxWidth) ;
    End ;
  End ;

  setLength(pSrc, Nbr) ;

  // now combining all images
  For y := 0 to maxHeight-1 do Begin
    for i := 0 to Nbr-1 do Begin
      y2 := inImages[i].Height*y div maxHeight ;
      pSrc[i] := scanLine(inImages[i], y2) ;
    End ;
    pDst := scanLine(outImage, y) ;
    For x := 0 to maxWidth-1 do Begin
      sR := 0 ;
      sG := 0 ;
      sB := 0 ;
      for i := 0 to Nbr-1 do Begin
        //x2 := inImages[i].width*x div maxWidth ;
        //R := TColorRec(pSrc[i]^[x2]).Red ;
        //G := TColorRec(pSrc[i]^[x2]).Green ;
        //B := TColorRec(pSrc[i]^[x2]).Blue ;

        R := TColorRec(pSrc[i]^[0]).Red ;
        G := TColorRec(pSrc[i]^[0]).Green ;
        B := TColorRec(pSrc[i]^[0]).Blue ;

        inc(sR, R) ;
        inc(sG, G) ;
        inc(sB, B) ;
        inc(pSrc[i], increments[i][x]) ;
      End ;
      sR := sR * divisor div $10000 ;
      sG := sG * divisor div $10000 ;
      sB := sB * divisor div $10000 ;
      color.Red := sR ;
      color.Green := sG ;
      color.Blue := sB ;
      pDst[0] := Color.value ;
      inc(pDst) ;
    End ;
  End ;

  setOutputParameterImage('outImage',outImage);
end;

end.