gimp/plug-ins/common/ripple.c

/* Ripple --- image filter plug-in for The Gimp image manipulation program
 * Copyright (C) 1997 Brian Degenhardt
 *
 * 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.
 *
 * Please direct all comments, questions, bug reports  etc to Brian Degenhardt
 * bdegenha@ucsd.edu
 *
 * You can contact the original The Gimp authors at gimp@xcf.berkeley.edu
 */
#include "config.h"

#include <stdio.h>
#include <stdlib.h>

#include <gtk/gtk.h>

#include <libgimp/gimp.h>
#include <libgimp/gimpui.h>

#include "libgimp/stdplugins-intl.h"


/* Some useful macros */
#define SCALE_WIDTH     200
#define TILE_CACHE_SIZE  16

#define HORIZONTAL 0
#define VERTICAL   1

#define SMEAR 0
#define WRAP  1
#define BLACK 2

#define SAWTOOTH 0
#define SINE     1

typedef struct
{
  gint period;
  gint amplitude;
  gint orientation;
  gint edges;
  gint waveform;
  gint antialias;
  gint tile;
} RippleValues;

typedef struct
{
  gint run;
} RippleInterface;


/* Declare local functions.
 */
static void    query  (void);
static void    run    (gchar      *name,
		       gint        nparams,
		       GimpParam  *param,
		       gint       *nreturn_vals,
		       GimpParam **return_vals);

static void    ripple              (GimpDrawable *drawable);

static gint    ripple_dialog       (void);
static void    ripple_ok_callback  (GtkWidget    *widget,
				    gpointer      data);

static gdouble displace_amount     (gint      location);
static void    average_two_pixels  (guchar   *dest,
                                    guchar    pixels[4][4],
                                    gdouble   x,
                                    gint      bpp,
                                    gboolean  has_alpha);
static void    average_four_pixels (guchar   *dest,
                                    guchar    pixels[4][4],
                                    gdouble   x,
                                    gint      bpp,
                                    gboolean  has_alpha);

/***** Local vars *****/

GimpPlugInInfo PLUG_IN_INFO =
{
  NULL,  /* init_proc  */
  NULL,  /* quit_proc  */
  query, /* query_proc */
  run,   /* run_proc   */
};

static RippleValues rvals =
{
  20,         /* period      */
  5,          /* amplitude   */
  HORIZONTAL, /* orientation */
  WRAP,       /* edges       */
  SINE,       /* waveform    */
  TRUE,       /* antialias   */
  TRUE        /* tile        */
};

static RippleInterface rpint =
{
  FALSE   /*  run  */
};

/***** Functions *****/

MAIN ()

static void
query (void)
{
  static GimpParamDef args[] =
  {
    { GIMP_PDB_INT32, "run_mode", "Interactive, non-interactive" },
    { GIMP_PDB_IMAGE, "image", "Input image (unused)" },
    { GIMP_PDB_DRAWABLE, "drawable", "Input drawable" },
    { GIMP_PDB_INT32, "period", "period; number of pixels for one wave to complete" },
    { GIMP_PDB_INT32, "amplitude", "amplitude; maximum displacement of wave" },
    { GIMP_PDB_INT32, "orientation", "orientation; 0 = Horizontal, 1 = Vertical" },
    { GIMP_PDB_INT32, "edges", "edges; 0 = smear, 1 =  wrap, 2 = black" },
    { GIMP_PDB_INT32, "waveform", "0 = sawtooth, 1 = sine wave" },
    { GIMP_PDB_INT32, "antialias", "antialias; True or False" },
    { GIMP_PDB_INT32, "tile", "tile; if this is true, the image will retain it's tilability" }
  };

  gimp_install_procedure ("plug_in_ripple",
			  "Ripple the contents of the specified drawable",
			  "Ripples the pixels of the specified drawable. Each row or column will be displaced a certain number of pixels coinciding with the given wave form",
			  "Brian Degenhardt <bdegenha@ucsd.edu>",
			  "Brian Degenhardt",
			  "1997",
			  N_("<Image>/Filters/Distorts/Ripple..."),
			  "RGB*, GRAY*",
			  GIMP_PLUGIN,
			  G_N_ELEMENTS (args), 0,
			  args, NULL);
}

static void
run (gchar      *name,
     gint        nparams,
     GimpParam  *param,
     gint       *nreturn_vals,
     GimpParam **return_vals)
{
  static GimpParam   values[1];
  GimpDrawable      *drawable;
  GimpRunMode        run_mode;
  GimpPDBStatusType  status = GIMP_PDB_SUCCESS;

  run_mode = param[0].data.d_int32;

  /*  Get the specified drawable  */
  drawable = gimp_drawable_get (param[2].data.d_drawable);

  *nreturn_vals = 1;
  *return_vals  = values;

  values[0].type          = GIMP_PDB_STATUS;
  values[0].data.d_status = status;

  switch (run_mode)
    {
    case GIMP_RUN_INTERACTIVE:
      INIT_I18N_UI();
      /*  Possibly retrieve data  */
      gimp_get_data ("plug_in_ripple", &rvals);

      /*  First acquire information with a dialog  */
      if (! ripple_dialog ())
	return;
      break;

    case GIMP_RUN_NONINTERACTIVE:
      INIT_I18N();
      /*  Make sure all the arguments are there!  */
      if (nparams != 10)
	{
	  status = GIMP_PDB_CALLING_ERROR;
	}
      else
	{
	  rvals.period = param[3].data.d_int32;
	  rvals.amplitude = param[4].data.d_int32;
          rvals.orientation = (param[5].data.d_int32) ? VERTICAL : HORIZONTAL;
          rvals.edges = (param[6].data.d_int32);
          rvals.waveform = param[7].data.d_int32;
          rvals.antialias = (param[8].data.d_int32) ? TRUE : FALSE;
          rvals.tile = (param[9].data.d_int32) ? TRUE : FALSE;

	  if (rvals.edges < SMEAR || rvals.edges > BLACK)
	    status = GIMP_PDB_CALLING_ERROR;
	}
      break;

    case GIMP_RUN_WITH_LAST_VALS:
      INIT_I18N();
      /*  Possibly retrieve data  */
      gimp_get_data ("plug_in_ripple", &rvals);
      break;

    default:
      break;
    }

  if (status == GIMP_PDB_SUCCESS)
    {
      /*  Make sure that the drawable is gray or RGB color  */
      if (gimp_drawable_is_rgb (drawable->drawable_id) ||
	  gimp_drawable_is_gray (drawable->drawable_id))
	{
	  gimp_progress_init ( _("Rippling..."));

	  /*  set the tile cache size  */
	  gimp_tile_cache_ntiles (TILE_CACHE_SIZE);

	  /*  run the ripple effect  */
	  ripple (drawable);

	  if (run_mode != GIMP_RUN_NONINTERACTIVE)
	    gimp_displays_flush ();

	  /*  Store data  */
	  if (run_mode == GIMP_RUN_INTERACTIVE)
	    gimp_set_data ("plug_in_ripple", &rvals, sizeof (RippleValues));
	}
      else
	{
	  /* gimp_message ("ripple: cannot operate on indexed color images"); */
	  status = GIMP_PDB_EXECUTION_ERROR;
	}
    }

  values[0].data.d_status = status;

  gimp_drawable_detach (drawable);
}

static void
ripple (GimpDrawable *drawable)
{
  GimpPixelRgn dest_rgn;
  gpointer  pr;
  GimpPixelFetcher *pft;
  gint     width, height;
  gint     bytes;
  gboolean has_alpha;
  guchar  *destline;
  guchar  *dest;
  guchar  *otherdest;
  guchar   pixel[4][4];
  gint     x1, y1, x2, y2;
  gint     x, y;
  gint     progress, max_progress;
  gdouble  needx, needy;

  gint xi, yi;

  pft = gimp_pixel_fetcher_new (drawable);

  gimp_drawable_mask_bounds (drawable->drawable_id, &x1, &y1, &x2, &y2);
  has_alpha = gimp_drawable_has_alpha (drawable->drawable_id);

  width  = drawable->width;
  height = drawable->height;
  bytes  = drawable->bpp;

  if ( rvals.tile )
    {
      rvals.edges = WRAP;
      rvals.period = (width / (width / rvals.period) *
		      (rvals.orientation == HORIZONTAL) +
		      height / (height / rvals.period) *
		      (rvals.orientation == VERTICAL));
    }

  progress     = 0;
  max_progress = (x2 - x1) * (y2 - y1);

  /* Ripple the image.  It's a pretty simple algorithm.  If horizontal
     is selected, then every row is displaced a number of pixels that
     follows the pattern of the waveform selected.  The effect is
     just reproduced with columns if vertical is selected.
  */

  gimp_pixel_rgn_init (&dest_rgn, drawable,
		       x1, y1, (x2 - x1), (y2 - y1), TRUE, TRUE);
  for (pr = gimp_pixel_rgns_register (1, &dest_rgn);
       pr != NULL;
       pr = gimp_pixel_rgns_process (pr))
    {
      if (rvals.orientation == VERTICAL)
	{
          destline = dest_rgn.data;

          for (x = dest_rgn.x; x < (dest_rgn.x + dest_rgn.w); x++)
	    {
              dest = destline;

              for (y = dest_rgn.y; y < dest_rgn.y + dest_rgn.h; y++)
		{
                  otherdest = dest;

                  needy = y + displace_amount(x);
                  yi = floor(needy);

		  /* Tile the image. */
                  if (rvals.edges == WRAP)
		    {
                      needy = fmod(needy + height, height);
                      yi = (yi + height) % height;
		    }
		  /* Smear out the edges of the image by repeating pixels. */
                  else if (rvals.edges == SMEAR)
		    {
		      yi = CLAMP(yi, 0, height - 1);
		    }

                  if (rvals.antialias)
		    {
                      if (yi == height - 1)
			{
			  gimp_pixel_fetcher_get_pixel (pft, x, yi, otherdest);
			  otherdest += bytes;
			}
                      else if (needy < 0 && needy > -1)
			{
			  gimp_pixel_fetcher_get_pixel (pft, x, 0, otherdest);
			  otherdest += bytes;
			}
                      else if (yi == height - 2 || yi == 0)
			{
			  gimp_pixel_fetcher_get_pixel (pft, x, yi, pixel[0]);
			  gimp_pixel_fetcher_get_pixel (pft, x, yi + 1, 
							pixel[1]);

                          average_two_pixels (otherdest, pixel,
                                              needy, bytes, has_alpha);
                          otherdest += bytes;
			}
                      else
			{
			  gimp_pixel_fetcher_get_pixel (pft, x, yi, pixel[0]);
			  gimp_pixel_fetcher_get_pixel (pft, x, yi + 1, 
							pixel[1]);
			  gimp_pixel_fetcher_get_pixel (pft, x, yi - 1, 
							pixel[2]);
			  gimp_pixel_fetcher_get_pixel (pft, x, yi + 2, 
							pixel[3]);

                          average_four_pixels(otherdest, pixel,
                                              needy, bytes, has_alpha);
                          otherdest += bytes;
                      }
		    } /* antialias */
                  else
		    {
		      gimp_pixel_fetcher_get_pixel (pft, x, yi, otherdest);
		    }
                  dest += dest_rgn.rowstride;
		} /* for */

	      destline += bytes;
	    } /* for */

          progress += dest_rgn.w * dest_rgn.h;
          gimp_progress_update ((double) progress / (double) max_progress);
	}
      else /* HORIZONTAL */
	{
          destline = dest_rgn.data;

          for (y = dest_rgn.y; y < (dest_rgn.y + dest_rgn.h); y++)
	    {
              dest = destline;

              for (x = dest_rgn.x; x < (dest_rgn.x + dest_rgn.w); x++)
		{
                  needx = x + displace_amount(y);
                  xi = floor (needx);

		  /* Tile the image. */
                  if (rvals.edges == WRAP)
		    {
                      needx = fmod((needx + width), width);
                      xi = (xi + width) % width;
		    }
		  /* Smear out the edges of the image by repeating pixels. */
                  else if (rvals.edges == SMEAR)
		    {
		      xi = CLAMP(xi, 0, width - 1);
		    }

                  if ( rvals.antialias)
		    {
                      if (xi == width - 1)
			{
			  gimp_pixel_fetcher_get_pixel (pft, xi, y, dest);
			  dest += bytes;
			}
                      else if (floor(needx) ==  -1)
			{
			  gimp_pixel_fetcher_get_pixel (pft, 0, y, dest);
			  dest += bytes;
			}

                      else if (xi == width - 2 || xi == 0)
			{
			  gimp_pixel_fetcher_get_pixel (pft, xi, y, pixel[0]);
			  gimp_pixel_fetcher_get_pixel (pft, xi + 1, y, 
							pixel[1]);

                          average_two_pixels (dest, pixel,
                                              needx, bytes, has_alpha);
                          dest += bytes;
			}
                      else
			{
			  gimp_pixel_fetcher_get_pixel (pft, xi, y, pixel[0]);
			  gimp_pixel_fetcher_get_pixel (pft, xi + 1, y, 
							pixel[1]);
			  gimp_pixel_fetcher_get_pixel (pft, xi - 1, y, 
							pixel[2]);
			  gimp_pixel_fetcher_get_pixel (pft, xi + 2, y, 
							pixel[3]);

                          average_four_pixels(dest, pixel,
                                              needx, bytes, has_alpha);
                          dest += bytes;
			}
		    } /* antialias */

                  else
		    {
		      gimp_pixel_fetcher_get_pixel (pft, xi, y, dest);
		      dest += bytes;
		    }
		} /* for */

              destline += dest_rgn.rowstride;
	    } /* for */

          progress += dest_rgn.w * dest_rgn.h;
          gimp_progress_update ((double) progress / (double) max_progress);
	}
    }  /* for  */

  gimp_pixel_fetcher_destroy (pft);

  /*  update the region  */
  gimp_drawable_flush (drawable);
  gimp_drawable_merge_shadow (drawable->drawable_id, TRUE);
  gimp_drawable_update (drawable->drawable_id, x1, y1, (x2 - x1), (y2 - y1));
}

static gint
ripple_dialog (void)
{
  GtkWidget *dlg;
  GtkWidget *toggle;
  GtkWidget *toggle_vbox;
  GtkWidget *main_vbox;
  GtkWidget *frame;
  GtkWidget *table;
  GtkObject *scale_data;

  gimp_ui_init ("ripple", TRUE);

  dlg = gimp_dialog_new (_("Ripple"), "ripple",
			 gimp_standard_help_func, "filters/ripple.html",
			 GTK_WIN_POS_MOUSE,
			 FALSE, TRUE, FALSE,

			 GTK_STOCK_CANCEL, gtk_widget_destroy,
			 NULL, 1, NULL, FALSE, TRUE,
			 GTK_STOCK_OK, ripple_ok_callback,
			 NULL, NULL, NULL, TRUE, FALSE,

			 NULL);

  g_signal_connect (dlg, "destroy",
                    G_CALLBACK (gtk_main_quit),
                    NULL);

  /*  The main vbox  */
  main_vbox = gtk_vbox_new (FALSE, 6);
  gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 6);
  gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dlg)->vbox), main_vbox,
		      FALSE, FALSE, 0);

  /* The table to hold the four frames of options */
  table = gtk_table_new (2, 2, FALSE);
  gtk_table_set_col_spacings (GTK_TABLE (table), 6);
  gtk_table_set_row_spacings (GTK_TABLE (table), 6);
  gtk_box_pack_start (GTK_BOX (main_vbox), table, FALSE, FALSE, 0);

  /*  Options section  */
  frame = gtk_frame_new ( _("Options"));
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_table_attach (GTK_TABLE (table), frame, 0, 1, 0, 1,
		    GTK_EXPAND | GTK_FILL, GTK_EXPAND | GTK_FILL, 0, 0);

  toggle_vbox = gtk_vbox_new (FALSE, 1);
  gtk_container_set_border_width (GTK_CONTAINER (toggle_vbox), 2);
  gtk_container_add (GTK_CONTAINER (frame), toggle_vbox);

  toggle = gtk_check_button_new_with_mnemonic (_("_Antialiasing"));
  gtk_box_pack_start (GTK_BOX (toggle_vbox), toggle, FALSE, FALSE, 0);
  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), rvals.antialias);
  gtk_widget_show (toggle);

  g_signal_connect (toggle, "toggled",
                    G_CALLBACK (gimp_toggle_button_update),
                    &rvals.antialias);

  toggle = gtk_check_button_new_with_mnemonic ( _("_Retain Tilability"));
  gtk_box_pack_start (GTK_BOX (toggle_vbox), toggle, FALSE, FALSE, 0);
  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), (rvals.tile));
  gtk_widget_show (toggle);

  g_signal_connect (toggle, "toggled",
                    G_CALLBACK (gimp_toggle_button_update),
                    &rvals.tile);

  gtk_widget_show (toggle_vbox);
  gtk_widget_show (frame);

  /*  Orientation toggle box  */
  frame = gimp_radio_group_new2 (TRUE, _("Orientation"),
                                 G_CALLBACK (gimp_radio_button_update),
                                 &rvals.orientation,
                                 GINT_TO_POINTER (rvals.orientation),

                                 _("_Horizontal"),
                                 GINT_TO_POINTER (HORIZONTAL), NULL,

                                 _("_Vertical"),
                                 GINT_TO_POINTER (VERTICAL), NULL,

                                 NULL);

  gtk_table_attach (GTK_TABLE (table), frame, 1, 2, 0, 1,
		    GTK_EXPAND | GTK_FILL, GTK_EXPAND | GTK_FILL, 0, 0);
  gtk_widget_show (frame);

  /*  Edges toggle box  */
  frame = gimp_radio_group_new2 (TRUE, _("Edges"),
				 G_CALLBACK (gimp_radio_button_update),
				 &rvals.edges, (gpointer) rvals.edges,

				 _("_Wrap"),  (gpointer) WRAP, NULL,
				 _("_Smear"), (gpointer) SMEAR, NULL,
				 _("_Black"), (gpointer) BLACK, NULL,

				 NULL);
  gtk_table_attach (GTK_TABLE (table), frame, 0, 1, 1, 2,
		    GTK_FILL | GTK_EXPAND, GTK_FILL | GTK_EXPAND, 0, 0);
  gtk_widget_show (frame);

  /*  Wave toggle box  */
  frame = gimp_radio_group_new2 (TRUE, _("Wave Type"),
				 G_CALLBACK (gimp_radio_button_update),
				 &rvals.waveform, (gpointer) rvals.waveform,

				 _("Saw_tooth"), (gpointer) SAWTOOTH, NULL,
				 _("S_ine"),     (gpointer) SINE, NULL,

				 NULL);
  gtk_table_attach (GTK_TABLE (table), frame, 1, 2, 1, 2,
		    GTK_FILL | GTK_EXPAND, GTK_FILL | GTK_EXPAND, 0, 0);
  gtk_widget_show (frame);

  gtk_widget_show (table);

  /*  Parameter Settings  */
  frame = gtk_frame_new ( _("Parameter Settings"));
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);

  table = gtk_table_new (2, 3, FALSE);
  gtk_table_set_col_spacings (GTK_TABLE (table), 4);
  gtk_table_set_row_spacings (GTK_TABLE (table), 2);
  gtk_container_set_border_width (GTK_CONTAINER (table), 4);
  gtk_container_add (GTK_CONTAINER (frame), table);

  /*  Period  */
  scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 0,
				     _("_Period:"), SCALE_WIDTH, 0,
				     rvals.period, 0, 200, 1, 10, 0,
				     TRUE, 0, 0,
				     NULL, NULL);
  g_signal_connect (scale_data, "value_changed",
                    G_CALLBACK (gimp_int_adjustment_update),
                    &rvals.period);

  /*  Amplitude  */
  scale_data = gimp_scale_entry_new (GTK_TABLE (table), 0, 1,
				     _("A_mplitude:"), SCALE_WIDTH, 0,
				     rvals.amplitude, 0, 200, 1, 10, 0,
				     TRUE, 0, 0,
				     NULL, NULL);
  g_signal_connect (scale_data, "value_changed",
                    G_CALLBACK (gimp_int_adjustment_update),
                    &rvals.amplitude);

  gtk_widget_show (frame);
  gtk_widget_show (table);

  gtk_widget_show (main_vbox);
  gtk_widget_show (dlg);

  gtk_main ();
  gdk_flush ();

  return rpint.run;
}

/*  Ripple interface functions  */

static void
ripple_ok_callback (GtkWidget *widget,
		    gpointer   data)
{
  rpint.run = TRUE;

  gtk_widget_destroy (GTK_WIDGET (data));
}

static void
average_two_pixels (guchar   *dest,
                    guchar    pixels[4][4],
                    gdouble   x,
                    gint      bpp,
                    gboolean  has_alpha)
{
  gint b;

  x = fmod (x, 1.0);
  if (has_alpha)
    {
      double xa0 = pixels[0][bpp-1] * (1.0 - x);
      double xa1 = pixels[1][bpp-1] * x;
      double alpha;

      alpha = xa0 + xa1;
      dest[bpp-1] = alpha;
      if (dest[bpp-1])
          for (b = 0; b < bpp-1; b++)
              dest[b] = (xa0 * pixels[0][b] + xa1 * pixels[1][b])/alpha;
    }
  else
    {
      for (b = 0; b < bpp; b++)
          dest[b] = (1.0 - x) * pixels[0][b] + x * pixels[1][b];
    }
}

static void
average_four_pixels (guchar   *dest,
                     guchar    pixels[4][4],
                     gdouble   x,
                     gint      bpp,
                     gboolean  has_alpha)
{
  gint b;

  x = fmod (x, 1.0);
  if (has_alpha)
    {
      double xa0 = pixels[0][bpp-1] * (1.0 - x)/2;
      double xa1 = pixels[1][bpp-1] * x/2;
      double xa2 = pixels[2][bpp-1] * (1.0 - x)/2;
      double xa3 = pixels[3][bpp-1] * x/2;
      double alpha;

      alpha = xa0 + xa1 + xa2 + xa3;
      dest[bpp-1] = alpha;
      if (dest[bpp-1])
          for (b = 0; b < bpp-1; b++)
              dest[b] = (xa0 * pixels[0][b] + xa1 * pixels[1][b]
                         + xa2 * pixels[2][b] + xa3 * pixels[3][b])/alpha;
    }
  else
    {
      for (b = 0; b < bpp; b++)
          dest[b] = (1.0 - x) * (pixels[0][b] + pixels[2][b])
                    + x * (pixels[1][b] + pixels[3][b]);
    }
}

static gdouble
displace_amount (gint location)
{
  switch (rvals.waveform)
    {
    case SINE:
      return (rvals.amplitude *
              sin (location * (2 * G_PI) / (gdouble) rvals.period));
    case SAWTOOTH:
      return floor (rvals.amplitude *
		    (fabs ((((location % rvals.period) /
			     (gdouble) rvals.period) * 4) - 2) - 1));
    }

  return 0.0;
}