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-rw-r--r--plug-ins/common/edge-dog.c1029
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diff --git a/plug-ins/common/edge-dog.c b/plug-ins/common/edge-dog.c
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+/* GIMP - The GNU 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Gimp plug-in dog.c: (C) 2004 William Skaggs
+ *
+ * Edge detection using the "Difference of Gaussians" method.
+ * Finds edges by doing two Gaussian blurs with different radius, and
+ * subtracting the results. Blurring is done using code taken from
+ * gauss_rle.c (as of Gimp 2.1, incorporated into gauss.c).
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include <libgimp/gimp.h>
+#include <libgimp/gimpui.h>
+
+#include "libgimp/stdplugins-intl.h"
+
+
+#define PLUG_IN_PROC "plug-in-dog"
+#define PLUG_IN_BINARY "edge-dog"
+#define PLUG_IN_ROLE "gimp-edge-dog"
+
+
+typedef struct
+{
+ gdouble inner;
+ gdouble outer;
+ gboolean normalize;
+ gboolean invert;
+} DoGValues;
+
+
+/* Declare local functions.
+ */
+static void query (void);
+static void run (const gchar *name,
+ gint nparams,
+ const GimpParam *param,
+ gint *nreturn_vals,
+ GimpParam **return_vals);
+
+static gint dog_dialog (gint32 image_ID,
+ GimpDrawable *drawable);
+
+static void gauss_rle (GimpDrawable *drawable,
+ gdouble radius,
+ gint pass,
+ gboolean show_progress);
+
+static void compute_difference (GimpDrawable *drawable,
+ GimpDrawable *drawable1,
+ GimpDrawable *drawable2,
+ guchar *maxval);
+
+static void normalize_invert (GimpDrawable *drawable,
+ gboolean normalize,
+ guint maxval,
+ gboolean invert);
+
+static void dog (gint32 image_ID,
+ GimpDrawable *drawable,
+ gdouble inner,
+ gdouble outer,
+ gboolean show_progress);
+
+static void preview_update_preview (GimpPreview *preview,
+ GimpDrawable *drawable);
+static void change_radius_callback (GtkWidget *widget,
+ gpointer data);
+
+
+
+/*
+ * Gaussian blur helper functions
+ */
+static gint * make_curve (gdouble sigma,
+ gint *length);
+static void run_length_encode (guchar *src,
+ gint *dest,
+ gint bytes,
+ gint width);
+
+
+const GimpPlugInInfo PLUG_IN_INFO =
+{
+ NULL, /* init_proc */
+ NULL, /* quit_proc */
+ query, /* query_proc */
+ run, /* run_proc */
+};
+
+static DoGValues dogvals =
+{
+ 3.0, /* inner radius */
+ 1.0, /* outer radius */
+ TRUE, /* normalize */
+ TRUE /* invert */
+};
+
+MAIN ()
+
+static void
+query (void)
+{
+ static const GimpParamDef args[] =
+ {
+ { GIMP_PDB_INT32, "run-mode", "The run mode { RUN-INTERACTIVE (0), RUN-NONINTERACTIVE (1) }" },
+ { GIMP_PDB_IMAGE, "image", "Input image" },
+ { GIMP_PDB_DRAWABLE, "drawable", "Input drawable" },
+ { GIMP_PDB_FLOAT, "inner", "Radius of inner gaussian blur (in pixels, > 0.0)" },
+ { GIMP_PDB_FLOAT, "outer", "Radius of outer gaussian blur (in pixels, > 0.0)" },
+ { GIMP_PDB_INT32, "normalize", "Normalize { TRUE, FALSE }" },
+ { GIMP_PDB_INT32, "invert", "Invert { TRUE, FALSE }" }
+ };
+
+ gimp_install_procedure (PLUG_IN_PROC,
+ N_("Edge detection with control of edge thickness"),
+ "Applies two Gaussian blurs to the drawable, and "
+ "subtracts the results. This is robust and widely "
+ "used method for detecting edges.",
+ "Spencer Kimball, Peter Mattis, Sven Neumann, William Skaggs",
+ "Spencer Kimball, Peter Mattis, Sven Neumann, William Skaggs",
+ "1995-2004",
+ N_("_Difference of Gaussians (legacy)..."),
+ "RGB*, GRAY*",
+ GIMP_PLUGIN,
+ G_N_ELEMENTS (args), 0,
+ args, NULL);
+
+ gimp_plugin_menu_register (PLUG_IN_PROC, "<Image>/Filters/Edge-Detect");
+}
+
+static void
+run (const gchar *name,
+ gint nparams,
+ const GimpParam *param,
+ gint *nreturn_vals,
+ GimpParam **return_vals)
+{
+ static GimpParam values[2];
+ gint32 image_ID;
+ GimpDrawable *drawable;
+ GimpRunMode run_mode;
+ GimpPDBStatusType status = GIMP_PDB_SUCCESS;
+ GError *error = NULL;
+
+ run_mode = param[0].data.d_int32;
+
+ INIT_I18N ();
+
+ *nreturn_vals = 1;
+ *return_vals = values;
+
+ values[0].type = GIMP_PDB_STATUS;
+ values[0].data.d_status = status;
+
+ if (! gimp_item_is_layer (param[2].data.d_drawable))
+ {
+ g_set_error (&error, 0, 0, "%s",
+ _("Can operate on layers only "
+ "(but was called on channel or mask)."));
+ status = GIMP_PDB_EXECUTION_ERROR;
+ }
+
+ if (status == GIMP_PDB_SUCCESS)
+ {
+ /* Get the specified image and drawable */
+ image_ID = param[1].data.d_image;
+ drawable = gimp_drawable_get (param[2].data.d_drawable);
+
+ /* set the tile cache size so that the gaussian blur works well */
+ gimp_tile_cache_ntiles (2 *
+ (MAX (drawable->width, drawable->height) /
+ gimp_tile_width () + 1));
+
+ if (strcmp (name, PLUG_IN_PROC) == 0)
+ {
+ switch (run_mode)
+ {
+ case GIMP_RUN_INTERACTIVE:
+ /* Possibly retrieve data */
+ gimp_get_data (PLUG_IN_PROC, &dogvals);
+
+ /* First acquire information with a dialog */
+ if (! dog_dialog (image_ID, drawable))
+ return;
+ break;
+
+ case GIMP_RUN_NONINTERACTIVE:
+ /* Make sure all the arguments are there! */
+ if (nparams != 7)
+ status = GIMP_PDB_CALLING_ERROR;
+
+ if (status == GIMP_PDB_SUCCESS)
+ {
+ dogvals.inner = param[3].data.d_float;
+ dogvals.outer = param[4].data.d_float;
+ dogvals.normalize = param[5].data.d_int32;
+ dogvals.invert = param[6].data.d_int32;
+
+ if (dogvals.inner <= 0.0 || dogvals.outer <= 0.0)
+ status = GIMP_PDB_CALLING_ERROR;
+ }
+ break;
+
+ case GIMP_RUN_WITH_LAST_VALS:
+ /* Possibly retrieve data */
+ gimp_get_data (PLUG_IN_PROC, &dogvals);
+ break;
+
+ default:
+ break;
+ }
+ }
+ else
+ {
+ status = GIMP_PDB_CALLING_ERROR;
+ }
+ }
+
+ 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 (_("DoG Edge Detect"));
+
+ /* run the Difference of Gaussians */
+ gimp_image_undo_group_start (image_ID);
+
+ dog (image_ID, drawable, dogvals.inner, dogvals.outer, TRUE);
+
+ gimp_image_undo_group_end (image_ID);
+
+ gimp_progress_update (1.0);
+
+ /* Store data */
+ if (run_mode == GIMP_RUN_INTERACTIVE)
+ gimp_set_data (PLUG_IN_PROC, &dogvals, sizeof (DoGValues));
+
+ if (run_mode != GIMP_RUN_NONINTERACTIVE)
+ gimp_displays_flush ();
+ }
+ else
+ {
+ status = GIMP_PDB_EXECUTION_ERROR;
+ *nreturn_vals = 2;
+
+ values[1].type = GIMP_PDB_STRING;
+ values[1].data.d_string = _("Cannot operate on indexed color images.");
+ }
+
+ gimp_drawable_detach (drawable);
+ }
+
+ if (status != GIMP_PDB_SUCCESS && error)
+ {
+ *nreturn_vals = 2;
+ values[1].type = GIMP_PDB_STRING;
+ values[1].data.d_string = error->message;
+ }
+
+ values[0].data.d_status = status;
+}
+
+static gint
+dog_dialog (gint32 image_ID,
+ GimpDrawable *drawable)
+{
+ GtkWidget *dialog;
+ GtkWidget *frame;
+ GtkWidget *button;
+ GtkWidget *main_vbox;
+ GtkWidget *preview;
+ GtkWidget *coord;
+ GimpUnit unit;
+ gdouble xres;
+ gdouble yres;
+ gboolean run;
+
+ gimp_ui_init (PLUG_IN_BINARY, FALSE);
+
+ dialog = gimp_dialog_new (_("DoG Edge Detect"), PLUG_IN_ROLE,
+ NULL, 0,
+ gimp_standard_help_func, PLUG_IN_PROC,
+
+ _("_Cancel"), GTK_RESPONSE_CANCEL,
+ _("_OK"), GTK_RESPONSE_OK,
+
+ NULL);
+
+ gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
+ GTK_RESPONSE_OK,
+ GTK_RESPONSE_CANCEL,
+ -1);
+
+ gimp_window_set_transient (GTK_WINDOW (dialog));
+
+ main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
+ gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
+ gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
+ main_vbox, TRUE, TRUE, 0);
+ gtk_widget_show (main_vbox);
+
+ preview = gimp_drawable_preview_new_from_drawable_id (drawable->drawable_id);
+ gtk_box_pack_start (GTK_BOX (main_vbox), preview, FALSE, FALSE, 0);
+ gtk_widget_show (preview);
+
+ g_signal_connect (preview, "invalidated",
+ G_CALLBACK (preview_update_preview),
+ drawable);
+
+ frame = gimp_frame_new (_("Smoothing Parameters"));
+ gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
+ gtk_widget_show (frame);
+
+ /* Get the image resolution and unit */
+ gimp_image_get_resolution (image_ID, &xres, &yres);
+ unit = gimp_image_get_unit (image_ID);
+
+ coord = gimp_coordinates_new (unit, "%a", TRUE, FALSE, -1,
+ GIMP_SIZE_ENTRY_UPDATE_SIZE,
+
+ FALSE,
+ TRUE,
+
+ _("_Radius 1:"), dogvals.inner, xres,
+ 0, 8 * MAX (drawable->width, drawable->height),
+ 0, 0,
+
+ _("R_adius 2:"), dogvals.outer, yres,
+ 0, 8 * MAX (drawable->width, drawable->height),
+ 0, 0);
+
+ gtk_container_add (GTK_CONTAINER (frame), coord);
+ gtk_widget_show (coord);
+
+ gimp_size_entry_set_pixel_digits (GIMP_SIZE_ENTRY (coord), 1);
+ g_signal_connect (coord, "value-changed",
+ G_CALLBACK (change_radius_callback),
+ preview);
+
+ button = gtk_check_button_new_with_mnemonic (_("_Normalize"));
+ gtk_box_pack_start (GTK_BOX (main_vbox), button, FALSE, FALSE, 0);
+ gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button), dogvals.normalize);
+ g_signal_connect (button, "toggled",
+ G_CALLBACK (gimp_toggle_button_update),
+ &dogvals.normalize);
+ g_signal_connect_swapped (button, "toggled",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+ gtk_widget_show (button);
+
+ button = gtk_check_button_new_with_mnemonic (_("_Invert"));
+ gtk_box_pack_start (GTK_BOX (main_vbox), button, FALSE, FALSE, 0);
+ gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button), dogvals.invert);
+ g_signal_connect (button, "toggled",
+ G_CALLBACK (gimp_toggle_button_update),
+ &dogvals.invert);
+ g_signal_connect_swapped (button, "toggled",
+ G_CALLBACK (gimp_preview_invalidate),
+ preview);
+ gtk_widget_show (button);
+
+ gtk_widget_show (dialog);
+
+ run = (gimp_dialog_run (GIMP_DIALOG (dialog)) == GTK_RESPONSE_OK);
+
+ if (run)
+ {
+ dogvals.inner = gimp_size_entry_get_refval (GIMP_SIZE_ENTRY (coord), 0);
+ dogvals.outer = gimp_size_entry_get_refval (GIMP_SIZE_ENTRY (coord), 1);
+ }
+
+ gtk_widget_destroy (dialog);
+
+
+ return run;
+}
+
+
+/* Convert from separated to premultiplied alpha, on a single scan line. */
+static void
+multiply_alpha (guchar *buf,
+ gint width,
+ gint bytes)
+{
+ gint i, j;
+ gdouble alpha;
+
+ for (i = 0; i < width * bytes; i += bytes)
+ {
+ alpha = buf[i + bytes - 1] * (1.0 / 255.0);
+
+ for (j = 0; j < bytes - 1; j++)
+ buf[i + j] *= alpha;
+ }
+}
+
+/* Convert from premultiplied to separated alpha, on a single scan
+ line. */
+static void
+separate_alpha (guchar *buf,
+ gint width,
+ gint bytes)
+{
+ gint i, j;
+ guchar alpha;
+ gdouble recip_alpha;
+ gint new_val;
+
+ for (i = 0; i < width * bytes; i += bytes)
+ {
+ alpha = buf[i + bytes - 1];
+
+ if (alpha != 0 && alpha != 255)
+ {
+ recip_alpha = 255.0 / alpha;
+
+ for (j = 0; j < bytes - 1; j++)
+ {
+ new_val = buf[i + j] * recip_alpha;
+ buf[i + j] = MIN (255, new_val);
+ }
+ }
+ }
+}
+
+static void
+dog (gint32 image_ID,
+ GimpDrawable *drawable,
+ gdouble inner,
+ gdouble outer,
+ gboolean show_progress)
+{
+ GimpDrawable *drawable1;
+ GimpDrawable *drawable2;
+ gint32 drawable_id = drawable->drawable_id;
+ gint32 layer1;
+ gint32 layer2;
+ gint width, height;
+ gint x1, y1;
+ guchar maxval = 255;
+
+ if (! gimp_drawable_mask_intersect (drawable_id, &x1, &y1, &width, &height))
+ return;
+
+ gimp_drawable_flush (drawable);
+
+ layer1 = gimp_layer_copy (drawable_id);
+ gimp_item_set_visible (layer1, FALSE);
+ gimp_item_set_name (layer1, "dog_scratch_layer1");
+ gimp_image_insert_layer (image_ID, layer1,
+ gimp_item_get_parent (drawable_id), 0);
+
+ layer2 = gimp_layer_copy (drawable_id);
+ gimp_item_set_visible (layer2, FALSE);
+ gimp_item_set_name (layer2, "dog_scratch_layer2");
+ gimp_image_insert_layer (image_ID, layer2,
+ gimp_item_get_parent (drawable_id), 0);
+
+ drawable1 = gimp_drawable_get (layer1);
+ drawable2 = gimp_drawable_get (layer2);
+
+ gauss_rle (drawable1, inner, 0, show_progress);
+ gauss_rle (drawable2, outer, 1, show_progress);
+
+ compute_difference (drawable, drawable1, drawable2, &maxval);
+
+ gimp_drawable_detach (drawable1);
+ gimp_drawable_detach (drawable2);
+
+ gimp_image_remove_layer (image_ID, layer1);
+ gimp_image_remove_layer (image_ID, layer2);
+
+ gimp_drawable_flush (drawable);
+ gimp_drawable_merge_shadow (drawable_id, TRUE);
+ gimp_drawable_update (drawable_id, x1, y1, width, height);
+
+ if (dogvals.normalize || dogvals.invert)
+ /* gimp_invert doesn't work properly with previews due to shadow handling
+ * so reimplement it here - see Bug 557380
+ */
+ {
+ normalize_invert (drawable, dogvals.normalize, maxval, dogvals.invert);
+ gimp_drawable_flush (drawable);
+ gimp_drawable_merge_shadow (drawable_id, TRUE);
+ gimp_drawable_update (drawable_id, x1, y1, width, height);
+ }
+}
+
+
+static void
+compute_difference (GimpDrawable *drawable,
+ GimpDrawable *drawable1,
+ GimpDrawable *drawable2,
+ guchar *maxval)
+{
+ GimpPixelRgn src1_rgn, src2_rgn, dest_rgn;
+ gint width, height;
+ gint bpp;
+ gpointer pr;
+ gint x, y, k;
+ gint x1, y1;
+ gboolean has_alpha;
+
+ *maxval = 0;
+
+ if (! gimp_drawable_mask_intersect (drawable->drawable_id,
+ &x1, &y1, &width, &height))
+ return;
+
+ bpp = drawable->bpp;
+ has_alpha = gimp_drawable_has_alpha (drawable->drawable_id);
+
+ gimp_pixel_rgn_init (&src1_rgn,
+ drawable1, 0, 0, drawable1->width, drawable1->height,
+ FALSE, FALSE);
+ gimp_pixel_rgn_init (&src2_rgn,
+ drawable2, 0, 0, drawable1->width, drawable1->height,
+ FALSE, FALSE);
+ gimp_pixel_rgn_init (&dest_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ TRUE, TRUE);
+
+ for (pr = gimp_pixel_rgns_register (3, &src1_rgn, &src2_rgn, &dest_rgn);
+ pr != NULL;
+ pr = gimp_pixel_rgns_process (pr))
+ {
+ guchar *src1 = src1_rgn.data;
+ guchar *src2 = src2_rgn.data;
+ guchar *dest = dest_rgn.data;
+ gint row = src1_rgn.y - y1;
+
+ for (y = 0; y < src1_rgn.h; y++, row++)
+ {
+ guchar *s1 = src1;
+ guchar *s2 = src2;
+ guchar *d = dest;
+ gint col = src1_rgn.x - x1;
+
+ for (x = 0; x < src1_rgn.w; x++, col++)
+ {
+
+ if (has_alpha)
+ {
+ for (k = 0; k < bpp-1; k++)
+ {
+ d[k] = CLAMP0255 (s1[k] - s2[k]);
+ *maxval = MAX (d[k], *maxval);
+ }
+ }
+ else
+ {
+ for (k = 0; k < bpp; k++)
+ {
+ d[k] = CLAMP0255 (s1[k] - s2[k]);
+ *maxval = MAX (d[k], *maxval);
+ }
+ }
+
+ s1 += bpp;
+ s2 += bpp;
+ d += bpp;
+ }
+
+ src1 += src1_rgn.rowstride;
+ src2 += src2_rgn.rowstride;
+ dest += dest_rgn.rowstride;
+ }
+ }
+}
+
+
+static void
+normalize_invert (GimpDrawable *drawable,
+ gboolean normalize,
+ guint maxval,
+ gboolean invert)
+{
+ GimpPixelRgn src_rgn, dest_rgn;
+ gint bpp;
+ gpointer pr;
+ gint x, y, k;
+ gint x1, y1;
+ gint width, height;
+ gboolean has_alpha;
+ gdouble factor;
+
+ if (normalize && maxval != 0) {
+ factor = 255.0 / maxval;
+ }
+ else
+ factor = 1.0;
+
+ if (! gimp_drawable_mask_intersect (drawable->drawable_id,
+ &x1, &y1, &width, &height))
+ return;
+
+ bpp = drawable->bpp;
+ has_alpha = gimp_drawable_has_alpha(drawable->drawable_id);
+
+ gimp_pixel_rgn_init (&src_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ FALSE, FALSE);
+ gimp_pixel_rgn_init (&dest_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ TRUE, TRUE);
+
+ for (pr = gimp_pixel_rgns_register (2, &src_rgn, &dest_rgn);
+ pr != NULL;
+ pr = gimp_pixel_rgns_process (pr))
+ {
+ guchar *src = src_rgn.data;
+ guchar *dest = dest_rgn.data;
+ gint row = src_rgn.y - y1;
+
+ for (y = 0; y < src_rgn.h; y++, row++)
+ {
+ guchar *s = src;
+ guchar *d = dest;
+ gint col = src_rgn.x - x1;
+
+ for (x = 0; x < src_rgn.w; x++, col++)
+ {
+
+ if (has_alpha)
+ {
+ for (k = 0; k < bpp-1; k++)
+ {
+ d[k] = factor * s[k];
+ if (invert)
+ d[k] = 255 - d[k];
+ }
+ }
+ else
+ {
+ for (k = 0; k < bpp; k++)
+ {
+ d[k] = factor * s[k];
+ if (invert)
+ d[k] = 255 - d[k];
+ }
+ }
+
+ s += bpp;
+ d += bpp;
+ }
+
+ src += src_rgn.rowstride;
+ dest += dest_rgn.rowstride;
+ }
+ }
+}
+
+
+static void
+gauss_rle (GimpDrawable *drawable,
+ gdouble radius,
+ gint pass,
+ gboolean show_progress)
+{
+ GimpPixelRgn src_rgn, dest_rgn;
+ gint width, height;
+ gint bytes;
+ gint has_alpha;
+ guchar *dest, *dp;
+ guchar *src, *sp;
+ gint *buf, *bb;
+ gint pixels;
+ gint total = 1;
+ gint x1, y1;
+ gint i, row, col, b;
+ gint start, end;
+ gdouble progress, max_progress;
+ gint *curve;
+ gint *sum = NULL;
+ gint val;
+ gint length;
+ gint initial_p, initial_m;
+ gdouble std_dev;
+
+ if (radius <= 0.0)
+ return;
+
+ if (! gimp_drawable_mask_intersect (drawable->drawable_id,
+ &x1, &y1, &width, &height))
+ return;
+
+ bytes = drawable->bpp;
+ has_alpha = gimp_drawable_has_alpha(drawable->drawable_id);
+
+ buf = g_new (gint, MAX (width, height) * 2);
+
+ /* allocate buffers for source and destination pixels */
+ src = g_new (guchar, MAX (width, height) * bytes);
+ dest = g_new (guchar, MAX (width, height) * bytes);
+
+ gimp_pixel_rgn_init (&src_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ FALSE, FALSE);
+ gimp_pixel_rgn_init (&dest_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ TRUE, TRUE);
+
+ progress = 0.0;
+ max_progress = 2 * width * height;
+
+ /* First the vertical pass */
+ radius = fabs (radius) + 1.0;
+ std_dev = sqrt (-(radius * radius) / (2 * log (1.0 / 255.0)));
+
+ curve = make_curve (std_dev, &length);
+ sum = g_new (gint, 2 * length + 1);
+
+ sum[0] = 0;
+
+ for (i = 1; i <= length*2; i++)
+ sum[i] = curve[i-length-1] + sum[i-1];
+ sum += length;
+
+ total = sum[length] - sum[-length];
+
+ for (col = 0; col < width; col++)
+ {
+ gimp_pixel_rgn_get_col (&src_rgn, src, col + x1, y1, height);
+
+ if (has_alpha)
+ multiply_alpha (src, height, bytes);
+
+ sp = src;
+ dp = dest;
+
+ for (b = 0; b < bytes; b++)
+ {
+ initial_p = sp[b];
+ initial_m = sp[(height-1) * bytes + b];
+
+ /* Determine a run-length encoded version of the row */
+ run_length_encode (sp + b, buf, bytes, height);
+
+ for (row = 0; row < height; row++)
+ {
+ start = (row < length) ? -row : -length;
+ end = (height <= (row + length) ?
+ (height - row - 1) : length);
+
+ val = 0;
+ i = start;
+ bb = buf + (row + i) * 2;
+
+ if (start != -length)
+ val += initial_p * (sum[start] - sum[-length]);
+
+ while (i < end)
+ {
+ pixels = bb[0];
+ i += pixels;
+
+ if (i > end)
+ i = end;
+
+ val += bb[1] * (sum[i] - sum[start]);
+ bb += (pixels * 2);
+ start = i;
+ }
+
+ if (end != length)
+ val += initial_m * (sum[length] - sum[end]);
+
+ dp[row * bytes + b] = val / total;
+ }
+ }
+
+ if (has_alpha)
+ separate_alpha (dest, height, bytes);
+
+ gimp_pixel_rgn_set_col (&dest_rgn, dest, col + x1, y1, height);
+
+ if (show_progress)
+ {
+ progress += height;
+
+ if ((col % 32) == 0)
+ gimp_progress_update (0.5 * (pass + (progress / max_progress)));
+ }
+ }
+
+ /* prepare for the horizontal pass */
+ gimp_pixel_rgn_init (&src_rgn,
+ drawable, 0, 0, drawable->width, drawable->height,
+ FALSE, TRUE);
+
+ /* Now the horizontal pass */
+ for (row = 0; row < height; row++)
+ {
+ gimp_pixel_rgn_get_row (&src_rgn, src, x1, row + y1, width);
+ if (has_alpha)
+ multiply_alpha (src, width, bytes);
+
+ sp = src;
+ dp = dest;
+
+ for (b = 0; b < bytes; b++)
+ {
+ initial_p = sp[b];
+ initial_m = sp[(width-1) * bytes + b];
+
+ /* Determine a run-length encoded version of the row */
+ run_length_encode (sp + b, buf, bytes, width);
+
+ for (col = 0; col < width; col++)
+ {
+ start = (col < length) ? -col : -length;
+ end = (width <= (col + length)) ? (width - col - 1) : length;
+
+ val = 0;
+ i = start;
+ bb = buf + (col + i) * 2;
+
+ if (start != -length)
+ val += initial_p * (sum[start] - sum[-length]);
+
+ while (i < end)
+ {
+ pixels = bb[0];
+ i += pixels;
+
+ if (i > end)
+ i = end;
+
+ val += bb[1] * (sum[i] - sum[start]);
+ bb += (pixels * 2);
+ start = i;
+ }
+
+ if (end != length)
+ val += initial_m * (sum[length] - sum[end]);
+
+ dp[col * bytes + b] = val / total;
+ }
+ }
+
+ if (has_alpha)
+ separate_alpha (dest, width, bytes);
+
+ gimp_pixel_rgn_set_row (&dest_rgn, dest, x1, row + y1, width);
+
+ if (show_progress)
+ {
+ progress += width;
+
+ if ((row % 32) == 0)
+ gimp_progress_update (0.5 * (pass + (progress / max_progress)));
+ }
+ }
+
+ /* merge the shadow, update the drawable */
+ gimp_drawable_flush (drawable);
+ gimp_drawable_merge_shadow (drawable->drawable_id, TRUE);
+ gimp_drawable_update (drawable->drawable_id, x1, y1, width, height);
+
+ /* free buffers */
+ g_free (buf);
+ g_free (src);
+ g_free (dest);
+}
+
+/*
+ * The equations: g(r) = exp (- r^2 / (2 * sigma^2))
+ * r = sqrt (x^2 + y ^2)
+ */
+
+static gint *
+make_curve (gdouble sigma,
+ gint *length)
+{
+ gint *curve;
+ gdouble sigma2;
+ gdouble l;
+ gint temp;
+ gint i, n;
+
+ sigma2 = 2 * sigma * sigma;
+ l = sqrt (-sigma2 * log (1.0 / 255.0));
+
+ n = ceil (l) * 2;
+ if ((n % 2) == 0)
+ n += 1;
+
+ curve = g_new (gint, n);
+
+ *length = n / 2;
+ curve += *length;
+ curve[0] = 255;
+
+ for (i = 1; i <= *length; i++)
+ {
+ temp = (gint) (exp (- (i * i) / sigma2) * 255);
+ curve[-i] = temp;
+ curve[i] = temp;
+ }
+
+ return curve;
+}
+
+static void
+run_length_encode (guchar *src,
+ gint *dest,
+ gint bytes,
+ gint width)
+{
+ gint start;
+ gint i;
+ gint j;
+ guchar last;
+
+ last = *src;
+ src += bytes;
+ start = 0;
+
+ for (i = 1; i < width; i++)
+ {
+ if (*src != last)
+ {
+ for (j = start; j < i; j++)
+ {
+ *dest++ = (i - j);
+ *dest++ = last;
+ }
+ start = i;
+ last = *src;
+ }
+ src += bytes;
+ }
+
+ for (j = start; j < i; j++)
+ {
+ *dest++ = (i - j);
+ *dest++ = last;
+ }
+}
+
+static void
+preview_update_preview (GimpPreview *preview,
+ GimpDrawable *drawable)
+{
+ gint x1, y1;
+ gint width, height;
+ gint bpp;
+ guchar *buffer;
+ GimpPixelRgn src_rgn;
+ GimpPixelRgn preview_rgn;
+ gint32 image_id, src_image_id;
+ gint32 preview_id;
+ GimpDrawable *preview_drawable;
+
+ bpp = gimp_drawable_bpp (drawable->drawable_id);
+
+ gimp_preview_get_position (preview, &x1, &y1);
+ gimp_preview_get_size (preview, &width, &height);
+
+ buffer = g_new (guchar, width * height * bpp);
+
+ gimp_pixel_rgn_init (&src_rgn, drawable,
+ x1, y1, width, height, FALSE, FALSE);
+ gimp_pixel_rgn_get_rect (&src_rgn, buffer,
+ x1, y1, width, height);
+
+ /* set up gimp drawable for rendering preview into */
+ src_image_id = gimp_item_get_image (drawable->drawable_id);
+ image_id = gimp_image_new (width, height,
+ gimp_image_base_type (src_image_id));
+ preview_id = gimp_layer_new (image_id, "preview", width, height,
+ gimp_drawable_type (drawable->drawable_id),
+ 100,
+ gimp_image_get_default_new_layer_mode (image_id));
+ preview_drawable = gimp_drawable_get (preview_id);
+ gimp_image_insert_layer (image_id, preview_id, -1, 0);
+ gimp_layer_set_offsets (preview_id, 0, 0);
+ gimp_pixel_rgn_init (&preview_rgn, preview_drawable,
+ 0, 0, width, height, TRUE, TRUE);
+ gimp_pixel_rgn_set_rect (&preview_rgn, buffer,
+ 0, 0, width, height);
+ gimp_drawable_flush (preview_drawable);
+ gimp_drawable_merge_shadow (preview_id, TRUE);
+ gimp_drawable_update (preview_id, 0, 0, width, height);
+
+ dog (image_id, preview_drawable, dogvals.inner, dogvals.outer, FALSE);
+
+ gimp_pixel_rgn_get_rect (&preview_rgn, buffer,
+ 0, 0, width, height);
+
+ gimp_preview_draw_buffer (preview, buffer, width * bpp);
+
+ gimp_image_delete (image_id);
+ g_free (buffer);
+}
+
+static void
+change_radius_callback (GtkWidget *coord,
+ gpointer data)
+{
+ GimpPreview *preview = GIMP_PREVIEW (data);
+
+ dogvals.inner = gimp_size_entry_get_refval (GIMP_SIZE_ENTRY (coord), 0);
+ dogvals.outer = gimp_size_entry_get_refval (GIMP_SIZE_ENTRY (coord), 1);
+
+ gimp_preview_invalidate (preview);
+}