/*

% Copyright (C) 2003-2025 GraphicsMagick Group

% Copyright (C) 2002 ImageMagick Studio

% Copyright 1991-1999 E. I. du Pont de Nemours and Company

%

% This program is covered by multiple licenses, which are described in

% Copyright.txt. You should have received a copy of Copyright.txt with this

% package; otherwise see http://www.graphicsmagick.org/www/Copyright.html.

%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                      PPPP    AAA   IIIII  N   N  TTTTT                      %

%                      P   P  A   A    I    NN  N    T                        %

%                      PPPP   AAAAA    I    N N N    T                        %

%                      P      A   A    I    N  NN    T                        %

%                      P      A   A  IIIII  N   N    T                        %

%                                                                             %

%                                                                             %

%                        Methods to Paint on an Image                         %

%                                                                             %

%                                                                             %

%                              Software Design                                %

%                                John Cristy                                  %

%                                 July 1998                                   %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%

*/

/*

 Include declarations.

*/

#include "magick/studio.h"

#include "magick/alpha_composite.h"

#include "magick/color.h"

#include "magick/monitor.h"

#include "magick/paint.h"

#include "magick/pixel_cache.h"

#include "magick/pixel_iterator.h"

#include "magick/render.h"

#include "magick/utility.h"

/*

  Define declarations.

*/

#define FuzzyOpacityMatch(color,target,fuzz) \

  (((color)->opacity == (target)->opacity) && \

   FuzzyColorMatch(color,target,fuzz))

#define MaxStacksize  (((size_t) 1) << 15)

#define Push(up,left,right,delta)                                       \

  {                                                                     \

    if (s >= (segment_stack+MaxStacksize))                              \

      {                                                                 \

        MagickFreeResourceLimitedMemory(unsigned char *,floodplane);    \

        MagickFreeResourceLimitedMemory(SegmentInfo *,segment_stack);   \

        ThrowBinaryException2(DrawError,"SegmentStackOverflow",         \

                              image->filename);                         \

      }                                                                 \

    else                                                                \

      {                                                                 \

        if (((((ptrdiff_t)up)+((ptrdiff_t)delta)) >= 0) &&              \

            ((((ptrdiff_t)up)+((ptrdiff_t)delta)) < (long) image->rows)) \

          {                                                             \

            s->y1=(up);                                                 \

            s->x1=(left);                                               \

            s->x2=(right);                                              \

            s->y2=(delta);                                              \

            s++;                                                        \

          }                                                             \

      }                                                                 \

  }

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   C o l o r F l o o d f i l l I m a g e                                     %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  ColorFloodfill() changes the color value of any pixel that matches

%  target and is an immediate neighbor.  If the method FillToBorderMethod is

%  specified, the color value is changed for any neighbor pixel that does not

%  match the bordercolor member of image.

%

%  By default target must match a particular pixel color exactly.

%  However, in many cases two colors may differ by a small amount.  The

%  fuzz member of image defines how much tolerance is acceptable to

%  consider two colors as the same.  For example, set fuzz to 10 and the

%  color red at intensities of 100 and 102 respectively are now

%  interpreted as the same color for the purposes of the floodfill.

%

%  The format of the ColorFloodfillImage method is:

%

%      MagickPassFail ColorFloodfillImage(Image *image,

%        const DrawInfo *draw_info, const PixelPacket target,

%        const long x_offset,const long y_offset,

%        const PaintMethod method)

%

%  A description of each parameter follows:

%

%    o image: The image.

%

%    o draw_info: The draw info.

%

%    o target: The RGB value of the target color.

%

%    o x,y: The starting location of the operation.

%

%    o method: Choose either FloodfillMethod or FillToBorderMethod.

%

%

*/

MagickExport MagickPassFail ColorFloodfillImage(Image *image,

                                                const DrawInfo *draw_info,

                                                const PixelPacket target,

                                                const long x_offset,

                                                const long y_offset,

                                                const PaintMethod method)

{

  Image

    *pattern;

  int

    skip;

  long

    offset,

    start,

    x1,

    x2,

    y;

  PixelPacket

    color;

  register long

    x;

  register PixelPacket

    *q;

  register SegmentInfo

    *s;

  SegmentInfo

    *segment_stack;

  unsigned char

    *floodplane;

  MagickPassFail

    status=MagickPass;

  /*

    Check boundary conditions.

  */

  assert(image != (Image *) NULL);

  assert(image->signature == MagickSignature);

  assert(draw_info != (DrawInfo *) NULL);

  assert(draw_info->signature == MagickSignature);

  if ((x_offset < 0) || (x_offset >= (long) image->columns))

    return(MagickFail);

  if ((y_offset < 0) || (y_offset >= (long) image->rows))

    return(MagickFail);

  /*

    Set floodfill color.

  */

  if (FuzzyColorMatch(&draw_info->fill,&target,image->fuzz))

    return(MagickFail);

  /*

    The flood-fill algorithm may lock-up if a clip-mask is present

    because the pixels just written may not be what is read later.

    Perhaps we will update the algorithm to respect the clip-mask later.

  */

  if (*ImageGetClipMaskInlined(image))

    {

      ThrowException(&image->exception,DrawError,UnableToFloodFillImageDueToClipMask,image->filename);

      return(MagickFail);

    }

  floodplane=MagickAllocateResourceLimitedClearedArray(unsigned char *,image->columns,image->rows);

  segment_stack=MagickAllocateResourceLimitedArray(SegmentInfo *,MaxStacksize,sizeof(SegmentInfo));

  if ((floodplane== (unsigned char *) NULL) ||

      (segment_stack == (SegmentInfo *) NULL))

    {

      MagickFreeResourceLimitedMemory(unsigned char *, floodplane);

      MagickFreeResourceLimitedMemory(SegmentInfo *, segment_stack);

      ThrowBinaryException3(ResourceLimitError,MemoryAllocationFailed,

                            UnableToFloodfillImage);

    }

  /*

    Push initial segment on stack.

  */

  image->storage_class=DirectClass;

  x=x_offset;

  y=y_offset;

  start=0;

  s=segment_stack;

  Push(y,x,x,1);

  Push((ptrdiff_t)y+1,x,x,-1);

  while (s > segment_stack)

    {

      /*

        Pop segment off stack.

      */

      s--;

      x1=(long) s->x1;

      x2=(long) s->x2;

      offset=(long) s->y2;

      y=(long) s->y1+offset;

      /*

        Recolor neighboring pixels.

      */

      /*

        These two method loops are the same except for the fuzzy-match

        logic.

      */

      if (method == FloodfillMethod)

        {

          q=GetImagePixels(image,0,y,x1+1,1);

          if (q == (PixelPacket *) NULL)

            {

              status=MagickFail;

              break;

            }

          q+=x1;

          for (x=x1; x >= 0; x--)

            {

              if (!FuzzyColorMatch(q,&target,image->fuzz))

                break;

              floodplane[y*image->columns+x]=MagickTrue;

              *q=draw_info->fill;

              q--;

            }

          if (!SyncImagePixels(image))

            {

              status=MagickFail;

              break;

            }

        }

      else /* method == FillToBorderMethod */

        {

          q=GetImagePixels(image,0,y,x1+1,1);

          if (q == (PixelPacket *) NULL)

            {

              status=MagickFail;

              break;

            }

          q+=x1;

          for (x=x1; x >= 0; x--)

            {

              if (FuzzyColorMatch(q,&target,image->fuzz) ||

                  FuzzyColorMatch(q,&draw_info->fill,image->fuzz))

                break;

              floodplane[y*image->columns+x]=MagickTrue;

              *q=draw_info->fill;

              q--;

            }

          if (!SyncImagePixels(image))

            {

              status=MagickFail;

              break;

            }

        }

      skip=x >= x1;

      if (!skip)

        {

          start=x+1;

          if (start < x1)

            Push(y,start,(ptrdiff_t)x1-1,-offset);

          x=x1+1;

        }

      do

        {

          if (!skip)

            {

              if (x < (long) image->columns)

                {

                  /*

                    These two method loops are the same except for the

                    fuzzy-match logic.

                  */

                  if (method == FloodfillMethod)

                    {

                      q=GetImagePixels(image,x,y,image->columns-x,1);

                      if (q == (PixelPacket *) NULL)

                        {

                          status=MagickFail;

                          break;

                        }

                      for ( ; x < (long) image->columns; x++)

                        {

                          if (!FuzzyColorMatch(q,&target,image->fuzz))

                            break;

                          floodplane[y*image->columns+x]=MagickTrue;

                          *q=draw_info->fill;

                          q++;

                        }

                      if (!SyncImagePixels(image))

                        {

                          status=MagickFail;

                          break;

                        }

                    }

                  else /* method == FillToBorderMethod */

                    {

                      q=GetImagePixels(image,x,y,image->columns-x,1);

                      if (q == (PixelPacket *) NULL)

                        {

                          status=MagickFail;

                          break;

                        }

                      for ( ; x < (long) image->columns; x++)

                        {

                          if (FuzzyColorMatch(q,&target,image->fuzz) ||

                              FuzzyColorMatch(q,&draw_info->fill,image->fuzz))

                            break;

                          floodplane[y*image->columns+x]=True;

                          *q=draw_info->fill;

                          q++;

                        }

                      if (!SyncImagePixels(image))

                        {

                          status=MagickFail;

                          break;

                        }

                    }

                }

              Push(y,start, (ptrdiff_t)x-1,offset);

              if (x > ((ptrdiff_t)x2+1))

                Push(y, (ptrdiff_t)x2+1, (ptrdiff_t)x-1,-offset);

            }

          skip=False;

          x++;

          if (x <= x2)

            {

              /*

                These two method loops are the same except for the

                fuzzy-match logic.

              */

              if (method == FloodfillMethod)

                {

                  q=GetImagePixels(image,x,y,x2-x+1,1);

                  if (q == (PixelPacket *) NULL)

                    {

                      status=MagickFail;

                      break;

                    }

                  for ( ; x <= x2; x++)

                    {

                      if (FuzzyColorMatch(q,&target,image->fuzz))

                        break;

                      q++;

                    }

                }

              else /* method == FillToBorderMethod */

                {

                  q=GetImagePixels(image,x,y,x2-x+1,1);

                  if (q == (PixelPacket *) NULL)

                    {

                      status=MagickFail;

                      break;

                    }

                  for ( ; x <= x2; x++)

                    {

                      if (!FuzzyColorMatch(q,&target,image->fuzz) &&

                          !FuzzyColorMatch(q,&draw_info->fill,image->fuzz))

                        break;

                      q++;

                    }

                }

            }

          start=x;

        } while (x <= x2);

    }

  pattern=draw_info->fill_pattern;

  if (pattern == (Image *) NULL)

    {

      /*

        Tile fill color onto floodplane.

      */

      if (status == MagickPass)

        {

#if defined(HAVE_OPENMP)

#  pragma omp parallel for schedule(static,64) shared(status)

#endif

          for (y=0; y < (long) image->rows; y++)

            {

              PixelPacket

                * restrict p;

              if (status == MagickFail)

                continue;

              p=GetImagePixels(image,0,y,image->columns,1);

              if (p == (PixelPacket *) NULL)

                {

                  goto tile_color_fail;

                }

              for (x=0; x < (long) image->columns; x++)

                {

                  if (floodplane[y*image->columns+x])

                    *p=draw_info->fill;

                  p++;

                }

              if (!SyncImagePixels(image))

                {

                  goto tile_color_fail;

                }

              /* Continue loop processing */

              continue;

              /* There was a problem */

            tile_color_fail:;

              status=MagickFail;

#if defined(HAVE_OPENMP)

#  pragma omp flush (status)

#endif

            }

        }

    }

  else

    {

      /*

        Tile image onto floodplane.

      */

      if (status == MagickPass)

        {

#if defined(HAVE_OPENMP)

#  pragma omp parallel for schedule(static,64) shared(status)

#endif

          for (y=0; y < (long) image->rows; y++)

            {

              PixelPacket

                * restrict p;

              if (status == MagickFail)

                continue;

              p=GetImagePixels(image,0,y,image->columns,1);

              if (p == (PixelPacket *) NULL)

                goto tile_pattern_fail;

              for (x=0; x < (long) image->columns; x++)

                {

                  if (floodplane[y*image->columns+x])

                    {

                      if (!AcquireOnePixelByReference(pattern,

                                                      &color,

                                                      (long) ((unsigned long)

                                                              (x-pattern->tile_info.x) %

                                                              pattern->columns),

                                                      (long) ((unsigned long)

                                                              (y-pattern->tile_info.y) %

                                                              pattern->rows),

                                                      &image->exception))

                        goto tile_pattern_fail;

                      if (!pattern->matte)

                        color.opacity=OpaqueOpacity;

                      if (color.opacity != TransparentOpacity)

                        AlphaCompositePixel(p,&color,color.opacity,p,p->opacity);

                    }

                  p++;

                } /* for x ... */

              if (!SyncImagePixels(image))

                goto tile_pattern_fail;

              /* Continue loop processing */

              continue;

              /* There was a problem */

            tile_pattern_fail:;

              status=MagickFail;

#if defined(HAVE_OPENMP)

#  pragma omp flush (status)

#endif

            } /* for y ... */

        } /* if status ... */

    }

  MagickFreeResourceLimitedMemory(SegmentInfo *, segment_stack);

  MagickFreeResourceLimitedMemory(unsigned char *, floodplane);

  return(status);

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   M a t t e F l o o d f i l l I m a g e                                     %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  MatteFloodfill() changes the transparency value of any pixel that matches

%  target and is an immediate neighbor.  If the method FillToBorderMethod

%  is specified, the transparency value is changed for any neighbor pixel

%  that does not match the bordercolor member of image.

%

%  By default target must match a particular pixel transparency exactly.

%  However, in many cases two transparency values may differ by a

%  small amount.  The fuzz member of image defines how much tolerance is

%  acceptable to consider two transparency values as the same.  For example,

%  set fuzz to 10 and the opacity values of 100 and 102 respectively are

%  now interpreted as the same value for the purposes of the floodfill.

%

%  The format of the MatteFloodfillImage method is:

%

%      unsigned int MatteFloodfillImage(Image *image,const PixelPacket target,

%        const unsigned int opacity,const long x_offset,const long y_offset,

%        const PaintMethod method)

%

%  A description of each parameter follows:

%

%    o image: The image.

%

%    o target: The RGB value of the target color.

%

%    o opacity: The level of transparency: 0 is fully opaque and MaxRGB is

%      fully transparent.

%

%    o x,y: The starting location of the operation.

%

%    o method:  Choose either FloodfillMethod or FillToBorderMethod.

%

%

*/

MagickExport MagickPassFail MatteFloodfillImage(Image *image,

  const PixelPacket target,const unsigned int opacity,const long x_offset,

  const long y_offset,const PaintMethod method)

{

  int

    skip;

  long

    offset,

    start,

    x1,

    x2,

    y;

  register long

    x;

  register PixelPacket

    *q;

  register SegmentInfo

    *s;

  SegmentInfo

    *segment_stack;

  void

    *floodplane = (void *) NULL; /* Only to make common Push macro happy */

  MagickPassFail

    status=MagickPass;

  /*

    Check boundary conditions.

  */

  assert(image != (Image *) NULL);

  assert(image->signature == MagickSignature);

  if ((x_offset < 0) || (x_offset >= (long) image->columns))

    return(MagickFail);

  if ((y_offset < 0) || (y_offset >= (long) image->rows))

    return(MagickFail);

  if (target.opacity == opacity)

    return(MagickFail);

  q=GetImagePixels(image,x_offset,y_offset,1,1);

  if (q == (PixelPacket *) NULL)

    return(MagickFail);

  if (q->opacity == opacity)

    return(MagickFail);

  /*

    The flood-fill algorithm may lock-up if a clip-mask is present

    because the pixels just written may not be what is read later.

    Perhaps we will update the algorithm to respect the clip-mask later.

  */

  if (*ImageGetClipMaskInlined(image))

    {

      ThrowException(&image->exception,DrawError,UnableToFloodFillImageDueToClipMask,image->filename);

      return(MagickFail);

    }

  /*

    Allocate segment stack.

  */

  segment_stack=MagickAllocateResourceLimitedArray(SegmentInfo *,MaxStacksize,sizeof(SegmentInfo));

  if (segment_stack == (SegmentInfo *) NULL)

    ThrowBinaryException3(ResourceLimitError,MemoryAllocationFailed,

      UnableToFloodfillImage);

  /*

    Push initial segment on stack.

  */

  (void) SetImageType(image,TrueColorMatteType);

  x=x_offset;

  y=y_offset;

  start=0;

  s=segment_stack;

  Push(y,x,x,1);

  Push((ptrdiff_t)y+1,x,x,-1);

  while (s > segment_stack)

  {

    /*

      Pop segment off stack.

    */

    s--;

    x1=(long) s->x1;

    x2=(long) s->x2;

    offset=(long) s->y2;

    y=(long) s->y1+offset;

    /*

      Recolor neighboring points.

    */

    q=GetImagePixels(image,0,y,image->columns,1);

    if (q == (PixelPacket *) NULL)

      {

        status=MagickFail;

        break;

      }

    q+=x1;

    for (x=x1; x >= 0; x--)

    {

      if (method == FloodfillMethod)

        {

          if (!FuzzyOpacityMatch(q,&target,image->fuzz))

            break;

        }

      else

        if (FuzzyOpacityMatch(q,&target,image->fuzz) || (q->opacity == opacity))

          break;

      q->opacity=opacity;

      q--;

    }

    if (!SyncImagePixels(image))

      {

        status=MagickFail;

        break;

      }

    skip=x >= x1;

    if (!skip)

      {

        start=x+1;

        if (start < x1)

          Push(y,start, (ptrdiff_t)x1-1,-offset);

        x=x1+1;

      }

    do

    {

      if (!skip)

        {

          q=GetImagePixels(image,0,y,image->columns,1);

          if (q == (PixelPacket *) NULL)

            {

              status=MagickFail;

              break;

            }

          q+=x;

          for ( ; x < (long) image->columns; x++)

          {

            if (method == FloodfillMethod)

              {

                if (!FuzzyOpacityMatch(q,&target,image->fuzz))

                  break;

              }

            else

              if (FuzzyOpacityMatch(q,&target,image->fuzz) ||

                  (q->opacity == opacity))

                break;

            q->opacity=opacity;

            q++;

          }

          if (!SyncImagePixels(image))

            {

              status=MagickFail;

              break;

            }

          Push(y,start, (ptrdiff_t)x-1,offset);

          if (x > ((ptrdiff_t)x2+1))

            Push(y, (ptrdiff_t)x2+1, (ptrdiff_t)x-1,-offset);

        }

      skip=False;

      q=GetImagePixels(image,0,y,image->columns,1);

      if (q == (PixelPacket *) NULL)

        {

          status=MagickFail;

          break;

        }

      q+=x;

      for (x++; x <= x2; x++)

      {

        q++;

        if (method == FloodfillMethod)

          {

            if (FuzzyOpacityMatch(q,&target,image->fuzz))

              break;

          }

        else

          if (!FuzzyOpacityMatch(q,&target,image->fuzz) &&

              (q->opacity != opacity))

            break;

      }

      start=x;

    } while (x <= x2);

  }

  MagickFreeResourceLimitedMemory(SegmentInfo*, segment_stack);

  return(status);

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%     O p a q u e I m a g e                                                   %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  OpaqueImage() changes any pixel that matches color with the color

%  defined by fill.

%

%  By default color must match a particular pixel color exactly.  However,

%  in many cases two colors may differ by a small amount.  Fuzz defines

%  how much tolerance is acceptable to consider two colors as the same.

%  For example, set fuzz to 10 and the color red at intensities of 100 and

%  102 respectively are now interpreted as the same color.

%

%  The format of the OpaqueImage method is:

%

%      unsigned int OpaqueImage(Image *image,const PixelPacket target,

%        const PixelPacket fill)

%

%  A description of each parameter follows:

%

%    o image: The image.

%

%    o target: The RGB value of the target color.

%

%    o fill: The replacement color.

%

%

*/

typedef struct _OpaqueImageOptions_t

{

  double fuzz;

  PixelPacket fill;

  PixelPacket target;

} OpaqueImageOptions_t;

static MagickPassFail

OpaqueImageCallBack(void *mutable_data,         /* User provided mutable data */

                      const void *immutable_data, /* User provided immutable data */

                      Image * restrict image,               /* Modify image */

                      PixelPacket * restrict pixels,        /* Pixel row */

                      IndexPacket * restrict indexes,       /* Pixel row indexes */

                      const long npixels,         /* Number of pixels in row */

                      ExceptionInfo *exception)   /* Exception report */

{

  const OpaqueImageOptions_t

    options = *((const OpaqueImageOptions_t *) immutable_data);

  register long

    i;

  ARG_NOT_USED(mutable_data);

  ARG_NOT_USED(image);

  ARG_NOT_USED(indexes);

  ARG_NOT_USED(exception);

  if (options.fuzz == 0.0)

    {

      for (i=0; i < npixels; i++)

        {

          if (ColorMatch(&pixels[i],&options.target))

            pixels[i]=options.fill;

        }

    }

  else

    {

      for (i=0; i < npixels; i++)

        {

          if (FuzzyColorMatch(&pixels[i],&options.target,options.fuzz))

            pixels[i]=options.fill;

        }

    }

  return MagickPass;

}

MagickExport MagickPassFail

OpaqueImage(Image *image,const PixelPacket target,const PixelPacket fill)

{

#define OpaqueImageText "[%s] Setting opaque color..."

  OpaqueImageOptions_t

    options;

  MagickPassFail

    status=MagickPass;

  MagickBool

    is_monochrome = image->is_monochrome,

    is_grayscale = image->is_grayscale;

  assert(image != (Image *) NULL);

  assert(image->signature == MagickSignature);

  options.fuzz=image->fuzz;

  options.fill=fill;

  options.target=target;

  /*

    Assure that image type is promoted as required based on color

  */

  if ((is_grayscale || IsGrayColorspace(image->colorspace)) && !IsGray(fill))

    {

      if ((is_monochrome) && !IsBlackPixel(fill) && !IsWhitePixel(fill))

        is_monochrome = MagickFalse;

      is_grayscale = MagickFalse;

    }

  /*

    Make image color opaque.

  */

  if (image->storage_class == PseudoClass)

    {

      assert(image->colormap != (PixelPacket *) NULL);

      (void) OpaqueImageCallBack(0,&options,image,image->colormap,

                                 (IndexPacket *) NULL,image->colors,

                                 &image->exception);

      status &= SyncImage(image);

    }

  else

    {

      status=PixelIterateMonoModify(OpaqueImageCallBack,NULL,

                                    OpaqueImageText,NULL,&options,0,0,

                                    image->columns,image->rows,

                                    image,&image->exception);

    }

  image->is_monochrome = is_monochrome;

  image->is_grayscale = is_grayscale;

  return(status);

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%     T r a n s p a r e n t I m a g e                                         %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  TransparentImage() changes the opacity value associated with any pixel

%  that matches color to the value defined by opacity.

%

%  By default color must match a particular pixel color exactly.  However,

%  in many cases two colors may differ by a small amount.  Fuzz defines

%  how much tolerance is acceptable to consider two colors as the same.

%  For example, set fuzz to 10 and the color red at intensities of 100 and

%  102 respectively are now interpreted as the same color.

%

%  The format of the TransparentImage method is:

%

%      unsigned int TransparentImage(Image *image,const PixelPacket target,

%        const unsigned int opacity)

%

%  A description of each parameter follows:

%

%    o image: The image.

%

%    o target: The RGB value of the target color.

%

%    o opacity: The replacement opacity value.

%

%

*/

typedef struct _TransparentImageOptions_t

{

  double fuzz;

  PixelPacket target;

  unsigned int opacity;

} TransparentImageOptions_t;

static MagickPassFail

TransparentImageCallBack(void *mutable_data,         /* User provided mutable data */

                         const void *immutable_data, /* User provided immutable data */

                         Image * restrict image,               /* Modify image */

                         PixelPacket * restrict pixels,        /* Pixel row */

                         IndexPacket * restrict indexes,       /* Pixel row indexes */

                         const long npixels,         /* Number of pixels in row */

                         ExceptionInfo *exception)   /* Exception report */

{

  const TransparentImageOptions_t

    options = *((const TransparentImageOptions_t *) immutable_data);

  const MagickBool

    clear_matte = (!image->matte);

  register long

    i;

  ARG_NOT_USED(mutable_data);

  ARG_NOT_USED(image);

  ARG_NOT_USED(indexes);

  ARG_NOT_USED(exception);

  if (options.fuzz == 0.0)

    {

      for (i=0; i < npixels; i++)

        {

          if (ColorMatch(&pixels[i],&options.target))

            pixels[i].opacity=options.opacity;

          else if (clear_matte)

            pixels[i].opacity=OpaqueOpacity;

        }

    }

  else

    {

      for (i=0; i < npixels; i++)

        {

          if (FuzzyColorMatch(&pixels[i],&options.target,options.fuzz))

            pixels[i].opacity=options.opacity;

          else if (clear_matte)

            pixels[i].opacity=OpaqueOpacity;

        }

    }

  return MagickPass;

}

MagickExport MagickPassFail

TransparentImage(Image *image,const PixelPacket target,

                 const unsigned int opacity)

{

#define TransparentImageText "[%s] Setting transparent color...  "

  TransparentImageOptions_t

    options;

  MagickPassFail

    status=MagickPass;

  /*

    Make image color transparent.

  */

  assert(image != (Image *) NULL);

  assert(image->signature == MagickSignature);

  options.fuzz=image->fuzz;

  options.opacity=opacity;

  options.target=target;

  if (image->storage_class == PseudoClass)

    {

      assert(image->colormap != (PixelPacket *) NULL);

      (void) TransparentImageCallBack(0,&options,image,image->colormap,

                                 (IndexPacket *) NULL,image->colors,

                                 &image->exception);

      status &= SyncImage(image);

    }

  else

    {

      status=PixelIterateMonoModify(TransparentImageCallBack,NULL,

                                    TransparentImageText,NULL,&options,0,0,

                                    image->columns,image->rows,

                                    image,&image->exception);

    }

  image->matte=MagickTrue;

  return(status);

}