gimp/app/gimpdrawable-invert.c

/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "appenv.h"
#include "drawable.h"
#include "interface.h"
#include "invert.h"
#include "gimage.h"
#include "gimplut.h"
#include "lut_funcs.h"

#include "libgimp/gimpintl.h"

static void       invert (GimpDrawable *);
static Argument * invert_invoker (Argument *);


void
image_invert (GImage *gimage)
{
  GimpDrawable *drawable;
  Argument *return_vals;
  int nreturn_vals;

  drawable = gimage_active_drawable (gimage);

  if (drawable_indexed (drawable))
    {
      g_message (_("Invert does not operate on indexed drawables."));
      return;
    }

  return_vals = procedural_db_run_proc ("gimp_invert",
					&nreturn_vals,
					PDB_DRAWABLE, drawable_ID (drawable),
					PDB_END);

  if (!return_vals || return_vals[0].value.pdb_int != PDB_SUCCESS)
    g_message (_("Invert operation failed."));

  procedural_db_destroy_args (return_vals, nreturn_vals);
}


/*  Inverter  */

static void
invert (GimpDrawable *drawable)
{
  PixelRegion srcPR, destPR;
  int x1, y1, x2, y2;
  GimpLut *lut;

  lut = invert_lut_new(gimp_drawable_bytes(drawable));

  drawable_mask_bounds (drawable, &x1, &y1, &x2, &y2);
  pixel_region_init (&srcPR, drawable_data (drawable), x1, y1, (x2 - x1), (y2 - y1), FALSE);
  pixel_region_init (&destPR, drawable_shadow (drawable), x1, y1, (x2 - x1), (y2 - y1), TRUE);

  pixel_regions_process_parallel((p_func)gimp_lut_process, lut, 
				 2, &srcPR, &destPR);

  gimp_lut_free(lut);

  drawable_merge_shadow (drawable, TRUE);
  drawable_update (drawable, x1, y1, (x2 - x1), (y2 - y1));
}

/*  ------------------------------------------------------------------  */
/*  ----------------- The invert procedure definition ----------------  */
/*  ------------------------------------------------------------------  */

ProcArg invert_args[] =
{
  { PDB_DRAWABLE,
    "drawable",
    "the drawable"
  }
};

ProcRecord invert_proc =
{
  "gimp_invert",
  "Invert the contents of the specified drawable",
  "This procedure inverts the contents of the specified drawable.  Each intensity channel is inverted independently.  The inverted intensity is given as inten' = (255 - inten).  Indexed color drawables are not valid for this operation.",
  "Spencer Kimball & Peter Mattis",
  "Spencer Kimball & Peter Mattis",
  "1995-1996",
  PDB_INTERNAL,

  /*  Input arguments  */
  1,
  invert_args,

  /*  Output arguments  */
  0,
  NULL,

  /*  Exec method  */
  { { invert_invoker } },
};


static Argument *
invert_invoker (args)
     Argument *args;
{
  int success = TRUE;
  int int_value;
  GImage *gimage;
  GimpDrawable *drawable;

  drawable = NULL;

  /*  the drawable  */
  if (success)
    {
      int_value = args[0].value.pdb_int;
      drawable = drawable_get_ID (int_value);
      if (drawable == NULL)                                        
        success = FALSE;
      else
        gimage = drawable_gimage (drawable);
    }
  /*  make sure the drawable is not indexed color  */
  if (success)
    success = ! drawable_indexed (drawable);

  if (success)
    invert (drawable);

  return procedural_db_return_args (&invert_proc, success);
}