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-rw-r--r--app/core/gimplineart.c2979
1 files changed, 2979 insertions, 0 deletions
diff --git a/app/core/gimplineart.c b/app/core/gimplineart.c
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+++ b/app/core/gimplineart.c
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+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * Copyright (C) 2017 Sébastien Fourey & David Tchumperlé
+ * Copyright (C) 2018 Jehan
+ *
+ * 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/>.
+ */
+
+#include "config.h"
+
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gegl.h>
+
+#include "libgimpmath/gimpmath.h"
+
+#include "core-types.h"
+
+#include "gegl/gimp-gegl-loops.h"
+#include "gegl/gimp-gegl-utils.h"
+
+#include "gimp-parallel.h"
+#include "gimp-priorities.h"
+#include "gimp-utils.h" /* GIMP_TIMER */
+#include "gimpasync.h"
+#include "gimpcancelable.h"
+#include "gimpdrawable.h"
+#include "gimpimage.h"
+#include "gimplineart.h"
+#include "gimpmarshal.h"
+#include "gimppickable.h"
+#include "gimpprojection.h"
+#include "gimpviewable.h"
+#include "gimpwaitable.h"
+
+#include "gimp-intl.h"
+
+enum
+{
+ COMPUTING_START,
+ COMPUTING_END,
+ LAST_SIGNAL,
+};
+
+enum
+{
+ PROP_0,
+ PROP_SELECT_TRANSPARENT,
+ PROP_MAX_GROW,
+ PROP_THRESHOLD,
+ PROP_SPLINE_MAX_LEN,
+ PROP_SEGMENT_MAX_LEN,
+};
+
+typedef struct _GimpLineArtPrivate GimpLineArtPrivate;
+
+struct _GimpLineArtPrivate
+{
+ gboolean frozen;
+ gboolean compute_after_thaw;
+
+ GimpAsync *async;
+
+ gint idle_id;
+
+ GimpPickable *input;
+ GeglBuffer *closed;
+ gfloat *distmap;
+
+ /* Used in the closing step. */
+ gboolean select_transparent;
+ gdouble threshold;
+ gint spline_max_len;
+ gint segment_max_len;
+ gboolean max_len_bound;
+
+ /* Used in the grow step. */
+ gint max_grow;
+};
+
+typedef struct
+{
+ GeglBuffer *buffer;
+
+ gboolean select_transparent;
+ gdouble threshold;
+ gint spline_max_len;
+ gint segment_max_len;
+} LineArtData;
+
+typedef struct
+{
+ GeglBuffer *closed;
+ gfloat *distmap;
+} LineArtResult;
+
+static int DeltaX[4] = {+1, -1, 0, 0};
+static int DeltaY[4] = {0, 0, +1, -1};
+
+static const GimpVector2 Direction2Normal[4] =
+{
+ { 1.0f, 0.0f },
+ { -1.0f, 0.0f },
+ { 0.0f, 1.0f },
+ { 0.0f, -1.0f }
+};
+
+typedef enum _Direction
+{
+ XPlusDirection = 0,
+ XMinusDirection = 1,
+ YPlusDirection = 2,
+ YMinusDirection = 3
+} Direction;
+
+typedef GimpVector2 Pixel;
+
+typedef struct _SplineCandidate
+{
+ Pixel p1;
+ Pixel p2;
+ float quality;
+} SplineCandidate;
+
+typedef struct _Edgel
+{
+ gint x, y;
+ Direction direction;
+
+ gfloat x_normal;
+ gfloat y_normal;
+ gfloat curvature;
+ guint next, previous;
+} Edgel;
+
+
+static void gimp_line_art_finalize (GObject *object);
+static void gimp_line_art_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec);
+static void gimp_line_art_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec);
+
+/* Functions for asynchronous computation. */
+
+static void gimp_line_art_compute (GimpLineArt *line_art);
+static void gimp_line_art_compute_cb (GimpAsync *async,
+ GimpLineArt *line_art);
+
+static GimpAsync * gimp_line_art_prepare_async (GimpLineArt *line_art,
+ gint priority);
+static void gimp_line_art_prepare_async_func (GimpAsync *async,
+ LineArtData *data);
+static LineArtData * line_art_data_new (GeglBuffer *buffer,
+ GimpLineArt *line_art);
+static void line_art_data_free (LineArtData *data);
+static LineArtResult * line_art_result_new (GeglBuffer *line_art,
+ gfloat *distmap);
+static void line_art_result_free (LineArtResult *result);
+
+static gboolean gimp_line_art_idle (GimpLineArt *line_art);
+static void gimp_line_art_input_invalidate_preview (GimpViewable *viewable,
+ GimpLineArt *line_art);
+
+
+/* All actual computation functions. */
+
+static GeglBuffer * gimp_line_art_close (GeglBuffer *buffer,
+ gboolean select_transparent,
+ gdouble stroke_threshold,
+ gint spline_max_length,
+ gint segment_max_length,
+ gint minimal_lineart_area,
+ gint normal_estimate_mask_size,
+ gfloat end_point_rate,
+ gfloat spline_max_angle,
+ gint end_point_connectivity,
+ gfloat spline_roundness,
+ gboolean allow_self_intersections,
+ gint created_regions_significant_area,
+ gint created_regions_minimum_area,
+ gboolean small_segments_from_spline_sources,
+ gfloat **lineart_distmap,
+ GimpAsync *async);
+
+static void gimp_lineart_denoise (GeglBuffer *buffer,
+ int size,
+ GimpAsync *async);
+static void gimp_lineart_compute_normals_curvatures (GeglBuffer *mask,
+ gfloat *normals,
+ gfloat *curvatures,
+ gfloat *smoothed_curvatures,
+ int normal_estimate_mask_size,
+ GimpAsync *async);
+static gfloat * gimp_lineart_get_smooth_curvatures (GArray *edgelset,
+ GimpAsync *async);
+static GArray * gimp_lineart_curvature_extremums (gfloat *curvatures,
+ gfloat *smoothed_curvatures,
+ gint curvatures_width,
+ gint curvatures_height,
+ GimpAsync *async);
+static gint gimp_spline_candidate_cmp (const SplineCandidate *a,
+ const SplineCandidate *b,
+ gpointer user_data);
+static GList * gimp_lineart_find_spline_candidates (GArray *max_positions,
+ gfloat *normals,
+ gint width,
+ gint distance_threshold,
+ gfloat max_angle_deg,
+ GimpAsync *async);
+
+static GArray * gimp_lineart_discrete_spline (Pixel p0,
+ GimpVector2 n0,
+ Pixel p1,
+ GimpVector2 n1);
+
+static gint gimp_number_of_transitions (GArray *pixels,
+ GeglBuffer *buffer);
+static gboolean gimp_line_art_allow_closure (GeglBuffer *mask,
+ GArray *pixels,
+ GList **fill_pixels,
+ int significant_size,
+ int minimum_size);
+static GArray * gimp_lineart_line_segment_until_hit (const GeglBuffer *buffer,
+ Pixel start,
+ GimpVector2 direction,
+ int size);
+static gfloat * gimp_lineart_estimate_strokes_radii (GeglBuffer *mask,
+ GimpAsync *async);
+static void gimp_line_art_simple_fill (GeglBuffer *buffer,
+ gint x,
+ gint y,
+ gint *counter);
+
+/* Some callback-type functions. */
+
+static guint visited_hash_fun (Pixel *key);
+static gboolean visited_equal_fun (Pixel *e1,
+ Pixel *e2);
+
+static inline gboolean border_in_direction (GeglBuffer *mask,
+ Pixel p,
+ int direction);
+static inline GimpVector2 pair2normal (Pixel p,
+ gfloat *normals,
+ gint width);
+
+/* Edgel */
+
+static Edgel * gimp_edgel_new (int x,
+ int y,
+ Direction direction);
+static void gimp_edgel_init (Edgel *edgel);
+static void gimp_edgel_clear (Edgel **edgel);
+static int gimp_edgel_cmp (const Edgel *e1,
+ const Edgel *e2);
+static guint edgel2index_hash_fun (Edgel *key);
+static gboolean edgel2index_equal_fun (Edgel *e1,
+ Edgel *e2);
+
+static glong gimp_edgel_track_mark (GeglBuffer *mask,
+ Edgel edgel,
+ long size_limit);
+static glong gimp_edgel_region_area (const GeglBuffer *mask,
+ Edgel start_edgel);
+
+/* Edgel set */
+
+static GArray * gimp_edgelset_new (GeglBuffer *buffer,
+ GimpAsync *async);
+static void gimp_edgelset_add (GArray *set,
+ int x,
+ int y,
+ Direction direction,
+ GHashTable *edgel2index);
+static void gimp_edgelset_init_normals (GArray *set);
+static void gimp_edgelset_smooth_normals (GArray *set,
+ int mask_size,
+ GimpAsync *async);
+static void gimp_edgelset_compute_curvature (GArray *set,
+ GimpAsync *async);
+
+static void gimp_edgelset_build_graph (GArray *set,
+ GeglBuffer *buffer,
+ GHashTable *edgel2index,
+ GimpAsync *async);
+static void gimp_edgelset_next8 (const GeglBuffer *buffer,
+ Edgel *it,
+ Edgel *n);
+
+G_DEFINE_TYPE_WITH_CODE (GimpLineArt, gimp_line_art, GIMP_TYPE_OBJECT,
+ G_ADD_PRIVATE (GimpLineArt))
+
+static guint gimp_line_art_signals[LAST_SIGNAL] = { 0 };
+
+static void
+gimp_line_art_class_init (GimpLineArtClass *klass)
+{
+ GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+ gimp_line_art_signals[COMPUTING_START] =
+ g_signal_new ("computing-start",
+ G_TYPE_FROM_CLASS (klass),
+ G_SIGNAL_RUN_FIRST,
+ G_STRUCT_OFFSET (GimpLineArtClass, computing_start),
+ NULL, NULL,
+ gimp_marshal_VOID__VOID,
+ G_TYPE_NONE, 0);
+ gimp_line_art_signals[COMPUTING_END] =
+ g_signal_new ("computing-end",
+ G_TYPE_FROM_CLASS (klass),
+ G_SIGNAL_RUN_FIRST,
+ G_STRUCT_OFFSET (GimpLineArtClass, computing_end),
+ NULL, NULL,
+ gimp_marshal_VOID__VOID,
+ G_TYPE_NONE, 0);
+
+ object_class->finalize = gimp_line_art_finalize;
+ object_class->set_property = gimp_line_art_set_property;
+ object_class->get_property = gimp_line_art_get_property;
+
+ g_object_class_install_property (object_class, PROP_SELECT_TRANSPARENT,
+ g_param_spec_boolean ("select-transparent",
+ _("Select transparent pixels instead of gray ones"),
+ _("Select transparent pixels instead of gray ones"),
+ TRUE,
+ G_PARAM_CONSTRUCT | GIMP_PARAM_READWRITE));
+
+ g_object_class_install_property (object_class, PROP_THRESHOLD,
+ g_param_spec_double ("threshold",
+ _("Line art detection threshold"),
+ _("Threshold to detect contour (higher values will include more pixels)"),
+ 0.0, 1.0, 0.92,
+ G_PARAM_CONSTRUCT | GIMP_PARAM_READWRITE));
+
+ g_object_class_install_property (object_class, PROP_MAX_GROW,
+ g_param_spec_int ("max-grow",
+ _("Maximum growing size"),
+ _("Maximum number of pixels grown under the line art"),
+ 1, 100, 3,
+ G_PARAM_CONSTRUCT | GIMP_PARAM_READWRITE));
+
+ g_object_class_install_property (object_class, PROP_SPLINE_MAX_LEN,
+ g_param_spec_int ("spline-max-length",
+ _("Maximum curved closing length"),
+ _("Maximum curved length (in pixels) to close the line art"),
+ 0, 1000, 100,
+ G_PARAM_CONSTRUCT | GIMP_PARAM_READWRITE));
+
+ g_object_class_install_property (object_class, PROP_SEGMENT_MAX_LEN,
+ g_param_spec_int ("segment-max-length",
+ _("Maximum straight closing length"),
+ _("Maximum straight length (in pixels) to close the line art"),
+ 0, 1000, 100,
+ G_PARAM_CONSTRUCT | GIMP_PARAM_READWRITE));
+}
+
+static void
+gimp_line_art_init (GimpLineArt *line_art)
+{
+ line_art->priv = gimp_line_art_get_instance_private (line_art);
+}
+
+static void
+gimp_line_art_finalize (GObject *object)
+{
+ GimpLineArt *line_art = GIMP_LINE_ART (object);
+
+ line_art->priv->frozen = FALSE;
+
+ gimp_line_art_set_input (line_art, NULL);
+}
+
+static void
+gimp_line_art_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ GimpLineArt *line_art = GIMP_LINE_ART (object);
+
+ switch (property_id)
+ {
+ case PROP_SELECT_TRANSPARENT:
+ if (line_art->priv->select_transparent != g_value_get_boolean (value))
+ {
+ line_art->priv->select_transparent = g_value_get_boolean (value);
+ gimp_line_art_compute (line_art);
+ }
+ break;
+ case PROP_MAX_GROW:
+ line_art->priv->max_grow = g_value_get_int (value);
+ break;
+ case PROP_THRESHOLD:
+ if (line_art->priv->threshold != g_value_get_double (value))
+ {
+ line_art->priv->threshold = g_value_get_double (value);
+ gimp_line_art_compute (line_art);
+ }
+ break;
+ case PROP_SPLINE_MAX_LEN:
+ if (line_art->priv->spline_max_len != g_value_get_int (value))
+ {
+ line_art->priv->spline_max_len = g_value_get_int (value);
+ if (line_art->priv->max_len_bound)
+ line_art->priv->segment_max_len = line_art->priv->spline_max_len;
+ gimp_line_art_compute (line_art);
+ }
+ break;
+ case PROP_SEGMENT_MAX_LEN:
+ if (line_art->priv->segment_max_len != g_value_get_int (value))
+ {
+ line_art->priv->segment_max_len = g_value_get_int (value);
+ if (line_art->priv->max_len_bound)
+ line_art->priv->spline_max_len = line_art->priv->segment_max_len;
+ gimp_line_art_compute (line_art);
+ }
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static void
+gimp_line_art_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ GimpLineArt *line_art = GIMP_LINE_ART (object);
+
+ switch (property_id)
+ {
+ case PROP_SELECT_TRANSPARENT:
+ g_value_set_boolean (value, line_art->priv->select_transparent);
+ break;
+ case PROP_MAX_GROW:
+ g_value_set_int (value, line_art->priv->max_grow);
+ break;
+ case PROP_THRESHOLD:
+ g_value_set_double (value, line_art->priv->threshold);
+ break;
+ case PROP_SPLINE_MAX_LEN:
+ g_value_set_int (value, line_art->priv->spline_max_len);
+ break;
+ case PROP_SEGMENT_MAX_LEN:
+ g_value_set_int (value, line_art->priv->segment_max_len);
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+/* Public functions */
+
+GimpLineArt *
+gimp_line_art_new (void)
+{
+ return g_object_new (GIMP_TYPE_LINE_ART,
+ NULL);
+}
+
+void
+gimp_line_art_bind_gap_length (GimpLineArt *line_art,
+ gboolean bound)
+{
+ line_art->priv->max_len_bound = bound;
+}
+
+void
+gimp_line_art_set_input (GimpLineArt *line_art,
+ GimpPickable *pickable)
+{
+ g_return_if_fail (pickable == NULL || GIMP_IS_VIEWABLE (pickable));
+
+ if (pickable != line_art->priv->input)
+ {
+ if (line_art->priv->input)
+ g_signal_handlers_disconnect_by_data (line_art->priv->input, line_art);
+
+ g_set_object (&line_art->priv->input, pickable);
+
+ gimp_line_art_compute (line_art);
+
+ if (pickable)
+ {
+ g_signal_connect (pickable, "invalidate-preview",
+ G_CALLBACK (gimp_line_art_input_invalidate_preview),
+ line_art);
+ }
+ }
+}
+
+GimpPickable *
+gimp_line_art_get_input (GimpLineArt *line_art)
+{
+ return line_art->priv->input;
+}
+
+void
+gimp_line_art_freeze (GimpLineArt *line_art)
+{
+ g_return_if_fail (! line_art->priv->frozen);
+
+ line_art->priv->frozen = TRUE;
+ line_art->priv->compute_after_thaw = FALSE;
+}
+
+void
+gimp_line_art_thaw (GimpLineArt *line_art)
+{
+ g_return_if_fail (line_art->priv->frozen);
+
+ line_art->priv->frozen = FALSE;
+ if (line_art->priv->compute_after_thaw)
+ {
+ gimp_line_art_compute (line_art);
+ line_art->priv->compute_after_thaw = FALSE;
+ }
+}
+
+gboolean
+gimp_line_art_is_frozen (GimpLineArt *line_art)
+{
+ return line_art->priv->frozen;
+}
+
+GeglBuffer *
+gimp_line_art_get (GimpLineArt *line_art,
+ gfloat **distmap)
+{
+ g_return_val_if_fail (line_art->priv->input, NULL);
+
+ if (line_art->priv->async)
+ {
+ gimp_waitable_wait (GIMP_WAITABLE (line_art->priv->async));
+ }
+ else if (! line_art->priv->closed)
+ {
+ gimp_line_art_compute (line_art);
+ if (line_art->priv->async)
+ gimp_waitable_wait (GIMP_WAITABLE (line_art->priv->async));
+ }
+
+ g_return_val_if_fail (line_art->priv->closed, NULL);
+
+ if (distmap)
+ *distmap = line_art->priv->distmap;
+
+ return line_art->priv->closed;
+}
+
+/* Functions for asynchronous computation. */
+
+static void
+gimp_line_art_compute (GimpLineArt *line_art)
+{
+ if (line_art->priv->frozen)
+ {
+ line_art->priv->compute_after_thaw = TRUE;
+ return;
+ }
+
+ if (line_art->priv->async)
+ {
+ /* we cancel the async, but don't wait for it to finish, since
+ * it might take a while to respond. instead gimp_line_art_compute_cb()
+ * bails if the async has been canceled, to avoid accessing the line art.
+ */
+ g_signal_emit (line_art, gimp_line_art_signals[COMPUTING_END], 0);
+ gimp_cancelable_cancel (GIMP_CANCELABLE (line_art->priv->async));
+ g_clear_object (&line_art->priv->async);
+ }
+
+ if (line_art->priv->idle_id)
+ {
+ g_source_remove (line_art->priv->idle_id);
+ line_art->priv->idle_id = 0;
+ }
+
+ g_clear_object (&line_art->priv->closed);
+ g_clear_pointer (&line_art->priv->distmap, g_free);
+
+ if (line_art->priv->input)
+ {
+ /* gimp_line_art_prepare_async() will flush the pickable, which
+ * may trigger this signal handler, and will leak a line art (as
+ * line_art->priv->async has not been set yet).
+ */
+ g_signal_handlers_block_by_func (
+ line_art->priv->input,
+ G_CALLBACK (gimp_line_art_input_invalidate_preview),
+ line_art);
+ line_art->priv->async = gimp_line_art_prepare_async (line_art, +1);
+ g_signal_emit (line_art, gimp_line_art_signals[COMPUTING_START], 0);
+ g_signal_handlers_unblock_by_func (
+ line_art->priv->input,
+ G_CALLBACK (gimp_line_art_input_invalidate_preview),
+ line_art);
+
+ gimp_async_add_callback_for_object (line_art->priv->async,
+ (GimpAsyncCallback) gimp_line_art_compute_cb,
+ line_art, line_art);
+ }
+}
+
+static void
+gimp_line_art_compute_cb (GimpAsync *async,
+ GimpLineArt *line_art)
+{
+ if (gimp_async_is_canceled (async))
+ return;
+
+ if (gimp_async_is_finished (async))
+ {
+ LineArtResult *result;
+
+ result = gimp_async_get_result (async);
+
+ line_art->priv->closed = g_object_ref (result->closed);
+ line_art->priv->distmap = result->distmap;
+ result->distmap = NULL;
+ g_signal_emit (line_art, gimp_line_art_signals[COMPUTING_END], 0);
+ }
+
+ g_clear_object (&line_art->priv->async);
+}
+
+static GimpAsync *
+gimp_line_art_prepare_async (GimpLineArt *line_art,
+ gint priority)
+{
+ GeglBuffer *buffer;
+ GimpAsync *async;
+ LineArtData *data;
+
+ g_return_val_if_fail (GIMP_IS_PICKABLE (line_art->priv->input), NULL);
+
+ gimp_pickable_flush (line_art->priv->input);
+
+ buffer = gimp_gegl_buffer_dup (
+ gimp_pickable_get_buffer (line_art->priv->input));
+
+ data = line_art_data_new (buffer, line_art);
+
+ g_object_unref (buffer);
+
+ async = gimp_parallel_run_async_full (
+ priority,
+ (GimpRunAsyncFunc) gimp_line_art_prepare_async_func,
+ data, (GDestroyNotify) line_art_data_free);
+
+ return async;
+}
+
+static void
+gimp_line_art_prepare_async_func (GimpAsync *async,
+ LineArtData *data)
+{
+ GeglBuffer *buffer;
+ GeglBuffer *closed = NULL;
+ gfloat *distmap = NULL;
+ gint buffer_x;
+ gint buffer_y;
+ gboolean has_alpha;
+ gboolean select_transparent = FALSE;
+
+ has_alpha = babl_format_has_alpha (gegl_buffer_get_format (data->buffer));
+
+ if (has_alpha)
+ {
+ if (data->select_transparent)
+ {
+ /* don't select transparent regions if there are no fully
+ * transparent pixels.
+ */
+ GeglBufferIterator *gi;
+
+ gi = gegl_buffer_iterator_new (data->buffer, NULL, 0,
+ babl_format ("A u8"),
+ GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 3);
+ while (gegl_buffer_iterator_next (gi))
+ {
+ guint8 *p = (guint8*) gi->items[0].data;
+ gint k;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gegl_buffer_iterator_stop (gi);
+
+ gimp_async_abort (async);
+
+ line_art_data_free (data);
+
+ return;
+ }
+
+ for (k = 0; k < gi->length; k++)
+ {
+ if (! *p)
+ {
+ select_transparent = TRUE;
+ break;
+ }
+ p++;
+ }
+ if (select_transparent)
+ break;
+ }
+ if (select_transparent)
+ gegl_buffer_iterator_stop (gi);
+ }
+ }
+
+ buffer = data->buffer;
+ buffer_x = gegl_buffer_get_x (data->buffer);
+ buffer_y = gegl_buffer_get_y (data->buffer);
+
+ if (buffer_x != 0 || buffer_y != 0)
+ {
+ buffer = g_object_new (GEGL_TYPE_BUFFER,
+ "source", buffer,
+ "shift-x", buffer_x,
+ "shift-y", buffer_y,
+ NULL);
+ }
+
+ /* For smart selection, we generate a binarized image with close
+ * regions, then run a composite selection with no threshold on
+ * this intermediate buffer.
+ */
+ GIMP_TIMER_START();
+
+ closed = gimp_line_art_close (buffer,
+ select_transparent,
+ data->threshold,
+ data->spline_max_len,
+ data->segment_max_len,
+ /*minimal_lineart_area,*/
+ 5,
+ /*normal_estimate_mask_size,*/
+ 5,
+ /*end_point_rate,*/
+ 0.85,
+ /*spline_max_angle,*/
+ 90.0,
+ /*end_point_connectivity,*/
+ 2,
+ /*spline_roundness,*/
+ 1.0,
+ /*allow_self_intersections,*/
+ TRUE,
+ /*created_regions_significant_area,*/
+ 4,
+ /*created_regions_minimum_area,*/
+ 100,
+ /*small_segments_from_spline_sources,*/
+ TRUE,
+ &distmap,
+ async);
+
+ GIMP_TIMER_END("close line-art");
+
+ if (buffer != data->buffer)
+ g_object_unref (buffer);
+
+ if (! gimp_async_is_stopped (async))
+ {
+ if (buffer_x != 0 || buffer_y != 0)
+ {
+ buffer = g_object_new (GEGL_TYPE_BUFFER,
+ "source", closed,
+ "shift-x", -buffer_x,
+ "shift-y", -buffer_y,
+ NULL);
+
+ g_object_unref (closed);
+
+ closed = buffer;
+ }
+
+ gimp_async_finish_full (async,
+ line_art_result_new (closed, distmap),
+ (GDestroyNotify) line_art_result_free);
+ }
+
+ line_art_data_free (data);
+}
+
+static LineArtData *
+line_art_data_new (GeglBuffer *buffer,
+ GimpLineArt *line_art)
+{
+ LineArtData *data = g_slice_new (LineArtData);
+
+ data->buffer = g_object_ref (buffer);
+ data->select_transparent = line_art->priv->select_transparent;
+ data->threshold = line_art->priv->threshold;
+ data->spline_max_len = line_art->priv->spline_max_len;
+ data->segment_max_len = line_art->priv->segment_max_len;
+
+ return data;
+}
+
+static void
+line_art_data_free (LineArtData *data)
+{
+ g_object_unref (data->buffer);
+
+ g_slice_free (LineArtData, data);
+}
+
+static LineArtResult *
+line_art_result_new (GeglBuffer *closed,
+ gfloat *distmap)
+{
+ LineArtResult *data;
+
+ data = g_slice_new (LineArtResult);
+ data->closed = closed;
+ data->distmap = distmap;
+
+ return data;
+}
+
+static void
+line_art_result_free (LineArtResult *data)
+{
+ g_object_unref (data->closed);
+ g_clear_pointer (&data->distmap, g_free);
+
+ g_slice_free (LineArtResult, data);
+}
+
+static gboolean
+gimp_line_art_idle (GimpLineArt *line_art)
+{
+ line_art->priv->idle_id = 0;
+
+ gimp_line_art_compute (line_art);
+
+ return G_SOURCE_REMOVE;
+}
+
+static void
+gimp_line_art_input_invalidate_preview (GimpViewable *viewable,
+ GimpLineArt *line_art)
+{
+ if (! line_art->priv->idle_id)
+ {
+ line_art->priv->idle_id = g_idle_add_full (
+ GIMP_PRIORITY_VIEWABLE_IDLE,
+ (GSourceFunc) gimp_line_art_idle,
+ line_art, NULL);
+ }
+}
+
+/* All actual computation functions. */
+
+/**
+ * gimp_line_art_close:
+ * @buffer: the input #GeglBuffer.
+ * @select_transparent: whether we binarize the alpha channel or the
+ * luminosity.
+ * @stroke_threshold: [0-1] threshold value for detecting stroke pixels
+ * (higher values will detect more stroke pixels).
+ * @spline_max_length: the maximum length for creating splines between
+ * end points.
+ * @segment_max_length: the maximum length for creating segments
+ * between end points. Unlike splines, segments
+ * are straight lines.
+ * @minimal_lineart_area: the minimum size in number pixels for area to
+ * be considered as line art.
+ * @normal_estimate_mask_size:
+ * @end_point_rate: threshold to estimate if a curvature is an end-point
+ * in [0-1] range value.
+ * @spline_max_angle: the maximum angle between end point normals for
+ * creating splines between them.
+ * @end_point_connectivity:
+ * @spline_roundness:
+ * @allow_self_intersections: whether to allow created splines and
+ * segments to intersect.
+ * @created_regions_significant_area:
+ * @created_regions_minimum_area:
+ * @small_segments_from_spline_sources:
+ * @closed_distmap: a distance map of the closed line art pixels.
+ * @async: the #GimpAsync associated with the computation
+ *
+ * Creates a binarized version of the strokes of @buffer, detected either
+ * with luminosity (light means background) or alpha values depending on
+ * @select_transparent. This binary version of the strokes will have closed
+ * regions allowing adequate selection of "nearly closed regions".
+ * This algorithm is meant for digital painting (and in particular on the
+ * sketch-only step), and therefore will likely produce unexpected results on
+ * other types of input.
+ *
+ * The algorithm is the first step from the research paper "A Fast and
+ * Efficient Semi-guided Algorithm for Flat Coloring Line-arts", by Sébastian
+ * Fourey, David Tschumperlé, David Revoy.
+ * https://hal.archives-ouvertes.fr/hal-01891876
+ *
+ * Returns: a new #GeglBuffer of format "Y u8" representing the
+ * binarized @line_art. If @lineart_distmap is not #NULL, a
+ * newly allocated float buffer is returned, which can be used
+ * for overflowing created masks later.
+ */
+static GeglBuffer *
+gimp_line_art_close (GeglBuffer *buffer,
+ gboolean select_transparent,
+ gdouble stroke_threshold,
+ gint spline_max_length,
+ gint segment_max_length,
+ gint minimal_lineart_area,
+ gint normal_estimate_mask_size,
+ gfloat end_point_rate,
+ gfloat spline_max_angle,
+ gint end_point_connectivity,
+ gfloat spline_roundness,
+ gboolean allow_self_intersections,
+ gint created_regions_significant_area,
+ gint created_regions_minimum_area,
+ gboolean small_segments_from_spline_sources,
+ gfloat **closed_distmap,
+ GimpAsync *async)
+{
+ const Babl *gray_format;
+ GeglBufferIterator *gi;
+ GeglBuffer *closed = NULL;
+ GeglBuffer *strokes = NULL;
+ guchar max_value = 0;
+ gint width = gegl_buffer_get_width (buffer);
+ gint height = gegl_buffer_get_height (buffer);
+ gint i;
+
+ if (select_transparent)
+ /* Keep alpha channel as gray levels */
+ gray_format = babl_format ("A u8");
+ else
+ /* Keep luminance */
+ gray_format = babl_format ("Y' u8");
+
+ /* Transform the line art from any format to gray. */
+ strokes = gegl_buffer_new (gegl_buffer_get_extent (buffer),
+ gray_format);
+ gimp_gegl_buffer_copy (buffer, NULL, GEGL_ABYSS_NONE, strokes, NULL);
+ gegl_buffer_set_format (strokes, babl_format ("Y' u8"));
+
+ if (! select_transparent)
+ {
+ /* Compute the biggest value */
+ gi = gegl_buffer_iterator_new (strokes, NULL, 0, NULL,
+ GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 1);
+ while (gegl_buffer_iterator_next (gi))
+ {
+ guchar *data = (guchar*) gi->items[0].data;
+ gint k;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gegl_buffer_iterator_stop (gi);
+
+ gimp_async_abort (async);
+
+ goto end1;
+ }
+
+ for (k = 0; k < gi->length; k++)
+ {
+ if (*data > max_value)
+ max_value = *data;
+ data++;
+ }
+ }
+ }
+
+ /* Make the image binary: 1 is stroke, 0 background */
+ gi = gegl_buffer_iterator_new (strokes, NULL, 0, NULL,
+ GEGL_ACCESS_READWRITE, GEGL_ABYSS_NONE, 1);
+ while (gegl_buffer_iterator_next (gi))
+ {
+ guchar *data = (guchar*) gi->items[0].data;
+ gint k;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gegl_buffer_iterator_stop (gi);
+
+ gimp_async_abort (async);
+
+ goto end1;
+ }
+
+ for (k = 0; k < gi->length; k++)
+ {
+ if (! select_transparent)
+ /* Negate the value. */
+ *data = max_value - *data;
+ /* Apply a threshold. */
+ if (*data > (guchar) (255.0f * (1.0f - stroke_threshold)))
+ *data = 1;
+ else
+ *data = 0;
+ data++;
+ }
+ }
+
+ /* Denoise (remove small connected components) */
+ gimp_lineart_denoise (strokes, minimal_lineart_area, async);
+ if (gimp_async_is_stopped (async))
+ goto end1;
+
+ closed = g_object_ref (strokes);
+
+ if (spline_max_length > 0 || segment_max_length > 0)
+ {
+ GArray *keypoints = NULL;
+ GHashTable *visited = NULL;
+ gfloat *radii = NULL;
+ gfloat *normals = NULL;
+ gfloat *curvatures = NULL;
+ gfloat *smoothed_curvatures = NULL;
+ gfloat threshold;
+ gfloat clamped_threshold;
+ GList *fill_pixels = NULL;
+ GList *iter;
+
+ normals = g_new0 (gfloat, width * height * 2);
+ curvatures = g_new0 (gfloat, width * height);
+ smoothed_curvatures = g_new0 (gfloat, width * height);
+
+ /* Estimate normals & curvature */
+ gimp_lineart_compute_normals_curvatures (strokes, normals, curvatures,
+ smoothed_curvatures,
+ normal_estimate_mask_size,
+ async);
+ if (gimp_async_is_stopped (async))
+ goto end2;
+
+ radii = gimp_lineart_estimate_strokes_radii (strokes, async);
+ if (gimp_async_is_stopped (async))
+ goto end2;
+ threshold = 1.0f - end_point_rate;
+ clamped_threshold = MAX (0.25f, threshold);
+ for (i = 0; i < width; i++)
+ {
+ gint j;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end2;
+ }
+
+ for (j = 0; j < height; j++)
+ {
+ if (smoothed_curvatures[i + j * width] >= (threshold / MAX (1.0f, radii[i + j * width])) ||
+ curvatures[i + j * width] >= clamped_threshold)
+ curvatures[i + j * width] = 1.0;
+ else
+ curvatures[i + j * width] = 0.0;
+ }
+ }
+ g_clear_pointer (&radii, g_free);
+
+ keypoints = gimp_lineart_curvature_extremums (curvatures, smoothed_curvatures,
+ width, height, async);
+ if (gimp_async_is_stopped (async))
+ goto end2;
+
+ visited = g_hash_table_new_full ((GHashFunc) visited_hash_fun,
+ (GEqualFunc) visited_equal_fun,
+ (GDestroyNotify) g_free, NULL);
+
+ if (spline_max_length > 0)
+ {
+ GList *candidates;
+ SplineCandidate *candidate;
+
+ candidates = gimp_lineart_find_spline_candidates (keypoints, normals, width,
+ spline_max_length,
+ spline_max_angle,
+ async);
+ if (gimp_async_is_stopped (async))
+ goto end3;
+
+ g_object_unref (closed);
+ closed = gimp_gegl_buffer_dup (strokes);
+
+ /* Draw splines */
+ while (candidates)
+ {
+ Pixel *p1;
+ Pixel *p2;
+ gboolean inserted = FALSE;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end3;
+ }
+
+ p1 = g_new (Pixel, 1);
+ p2 = g_new (Pixel, 1);
+
+ candidate = (SplineCandidate *) candidates->data;
+ p1->x = candidate->p1.x;
+ p1->y = candidate->p1.y;
+ p2->x = candidate->p2.x;
+ p2->y = candidate->p2.y;
+
+ g_free (candidate);
+ candidates = g_list_delete_link (candidates, candidates);
+
+ if ((! g_hash_table_contains (visited, p1) ||
+ GPOINTER_TO_INT (g_hash_table_lookup (visited, p1)) < end_point_connectivity) &&
+ (! g_hash_table_contains (visited, p2) ||
+ GPOINTER_TO_INT (g_hash_table_lookup (visited, p2)) < end_point_connectivity))
+ {
+ GArray *discrete_curve;
+ GimpVector2 vect1 = pair2normal (*p1, normals, width);
+ GimpVector2 vect2 = pair2normal (*p2, normals, width);
+ gfloat distance = gimp_vector2_length_val (gimp_vector2_sub_val (*p1, *p2));
+ gint transitions;
+
+ gimp_vector2_mul (&vect1, distance);
+ gimp_vector2_mul (&vect1, spline_roundness);
+ gimp_vector2_mul (&vect2, distance);
+ gimp_vector2_mul (&vect2, spline_roundness);
+
+ discrete_curve = gimp_lineart_discrete_spline (*p1, vect1, *p2, vect2);
+
+ transitions = allow_self_intersections ?
+ gimp_number_of_transitions (discrete_curve, strokes) :
+ gimp_number_of_transitions (discrete_curve, closed);
+
+ if (transitions == 2 &&
+ gimp_line_art_allow_closure (closed, discrete_curve,
+ &fill_pixels,
+ created_regions_significant_area,
+ created_regions_minimum_area))
+ {
+ for (i = 0; i < discrete_curve->len; i++)
+ {
+ Pixel p = g_array_index (discrete_curve, Pixel, i);
+
+ if (p.x >= 0 && p.x < gegl_buffer_get_width (closed) &&
+ p.y >= 0 && p.y < gegl_buffer_get_height (closed))
+ {
+ guchar val = 2;
+
+ gegl_buffer_set (closed, GEGL_RECTANGLE ((gint) p.x, (gint) p.y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ }
+ g_hash_table_replace (visited, p1,
+ GINT_TO_POINTER (GPOINTER_TO_INT (g_hash_table_lookup (visited, p1)) + 1));
+ g_hash_table_replace (visited, p2,
+ GINT_TO_POINTER (GPOINTER_TO_INT (g_hash_table_lookup (visited, p2)) + 1));
+ inserted = TRUE;
+ }
+ g_array_free (discrete_curve, TRUE);
+ }
+ if (! inserted)
+ {
+ g_free (p1);
+ g_free (p2);
+ }
+ }
+
+ end3:
+ g_list_free_full (candidates, g_free);
+
+ if (gimp_async_is_stopped (async))
+ goto end2;
+ }
+
+ g_clear_object (&strokes);
+
+ /* Draw straight line segments */
+ if (segment_max_length > 0)
+ {
+ Pixel *point;
+
+ point = (Pixel *) keypoints->data;
+ for (i = 0; i < keypoints->len; i++)
+ {
+ Pixel *p;
+ gboolean inserted = FALSE;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end2;
+ }
+
+ p = g_new (Pixel, 1);
+ *p = *point;
+
+ if (! g_hash_table_contains (visited, p) ||
+ (small_segments_from_spline_sources &&
+ GPOINTER_TO_INT (g_hash_table_lookup (visited, p)) < end_point_connectivity))
+ {
+ GArray *segment = gimp_lineart_line_segment_until_hit (closed, *point,
+ pair2normal (*point, normals, width),
+ segment_max_length);
+
+ if (segment->len &&
+ gimp_line_art_allow_closure (closed, segment, &fill_pixels,
+ created_regions_significant_area,
+ created_regions_minimum_area))
+ {
+ gint j;
+
+ for (j = 0; j < segment->len; j++)
+ {
+ Pixel p2 = g_array_index (segment, Pixel, j);
+ guchar val = 2;
+
+ gegl_buffer_set (closed, GEGL_RECTANGLE ((gint) p2.x, (gint) p2.y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ g_hash_table_replace (visited, p,
+ GINT_TO_POINTER (GPOINTER_TO_INT (g_hash_table_lookup (visited, p)) + 1));
+ inserted = TRUE;
+ }
+ g_array_free (segment, TRUE);
+ }
+ if (! inserted)
+ g_free (p);
+ point++;
+ }
+ }
+
+ for (iter = fill_pixels; iter; iter = iter->next)
+ {
+ Pixel *p = iter->data;
+ gint fill_max = created_regions_significant_area - 1;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end2;
+ }
+
+ /* XXX A best approach would be to generalize
+ * gimp_drawable_bucket_fill() to work on any buffer (the code
+ * is already mostly there) rather than reimplementing a naive
+ * bucket fill.
+ * This is mostly a quick'n dirty first implementation which I
+ * will improve later.
+ */
+ gimp_line_art_simple_fill (closed, (gint) p->x, (gint) p->y, &fill_max);
+ }
+
+ end2:
+ g_list_free_full (fill_pixels, g_free);
+ g_free (normals);
+ g_free (curvatures);
+ g_free (smoothed_curvatures);
+ g_clear_pointer (&radii, g_free);
+ if (keypoints)
+ g_array_free (keypoints, TRUE);
+ g_clear_pointer (&visited, g_hash_table_destroy);
+
+ if (gimp_async_is_stopped (async))
+ goto end1;
+ }
+ else
+ {
+ g_clear_object (&strokes);
+ }
+
+ if (closed_distmap)
+ {
+ GeglNode *graph;
+ GeglNode *input;
+ GeglNode *op;
+
+ /* Flooding needs a distance map for closed line art. */
+ *closed_distmap = g_new (gfloat, width * height);
+
+ graph = gegl_node_new ();
+ input = gegl_node_new_child (graph,
+ "operation", "gegl:buffer-source",
+ "buffer", closed,
+ NULL);
+ op = gegl_node_new_child (graph,
+ "operation", "gegl:distance-transform",
+ "metric", GEGL_DISTANCE_METRIC_EUCLIDEAN,
+ "normalize", FALSE,
+ NULL);
+ gegl_node_connect_to (input, "output",
+ op, "input");
+ gegl_node_blit (op, 1.0, gegl_buffer_get_extent (closed),
+ NULL, *closed_distmap,
+ GEGL_AUTO_ROWSTRIDE, GEGL_BLIT_DEFAULT);
+ g_object_unref (graph);
+ }
+
+ end1:
+ g_clear_object (&strokes);
+
+ if (gimp_async_is_stopped (async))
+ g_clear_object (&closed);
+
+ return closed;
+}
+
+static void
+gimp_lineart_denoise (GeglBuffer *buffer,
+ int minimum_area,
+ GimpAsync *async)
+{
+ /* Keep connected regions with significant area. */
+ GArray *region;
+ GQueue *q = g_queue_new ();
+ gint width = gegl_buffer_get_width (buffer);
+ gint height = gegl_buffer_get_height (buffer);
+ gboolean *visited = g_new0 (gboolean, width * height);
+ gint x, y;
+
+ region = g_array_sized_new (TRUE, TRUE, sizeof (Pixel *), minimum_area);
+
+ for (y = 0; y < height; ++y)
+ for (x = 0; x < width; ++x)
+ {
+ guchar has_stroke;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ gegl_buffer_sample (buffer, x, y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[x + y * width])
+ {
+ Pixel *p = g_new (Pixel, 1);
+ gint regionSize = 0;
+
+ p->x = x;
+ p->y = y;
+
+ g_queue_push_tail (q, p);
+ visited[x + y * width] = TRUE;
+
+ while (! g_queue_is_empty (q))
+ {
+ Pixel *p;
+ gint p2x;
+ gint p2y;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ p = (Pixel *) g_queue_pop_head (q);
+
+ p2x = p->x + 1;
+ p2y = p->y;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x +p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x - 1;
+ p2y = p->y;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x + 1;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x - 1;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x - 1;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+ p2x = p->x + 1;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width && p2y >= 0 && p2y < height)
+ {
+ gegl_buffer_sample (buffer, p2x, p2y, NULL, &has_stroke, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (has_stroke && ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+ }
+
+ ++regionSize;
+ if (regionSize < minimum_area)
+ g_array_append_val (region, *p);
+ g_free (p);
+ }
+ if (regionSize < minimum_area)
+ {
+ Pixel *pixel = (Pixel *) region->data;
+ gint i = 0;
+
+ for (; i < region->len; i++)
+ {
+ guchar val = 0;
+ gegl_buffer_set (buffer, GEGL_RECTANGLE (pixel->x, pixel->y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ pixel++;
+ }
+ }
+ g_array_remove_range (region, 0, region->len);
+ }
+ }
+
+ end:
+ g_array_free (region, TRUE);
+ g_queue_free_full (q, g_free);
+ g_free (visited);
+}
+
+static void
+gimp_lineart_compute_normals_curvatures (GeglBuffer *mask,
+ gfloat *normals,
+ gfloat *curvatures,
+ gfloat *smoothed_curvatures,
+ int normal_estimate_mask_size,
+ GimpAsync *async)
+{
+ gfloat *edgels_curvatures = NULL;
+ gfloat *smoothed_curvature;
+ GArray *es = NULL;
+ Edgel **e;
+ gint width = gegl_buffer_get_width (mask);
+
+ es = gimp_edgelset_new (mask, async);
+ if (gimp_async_is_stopped (async))
+ goto end;
+
+ e = (Edgel **) es->data;
+
+ gimp_edgelset_smooth_normals (es, normal_estimate_mask_size, async);
+ if (gimp_async_is_stopped (async))
+ goto end;
+
+ gimp_edgelset_compute_curvature (es, async);
+ if (gimp_async_is_stopped (async))
+ goto end;
+
+ while (*e)
+ {
+ const float curvature = ((*e)->curvature > 0.0f) ? (*e)->curvature : 0.0f;
+ const float w = MAX (1e-8f, curvature * curvature);
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ normals[((*e)->x + (*e)->y * width) * 2] += w * (*e)->x_normal;
+ normals[((*e)->x + (*e)->y * width) * 2 + 1] += w * (*e)->y_normal;
+ curvatures[(*e)->x + (*e)->y * width] = MAX (curvature,
+ curvatures[(*e)->x + (*e)->y * width]);
+ e++;
+ }
+ for (int y = 0; y < gegl_buffer_get_height (mask); ++y)
+ {
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ for (int x = 0; x < gegl_buffer_get_width (mask); ++x)
+ {
+ const float _angle = atan2f (normals[(x + y * width) * 2 + 1],
+ normals[(x + y * width) * 2]);
+ normals[(x + y * width) * 2] = cosf (_angle);
+ normals[(x + y * width) * 2 + 1] = sinf (_angle);
+ }
+ }
+
+ /* Smooth curvatures on edgels, then take maximum on each pixel. */
+ edgels_curvatures = gimp_lineart_get_smooth_curvatures (es, async);
+ if (gimp_async_is_stopped (async))
+ goto end;
+
+ smoothed_curvature = edgels_curvatures;
+
+ e = (Edgel **) es->data;
+ while (*e)
+ {
+ gfloat *pixel_curvature = &smoothed_curvatures[(*e)->x + (*e)->y * width];
+
+ if (*pixel_curvature < *smoothed_curvature)
+ *pixel_curvature = *smoothed_curvature;
+
+ ++smoothed_curvature;
+ e++;
+ }
+
+ end:
+ g_free (edgels_curvatures);
+
+ if (es)
+ g_array_free (es, TRUE);
+}
+
+static gfloat *
+gimp_lineart_get_smooth_curvatures (GArray *edgelset,
+ GimpAsync *async)
+{
+ Edgel **e;
+ gfloat *smoothed_curvatures = g_new0 (gfloat, edgelset->len);
+ gfloat weights[9];
+ gfloat smoothed_curvature;
+ gfloat weights_sum;
+ gint idx = 0;
+
+ weights[0] = 1.0f;
+ for (int i = 1; i <= 8; ++i)
+ weights[i] = expf (-(i * i) / 30.0f);
+
+ e = (Edgel **) edgelset->data;
+ while (*e)
+ {
+ Edgel *edgel_before = g_array_index (edgelset, Edgel*, (*e)->previous);
+ Edgel *edgel_after = g_array_index (edgelset, Edgel*, (*e)->next);
+ int n = 5;
+ int i = 1;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ g_free (smoothed_curvatures);
+
+ return NULL;
+ }
+
+ smoothed_curvature = (*e)->curvature;
+ weights_sum = weights[0];
+ while (n-- && (edgel_after != edgel_before))
+ {
+ smoothed_curvature += weights[i] * edgel_before->curvature;
+ smoothed_curvature += weights[i] * edgel_after->curvature;
+ edgel_before = g_array_index (edgelset, Edgel*, edgel_before->previous);
+ edgel_after = g_array_index (edgelset, Edgel*, edgel_after->next);
+ weights_sum += 2 * weights[i];
+ i++;
+ }
+ smoothed_curvature /= weights_sum;
+ smoothed_curvatures[idx++] = smoothed_curvature;
+
+ e++;
+ }
+
+ return smoothed_curvatures;
+}
+
+/**
+ * Keep one pixel per connected component of curvature extremums.
+ */
+static GArray *
+gimp_lineart_curvature_extremums (gfloat *curvatures,
+ gfloat *smoothed_curvatures,
+ gint width,
+ gint height,
+ GimpAsync *async)
+{
+ gboolean *visited = g_new0 (gboolean, width * height);
+ GQueue *q = g_queue_new ();
+ GArray *max_positions;
+
+ max_positions = g_array_new (FALSE, TRUE, sizeof (Pixel));
+
+ for (int y = 0; y < height; ++y)
+ {
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ for (int x = 0; x < width; ++x)
+ {
+ if ((curvatures[x + y * width] > 0.0) && ! visited[x + y * width])
+ {
+ Pixel *p = g_new (Pixel, 1);
+ Pixel max_smoothed_curvature_pixel;
+ Pixel max_raw_curvature_pixel;
+ gfloat max_smoothed_curvature;
+ gfloat max_raw_curvature;
+
+ max_smoothed_curvature_pixel = gimp_vector2_new (-1.0, -1.0);
+ max_smoothed_curvature = 0.0f;
+
+ max_raw_curvature_pixel = gimp_vector2_new (x, y);
+ max_raw_curvature = curvatures[x + y * width];
+
+ p->x = x;
+ p->y = y;
+ g_queue_push_tail (q, p);
+ visited[x + y * width] = TRUE;
+
+ while (! g_queue_is_empty (q))
+ {
+ gfloat sc;
+ gfloat c;
+ gint p2x;
+ gint p2y;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ p = (Pixel *) g_queue_pop_head (q);
+ sc = smoothed_curvatures[(gint) p->x + (gint) p->y * width];
+ c = curvatures[(gint) p->x + (gint) p->y * width];
+
+ curvatures[(gint) p->x + (gint) p->y * width] = 0.0f;
+
+ p2x = (gint) p->x + 1;
+ p2y = (gint) p->y;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x - 1;
+ p2y = p->y;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x + 1;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x - 1;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x - 1;
+ p2y = p->y + 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ p2x = p->x + 1;
+ p2y = p->y - 1;
+ if (p2x >= 0 && p2x < width &&
+ p2y >= 0 && p2y < height &&
+ curvatures[p2x + p2y * width] > 0.0 &&
+ ! visited[p2x + p2y * width])
+ {
+ Pixel *p2 = g_new (Pixel, 1);
+
+ p2->x = p2x;
+ p2->y = p2y;
+ g_queue_push_tail (q, p2);
+ visited[p2x + p2y * width] = TRUE;
+ }
+
+ if (sc > max_smoothed_curvature)
+ {
+ max_smoothed_curvature_pixel = *p;
+ max_smoothed_curvature = sc;
+ }
+ if (c > max_raw_curvature)
+ {
+ max_raw_curvature_pixel = *p;
+ max_raw_curvature = c;
+ }
+ g_free (p);
+ }
+ if (max_smoothed_curvature > 0.0f)
+ {
+ curvatures[(gint) max_smoothed_curvature_pixel.x + (gint) max_smoothed_curvature_pixel.y * width] = max_smoothed_curvature;
+ g_array_append_val (max_positions, max_smoothed_curvature_pixel);
+ }
+ else
+ {
+ curvatures[(gint) max_raw_curvature_pixel.x + (gint) max_raw_curvature_pixel.y * width] = max_raw_curvature;
+ g_array_append_val (max_positions, max_raw_curvature_pixel);
+ }
+ }
+ }
+ }
+
+ end:
+ g_queue_free_full (q, g_free);
+ g_free (visited);
+
+ if (gimp_async_is_stopped (async))
+ {
+ g_array_free (max_positions, TRUE);
+ max_positions = NULL;
+ }
+
+ return max_positions;
+}
+
+static gint
+gimp_spline_candidate_cmp (const SplineCandidate *a,
+ const SplineCandidate *b,
+ gpointer user_data)
+{
+ /* This comparison actually returns the opposite of common comparison
+ * functions on purpose, as we want the first element on the list to
+ * be the "bigger".
+ */
+ if (a->quality < b->quality)
+ return 1;
+ else if (a->quality > b->quality)
+ return -1;
+ else
+ return 0;
+}
+
+static GList *
+gimp_lineart_find_spline_candidates (GArray *max_positions,
+ gfloat *normals,
+ gint width,
+ gint distance_threshold,
+ gfloat max_angle_deg,
+ GimpAsync *async)
+{
+ GList *candidates = NULL;
+ const float CosMin = cosf (M_PI * (max_angle_deg / 180.0));
+ gint i;
+
+ for (i = 0; i < max_positions->len; i++)
+ {
+ Pixel p1 = g_array_index (max_positions, Pixel, i);
+ gint j;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ g_list_free_full (candidates, g_free);
+
+ return NULL;
+ }
+
+ for (j = i + 1; j < max_positions->len; j++)
+ {
+ Pixel p2 = g_array_index (max_positions, Pixel, j);
+ const float distance = gimp_vector2_length_val (gimp_vector2_sub_val (p1, p2));
+
+ if (distance <= distance_threshold)
+ {
+ GimpVector2 normalP1;
+ GimpVector2 normalP2;
+ GimpVector2 p1f;
+ GimpVector2 p2f;
+ GimpVector2 p1p2;
+ float cosN;
+ float qualityA;
+ float qualityB;
+ float qualityC;
+ float quality;
+
+ normalP1 = gimp_vector2_new (normals[((gint) p1.x + (gint) p1.y * width) * 2],
+ normals[((gint) p1.x + (gint) p1.y * width) * 2 + 1]);
+ normalP2 = gimp_vector2_new (normals[((gint) p2.x + (gint) p2.y * width) * 2],
+ normals[((gint) p2.x + (gint) p2.y * width) * 2 + 1]);
+ p1f = gimp_vector2_new (p1.x, p1.y);
+ p2f = gimp_vector2_new (p2.x, p2.y);
+ p1p2 = gimp_vector2_sub_val (p2f, p1f);
+
+ cosN = gimp_vector2_inner_product_val (normalP1, (gimp_vector2_neg_val (normalP2)));
+ qualityA = MAX (0.0f, 1 - distance / distance_threshold);
+ qualityB = MAX (0.0f,
+ (float) (gimp_vector2_inner_product_val (normalP1, p1p2) - gimp_vector2_inner_product_val (normalP2, p1p2)) /
+ distance);
+ qualityC = MAX (0.0f, cosN - CosMin);
+ quality = qualityA * qualityB * qualityC;
+ if (quality > 0)
+ {
+ SplineCandidate *candidate = g_new (SplineCandidate, 1);
+
+ candidate->p1 = p1;
+ candidate->p2 = p2;
+ candidate->quality = quality;
+
+ candidates = g_list_insert_sorted_with_data (candidates, candidate,
+ (GCompareDataFunc) gimp_spline_candidate_cmp,
+ NULL);
+ }
+ }
+ }
+ }
+ return candidates;
+}
+
+static GArray *
+gimp_lineart_discrete_spline (Pixel p0,
+ GimpVector2 n0,
+ Pixel p1,
+ GimpVector2 n1)
+{
+ GArray *points = g_array_new (FALSE, TRUE, sizeof (Pixel));
+ const double a0 = 2 * p0.x - 2 * p1.x + n0.x - n1.x;
+ const double b0 = -3 * p0.x + 3 * p1.x - 2 * n0.x + n1.x;
+ const double c0 = n0.x;
+ const double d0 = p0.x;
+ const double a1 = 2 * p0.y - 2 * p1.y + n0.y - n1.y;
+ const double b1 = -3 * p0.y + 3 * p1.y - 2 * n0.y + n1.y;
+ const double c1 = n0.y;
+ const double d1 = p0.y;
+
+ double t = 0.0;
+ const double dtMin = 1.0 / MAX (fabs (p0.x - p1.x), fabs (p0.y - p1.y));
+ Pixel point = gimp_vector2_new ((gint) round (d0), (gint) round (d1));
+
+ g_array_append_val (points, point);
+
+ while (t <= 1.0)
+ {
+ const double t2 = t * t;
+ const double t3 = t * t2;
+ double dx;
+ double dy;
+ Pixel p = gimp_vector2_new ((gint) round (a0 * t3 + b0 * t2 + c0 * t + d0),
+ (gint) round (a1 * t3 + b1 * t2 + c1 * t + d1));
+
+ /* create gimp_vector2_neq () ? */
+ if (g_array_index (points, Pixel, points->len - 1).x != p.x ||
+ g_array_index (points, Pixel, points->len - 1).y != p.y)
+ {
+ g_array_append_val (points, p);
+ }
+ dx = fabs (3 * a0 * t * t + 2 * b0 * t + c0) + 1e-8;
+ dy = fabs (3 * a1 * t * t + 2 * b1 * t + c1) + 1e-8;
+ t += MIN (dtMin, 0.75 / MAX (dx, dy));
+ }
+ if (g_array_index (points, Pixel, points->len - 1).x != p1.x ||
+ g_array_index (points, Pixel, points->len - 1).y != p1.y)
+ {
+ g_array_append_val (points, p1);
+ }
+ return points;
+}
+
+static gint
+gimp_number_of_transitions (GArray *pixels,
+ GeglBuffer *buffer)
+{
+ int result = 0;
+
+ if (pixels->len > 0)
+ {
+ Pixel it = g_array_index (pixels, Pixel, 0);
+ guchar value;
+ gboolean previous;
+ gint i;
+
+ gegl_buffer_sample (buffer, (gint) it.x, (gint) it.y, NULL, &value, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ previous = (gboolean) value;
+
+ /* Starts at the second element. */
+ for (i = 1; i < pixels->len; i++)
+ {
+ it = g_array_index (pixels, Pixel, i);
+
+ gegl_buffer_sample (buffer, (gint) it.x, (gint) it.y, NULL, &value, NULL,
+ GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ result += ((gboolean) value != previous);
+ previous = (gboolean) value;
+ }
+ }
+
+ return result;
+}
+
+/**
+ * gimp_line_art_allow_closure:
+ * @mask: the current state of line art closure.
+ * @pixels: the pixels of a candidate closure (spline or segment).
+ * @fill_pixels: #GList of unsignificant pixels to bucket fill.
+ * @significant_size: number of pixels for area to be considered
+ * "significant".
+ * @minimum_size: number of pixels for area to be allowed.
+ *
+ * Checks whether adding the set of points @pixels to @mask will create
+ * 4-connected background regions whose size (i.e. number of pixels)
+ * will be below @minimum_size. If it creates such small areas, the
+ * function will refuse this candidate spline/segment, with the
+ * exception of very small areas under @significant_size. These
+ * micro-area are considered "unsignificant" and accepted (because they
+ * can be created in some conditions, for instance when created curves
+ * cross or start from a same endpoint), and one pixel for each
+ * micro-area will be added to @fill_pixels to be later filled along
+ * with the candidate pixels.
+ *
+ * Returns: #TRUE if @pixels should be added to @mask, #FALSE otherwise.
+ */
+static gboolean
+gimp_line_art_allow_closure (GeglBuffer *mask,
+ GArray *pixels,
+ GList **fill_pixels,
+ int significant_size,
+ int minimum_size)
+{
+ /* A theorem from the paper is that a zone with more than
+ * `2 * (@minimum_size - 1)` edgels (border pixels) will have more
+ * than @minimum_size pixels.
+ * Since we are following the edges of the area, we can therefore stop
+ * earlier if we reach this number of edgels.
+ */
+ const glong max_edgel_count = 2 * minimum_size;
+
+ Pixel *p = (Pixel*) pixels->data;
+ GList *fp = NULL;
+ gint i;
+
+ /* Mark pixels */
+ for (i = 0; i < pixels->len; i++)
+ {
+ if (p->x >= 0 && p->x < gegl_buffer_get_width (mask) &&
+ p->y >= 0 && p->y < gegl_buffer_get_height (mask))
+ {
+ guchar val;
+
+ gegl_buffer_sample (mask, (gint) p->x, (gint) p->y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ val = val ? 3 : 2;
+ gegl_buffer_set (mask, GEGL_RECTANGLE ((gint) p->x, (gint) p->y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ p++;
+ }
+
+ for (i = 0; i < pixels->len; i++)
+ {
+ Pixel p = g_array_index (pixels, Pixel, i);
+
+ for (int direction = 0; direction < 4; ++direction)
+ {
+ if (p.x >= 0 && p.x < gegl_buffer_get_width (mask) &&
+ p.y >= 0 && p.y < gegl_buffer_get_height (mask) &&
+ border_in_direction (mask, p, direction))
+ {
+ Edgel e;
+ guchar val;
+ glong count;
+ glong area;
+
+ gegl_buffer_sample (mask, (gint) p.x, (gint) p.y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if ((gboolean) (val & (4 << direction)))
+ continue;
+
+ gimp_edgel_init (&e);
+ e.x = p.x;
+ e.y = p.y;
+ e.direction = direction;
+
+ count = gimp_edgel_track_mark (mask, e, max_edgel_count);
+ if ((count != -1) && (count <= max_edgel_count))
+ {
+ area = gimp_edgel_region_area (mask, e);
+
+ if (area >= significant_size && area < minimum_size)
+ {
+ gint j;
+
+ /* Remove marks */
+ for (j = 0; j < pixels->len; j++)
+ {
+ Pixel p2 = g_array_index (pixels, Pixel, j);
+
+ if (p2.x >= 0 && p2.x < gegl_buffer_get_width (mask) &&
+ p2.y >= 0 && p2.y < gegl_buffer_get_height (mask))
+ {
+ guchar val;
+
+ gegl_buffer_sample (mask, (gint) p2.x, (gint) p2.y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ val &= 1;
+ gegl_buffer_set (mask, GEGL_RECTANGLE ((gint) p2.x, (gint) p2.y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ }
+ g_list_free_full (fp, g_free);
+
+ return FALSE;
+ }
+ else if (area > 0 && area < significant_size)
+ {
+ Pixel *np = g_new (Pixel, 1);
+
+ np->x = direction == XPlusDirection ? p.x + 1 : (direction == XMinusDirection ? p.x - 1 : p.x);
+ np->y = direction == YPlusDirection ? p.y + 1 : (direction == YMinusDirection ? p.y - 1 : p.y);
+
+ if (np->x >= 0 && np->x < gegl_buffer_get_width (mask) &&
+ np->y >= 0 && np->y < gegl_buffer_get_height (mask))
+ fp = g_list_prepend (fp, np);
+ else
+ g_free (np);
+ }
+ }
+ }
+ }
+ }
+
+ *fill_pixels = g_list_concat (*fill_pixels, fp);
+ /* Remove marks */
+ for (i = 0; i < pixels->len; i++)
+ {
+ Pixel p = g_array_index (pixels, Pixel, i);
+
+ if (p.x >= 0 && p.x < gegl_buffer_get_width (mask) &&
+ p.y >= 0 && p.y < gegl_buffer_get_height (mask))
+ {
+ guchar val;
+
+ gegl_buffer_sample (mask, (gint) p.x, (gint) p.y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ val &= 1;
+ gegl_buffer_set (mask, GEGL_RECTANGLE ((gint) p.x, (gint) p.y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ }
+ return TRUE;
+}
+
+static GArray *
+gimp_lineart_line_segment_until_hit (const GeglBuffer *mask,
+ Pixel start,
+ GimpVector2 direction,
+ int size)
+{
+ GeglBuffer *buffer = (GeglBuffer *) mask;
+ gboolean out = FALSE;
+ GArray *points = g_array_new (FALSE, TRUE, sizeof (Pixel));
+ int tmax;
+ GimpVector2 p0 = gimp_vector2_new (start.x, start.y);
+
+ gimp_vector2_mul (&direction, (gdouble) size);
+ direction.x = round (direction.x);
+ direction.y = round (direction.y);
+
+ tmax = MAX (abs ((int) direction.x), abs ((int) direction.y));
+
+ for (int t = 0; t <= tmax; ++t)
+ {
+ GimpVector2 v = gimp_vector2_add_val (p0, gimp_vector2_mul_val (direction, (float)t / tmax));
+ Pixel p;
+
+ p.x = (gint) round (v.x);
+ p.y = (gint) round (v.y);
+ if (p.x >= 0 && p.x < gegl_buffer_get_width (buffer) &&
+ p.y >= 0 && p.y < gegl_buffer_get_height (buffer))
+ {
+ guchar val;
+ gegl_buffer_sample (buffer, p.x, p.y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (out && val)
+ {
+ return points;
+ }
+ out = ! val;
+ }
+ else if (out)
+ {
+ return points;
+ }
+ else
+ {
+ g_array_free (points, TRUE);
+ return g_array_new (FALSE, TRUE, sizeof (Pixel));
+ }
+ g_array_append_val (points, p);
+ }
+
+ g_array_free (points, TRUE);
+ return g_array_new (FALSE, TRUE, sizeof (Pixel));
+}
+
+static gfloat *
+gimp_lineart_estimate_strokes_radii (GeglBuffer *mask,
+ GimpAsync *async)
+{
+ GeglBufferIterator *gi;
+ gfloat *dist;
+ gfloat *thickness;
+ GeglNode *graph;
+ GeglNode *input;
+ GeglNode *op;
+ gint width = gegl_buffer_get_width (mask);
+ gint height = gegl_buffer_get_height (mask);
+
+ /* Compute a distance map for the line art. */
+ dist = g_new (gfloat, width * height);
+
+ graph = gegl_node_new ();
+ input = gegl_node_new_child (graph,
+ "operation", "gegl:buffer-source",
+ "buffer", mask,
+ NULL);
+ op = gegl_node_new_child (graph,
+ "operation", "gegl:distance-transform",
+ "metric", GEGL_DISTANCE_METRIC_EUCLIDEAN,
+ "normalize", FALSE,
+ NULL);
+ gegl_node_connect_to (input, "output", op, "input");
+ gegl_node_blit (op, 1.0, gegl_buffer_get_extent (mask),
+ NULL, dist, GEGL_AUTO_ROWSTRIDE, GEGL_BLIT_DEFAULT);
+ g_object_unref (graph);
+
+ thickness = g_new0 (gfloat, width * height);
+ gi = gegl_buffer_iterator_new (mask, NULL, 0, NULL,
+ GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 1);
+ while (gegl_buffer_iterator_next (gi))
+ {
+ guint8 *m = (guint8*) gi->items[0].data;
+ gint startx = gi->items[0].roi.x;
+ gint starty = gi->items[0].roi.y;
+ gint endy = starty + gi->items[0].roi.height;
+ gint endx = startx + gi->items[0].roi.width;
+ gint x;
+ gint y;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gegl_buffer_iterator_stop (gi);
+
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ for (y = starty; y < endy; y++)
+ for (x = startx; x < endx; x++)
+ {
+ if (*m && dist[x + y * width] == 1.0)
+ {
+ gint dx = x;
+ gint dy = y;
+ gfloat d = 1.0;
+ gfloat nd;
+ gboolean neighbour_thicker = TRUE;
+
+ while (neighbour_thicker)
+ {
+ gint px = dx - 1;
+ gint py = dy - 1;
+ gint nx = dx + 1;
+ gint ny = dy + 1;
+
+ neighbour_thicker = FALSE;
+ if (px >= 0)
+ {
+ if ((nd = dist[px + dy * width]) > d)
+ {
+ d = nd;
+ dx = px;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ if (py >= 0 && (nd = dist[px + py * width]) > d)
+ {
+ d = nd;
+ dx = px;
+ dy = py;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ if (ny < height && (nd = dist[px + ny * width]) > d)
+ {
+ d = nd;
+ dx = px;
+ dy = ny;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ }
+ if (nx < width)
+ {
+ if ((nd = dist[nx + dy * width]) > d)
+ {
+ d = nd;
+ dx = nx;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ if (py >= 0 && (nd = dist[nx + py * width]) > d)
+ {
+ d = nd;
+ dx = nx;
+ dy = py;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ if (ny < height && (nd = dist[nx + ny * width]) > d)
+ {
+ d = nd;
+ dx = nx;
+ dy = ny;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ }
+ if (py > 0 && (nd = dist[dx + py * width]) > d)
+ {
+ d = nd;
+ dy = py;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ if (ny < height && (nd = dist[dx + ny * width]) > d)
+ {
+ d = nd;
+ dy = ny;
+ neighbour_thicker = TRUE;
+ continue;
+ }
+ }
+ thickness[(gint) x + (gint) y * width] = d;
+ }
+ m++;
+ }
+ }
+
+ end:
+ g_free (dist);
+
+ if (gimp_async_is_stopped (async))
+ g_clear_pointer (&thickness, g_free);
+
+ return thickness;
+}
+
+static void
+gimp_line_art_simple_fill (GeglBuffer *buffer,
+ gint x,
+ gint y,
+ gint *counter)
+{
+ guchar val;
+
+ if (x < 0 || x >= gegl_buffer_get_width (buffer) ||
+ y < 0 || y >= gegl_buffer_get_height (buffer) ||
+ *counter <= 0)
+ return;
+
+ gegl_buffer_sample (buffer, x, y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+
+ if (! val)
+ {
+ val = 1;
+ gegl_buffer_set (buffer, GEGL_RECTANGLE (x, y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ (*counter)--;
+ gimp_line_art_simple_fill (buffer, x + 1, y, counter);
+ gimp_line_art_simple_fill (buffer, x - 1, y, counter);
+ gimp_line_art_simple_fill (buffer, x, y + 1, counter);
+ gimp_line_art_simple_fill (buffer, x, y - 1, counter);
+ }
+}
+
+static guint
+visited_hash_fun (Pixel *key)
+{
+ /* Cantor pairing function. */
+ return (key->x + key->y) * (key->x + key->y + 1) / 2 + key->y;
+}
+
+static gboolean
+visited_equal_fun (Pixel *e1,
+ Pixel *e2)
+{
+ return (e1->x == e2->x && e1->y == e2->y);
+}
+
+static inline gboolean
+border_in_direction (GeglBuffer *mask,
+ Pixel p,
+ int direction)
+{
+ gint px = (gint) p.x + DeltaX[direction];
+ gint py = (gint) p.y + DeltaY[direction];
+
+ if (px >= 0 && px < gegl_buffer_get_width (mask) &&
+ py >= 0 && py < gegl_buffer_get_height (mask))
+ {
+ guchar val;
+
+ gegl_buffer_sample (mask, px, py, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ return ! ((gboolean) val);
+ }
+ return TRUE;
+}
+
+static inline GimpVector2
+pair2normal (Pixel p,
+ gfloat *normals,
+ gint width)
+{
+ return gimp_vector2_new (normals[((gint) p.x + (gint) p.y * width) * 2],
+ normals[((gint) p.x + (gint) p.y * width) * 2 + 1]);
+}
+/* Edgel functions */
+
+static Edgel *
+gimp_edgel_new (int x,
+ int y,
+ Direction direction)
+{
+ Edgel *edgel = g_new (Edgel, 1);
+
+ edgel->x = x;
+ edgel->y = y;
+ edgel->direction = direction;
+
+ gimp_edgel_init (edgel);
+
+ return edgel;
+}
+
+static void
+gimp_edgel_init (Edgel *edgel)
+{
+ edgel->x_normal = 0;
+ edgel->y_normal = 0;
+ edgel->curvature = 0;
+ edgel->next = edgel->previous = G_MAXUINT;
+}
+
+static void
+gimp_edgel_clear (Edgel **edgel)
+{
+ g_clear_pointer (edgel, g_free);
+}
+
+static int
+gimp_edgel_cmp (const Edgel* e1,
+ const Edgel* e2)
+{
+ gimp_assert (e1 && e2);
+
+ if ((e1->x == e2->x) && (e1->y == e2->y) &&
+ (e1->direction == e2->direction))
+ return 0;
+ else if ((e1->y < e2->y) || (e1->y == e2->y && e1->x < e2->x) ||
+ (e1->y == e2->y && e1->x == e2->x && e1->direction < e2->direction))
+ return -1;
+ else
+ return 1;
+}
+
+static guint
+edgel2index_hash_fun (Edgel *key)
+{
+ /* Cantor pairing function.
+ * Was not sure how to use the direction though. :-/
+ */
+ return (key->x + key->y) * (key->x + key->y + 1) / 2 + key->y * key->direction;
+}
+
+static gboolean
+edgel2index_equal_fun (Edgel *e1,
+ Edgel *e2)
+{
+ return (e1->x == e2->x && e1->y == e2->y &&
+ e1->direction == e2->direction);
+}
+
+/**
+ * @mask;
+ * @edgel:
+ * @size_limit:
+ *
+ * Track a border, marking inner pixels with a bit corresponding to the
+ * edgel traversed (4 << direction) for direction in {0,1,2,3}.
+ * Stop tracking after @size_limit edgels have been visited.
+ *
+ * Returns: Number of visited edgels, or -1 if an already visited edgel
+ * has been encountered.
+ */
+static glong
+gimp_edgel_track_mark (GeglBuffer *mask,
+ Edgel edgel,
+ long size_limit)
+{
+ Edgel start = edgel;
+ long count = 1;
+
+ do
+ {
+ guchar val;
+
+ gimp_edgelset_next8 (mask, &edgel, &edgel);
+ gegl_buffer_sample (mask, edgel.x, edgel.y, NULL, &val,
+ NULL, GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);
+ if (val & 2)
+ {
+ /* Only mark pixels of the spline/segment */
+ if (val & (4 << edgel.direction))
+ return -1;
+
+ /* Mark edgel in pixel (1 == In Mask, 2 == Spline/Segment) */
+ val |= (4 << edgel.direction);
+ gegl_buffer_set (mask, GEGL_RECTANGLE (edgel.x, edgel.y, 1, 1), 0,
+ NULL, &val, GEGL_AUTO_ROWSTRIDE);
+ }
+ if (gimp_edgel_cmp (&edgel, &start) != 0)
+ ++count;
+ }
+ while (gimp_edgel_cmp (&edgel, &start) != 0 && count <= size_limit);
+
+ return count;
+}
+
+/**
+ * gimp_edgel_region_area:
+ * @mask: current state of closed line art buffer.
+ * @start_edgel: edgel to follow.
+ *
+ * Follows a line border, starting from @start_edgel to compute the area
+ * enclosed by this border.
+ * Unfortunately this may return a negative area when the line does not
+ * close a zone. In this case, there is an uncertaincy on the size of
+ * the created zone, and we should consider it a big size.
+ *
+ * Returns: the area enclosed by the followed line, or a negative value
+ * if the zone is not closed (hence actual area unknown).
+ */
+static glong
+gimp_edgel_region_area (const GeglBuffer *mask,
+ Edgel start_edgel)
+{
+ Edgel edgel = start_edgel;
+ glong area = 0;
+
+ do
+ {
+ if (edgel.direction == XPlusDirection)
+ area -= edgel.x;
+ else if (edgel.direction == XMinusDirection)
+ area += edgel.x - 1;
+
+ gimp_edgelset_next8 (mask, &edgel, &edgel);
+ }
+ while (gimp_edgel_cmp (&edgel, &start_edgel) != 0);
+
+ return area;
+}
+
+/* Edgel sets */
+
+static GArray *
+gimp_edgelset_new (GeglBuffer *buffer,
+ GimpAsync *async)
+{
+ GeglBufferIterator *gi;
+ GArray *set;
+ GHashTable *edgel2index;
+ gint width = gegl_buffer_get_width (buffer);
+ gint height = gegl_buffer_get_height (buffer);
+
+ set = g_array_new (TRUE, TRUE, sizeof (Edgel *));
+ g_array_set_clear_func (set, (GDestroyNotify) gimp_edgel_clear);
+
+ if (width <= 1 || height <= 1)
+ return set;
+
+ edgel2index = g_hash_table_new ((GHashFunc) edgel2index_hash_fun,
+ (GEqualFunc) edgel2index_equal_fun);
+
+ gi = gegl_buffer_iterator_new (buffer, GEGL_RECTANGLE (0, 0, width, height),
+ 0, NULL, GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 5);
+ gegl_buffer_iterator_add (gi, buffer, GEGL_RECTANGLE (0, -1, width, height),
+ 0, NULL, GEGL_ACCESS_READ, GEGL_ABYSS_NONE);
+ gegl_buffer_iterator_add (gi, buffer, GEGL_RECTANGLE (0, 1, width, height),
+ 0, NULL, GEGL_ACCESS_READ, GEGL_ABYSS_NONE);
+ gegl_buffer_iterator_add (gi, buffer, GEGL_RECTANGLE (-1, 0, width, height),
+ 0, NULL, GEGL_ACCESS_READ, GEGL_ABYSS_NONE);
+ gegl_buffer_iterator_add (gi, buffer, GEGL_RECTANGLE (1, 0, width, height),
+ 0, NULL, GEGL_ACCESS_READ, GEGL_ABYSS_NONE);
+ while (gegl_buffer_iterator_next (gi))
+ {
+ guint8 *p = (guint8*) gi->items[0].data;
+ guint8 *prevy = (guint8*) gi->items[1].data;
+ guint8 *nexty = (guint8*) gi->items[2].data;
+ guint8 *prevx = (guint8*) gi->items[3].data;
+ guint8 *nextx = (guint8*) gi->items[4].data;
+ gint startx = gi->items[0].roi.x;
+ gint starty = gi->items[0].roi.y;
+ gint endy = starty + gi->items[0].roi.height;
+ gint endx = startx + gi->items[0].roi.width;
+ gint x;
+ gint y;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gegl_buffer_iterator_stop (gi);
+
+ gimp_async_abort (async);
+
+ goto end;
+ }
+
+ for (y = starty; y < endy; y++)
+ for (x = startx; x < endx; x++)
+ {
+ if (*(p++))
+ {
+ if (! *prevy)
+ gimp_edgelset_add (set, x, y, YMinusDirection, edgel2index);
+ if (! *nexty)
+ gimp_edgelset_add (set, x, y, YPlusDirection, edgel2index);
+ if (! *prevx)
+ gimp_edgelset_add (set, x, y, XMinusDirection, edgel2index);
+ if (! *nextx)
+ gimp_edgelset_add (set, x, y, XPlusDirection, edgel2index);
+ }
+ prevy++;
+ nexty++;
+ prevx++;
+ nextx++;
+ }
+ }
+
+ gimp_edgelset_build_graph (set, buffer, edgel2index, async);
+ if (gimp_async_is_stopped (async))
+ goto end;
+
+ gimp_edgelset_init_normals (set);
+
+ end:
+ g_hash_table_destroy (edgel2index);
+
+ if (gimp_async_is_stopped (async))
+ {
+ g_array_free (set, TRUE);
+ set = NULL;
+ }
+
+ return set;
+}
+
+static void
+gimp_edgelset_add (GArray *set,
+ int x,
+ int y,
+ Direction direction,
+ GHashTable *edgel2index)
+{
+ Edgel *edgel = gimp_edgel_new (x, y, direction);
+ unsigned long position = set->len;
+
+ g_array_append_val (set, edgel);
+ g_hash_table_insert (edgel2index, edgel, GUINT_TO_POINTER (position));
+}
+
+static void
+gimp_edgelset_init_normals (GArray *set)
+{
+ Edgel **e = (Edgel**) set->data;
+
+ while (*e)
+ {
+ GimpVector2 n = Direction2Normal[(*e)->direction];
+
+ (*e)->x_normal = n.x;
+ (*e)->y_normal = n.y;
+ e++;
+ }
+}
+
+static void
+gimp_edgelset_smooth_normals (GArray *set,
+ int mask_size,
+ GimpAsync *async)
+{
+ const gfloat sigma = mask_size * 0.775;
+ const gfloat den = 2 * sigma * sigma;
+ gfloat weights[65];
+ GimpVector2 smoothed_normal;
+ gint i;
+
+ gimp_assert (mask_size <= 65);
+
+ weights[0] = 1.0f;
+ for (int i = 1; i <= mask_size; ++i)
+ weights[i] = expf (-(i * i) / den);
+
+ for (i = 0; i < set->len; i++)
+ {
+ Edgel *it = g_array_index (set, Edgel*, i);
+ Edgel *edgel_before = g_array_index (set, Edgel*, it->previous);
+ Edgel *edgel_after = g_array_index (set, Edgel*, it->next);
+ int n = mask_size;
+ int i = 1;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ return;
+ }
+
+ smoothed_normal = Direction2Normal[it->direction];
+ while (n-- && (edgel_after != edgel_before))
+ {
+ smoothed_normal = gimp_vector2_add_val (smoothed_normal,
+ gimp_vector2_mul_val (Direction2Normal[edgel_before->direction], weights[i]));
+ smoothed_normal = gimp_vector2_add_val (smoothed_normal,
+ gimp_vector2_mul_val (Direction2Normal[edgel_after->direction], weights[i]));
+ edgel_before = g_array_index (set, Edgel *, edgel_before->previous);
+ edgel_after = g_array_index (set, Edgel *, edgel_after->next);
+ ++i;
+ }
+ gimp_vector2_normalize (&smoothed_normal);
+ it->x_normal = smoothed_normal.x;
+ it->y_normal = smoothed_normal.y;
+ }
+}
+
+static void
+gimp_edgelset_compute_curvature (GArray *set,
+ GimpAsync *async)
+{
+ gint i;
+
+ for (i = 0; i < set->len; i++)
+ {
+ Edgel *it = g_array_index (set, Edgel*, i);
+ Edgel *previous = g_array_index (set, Edgel *, it->previous);
+ Edgel *next = g_array_index (set, Edgel *, it->next);
+ GimpVector2 n_prev = gimp_vector2_new (previous->x_normal, previous->y_normal);
+ GimpVector2 n_next = gimp_vector2_new (next->x_normal, next->y_normal);
+ GimpVector2 diff = gimp_vector2_mul_val (gimp_vector2_sub_val (n_next, n_prev),
+ 0.5);
+ const float c = gimp_vector2_length_val (diff);
+ const float crossp = n_prev.x * n_next.y - n_prev.y * n_next.x;
+
+ it->curvature = (crossp > 0.0f) ? c : -c;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ return;
+ }
+ }
+}
+
+static void
+gimp_edgelset_build_graph (GArray *set,
+ GeglBuffer *buffer,
+ GHashTable *edgel2index,
+ GimpAsync *async)
+{
+ Edgel edgel;
+ gint i;
+
+ for (i = 0; i < set->len; i++)
+ {
+ Edgel *neighbor;
+ Edgel *it = g_array_index (set, Edgel *, i);
+ guint neighbor_pos;
+
+ if (gimp_async_is_canceled (async))
+ {
+ gimp_async_abort (async);
+
+ return;
+ }
+
+ gimp_edgelset_next8 (buffer, it, &edgel);
+
+ gimp_assert (g_hash_table_contains (edgel2index, &edgel));
+ neighbor_pos = GPOINTER_TO_UINT (g_hash_table_lookup (edgel2index, &edgel));
+ it->next = neighbor_pos;
+ neighbor = g_array_index (set, Edgel *, neighbor_pos);
+ neighbor->previous = i;
+ }
+}
+
+static void
+gimp_edgelset_next8 (const GeglBuffer *buffer,
+ Edgel *it,
+ Edgel *n)
+{
+ guint8 pixels[9];
+
+ n->x = it->x;
+ n->y = it->y;
+ n->direction = it->direction;
+
+ gegl_buffer_get ((GeglBuffer *) buffer,
+ GEGL_RECTANGLE (n->x - 1, n->y - 1, 3, 3),
+ 1.0, NULL, pixels, GEGL_AUTO_ROWSTRIDE,
+ GEGL_ABYSS_NONE);
+ switch (n->direction)
+ {
+ case XPlusDirection:
+ if (pixels[8])
+ {
+ ++(n->y);
+ ++(n->x);
+ n->direction = YMinusDirection;
+ }
+ else if (pixels[7])
+ {
+ ++(n->y);
+ }
+ else
+ {
+ n->direction = YPlusDirection;
+ }
+ break;
+ case YMinusDirection:
+ if (pixels[2])
+ {
+ ++(n->x);
+ --(n->y);
+ n->direction = XMinusDirection;
+ }
+ else if (pixels[5])
+ {
+ ++(n->x);
+ }
+ else
+ {
+ n->direction = XPlusDirection;
+ }
+ break;
+ case XMinusDirection:
+ if (pixels[0])
+ {
+ --(n->x);
+ --(n->y);
+ n->direction = YPlusDirection;
+ }
+ else if (pixels[1])
+ {
+ --(n->y);
+ }
+ else
+ {
+ n->direction = YMinusDirection;
+ }
+ break;
+ case YPlusDirection:
+ if (pixels[6])
+ {
+ --(n->x);
+ ++(n->y);
+ n->direction = XPlusDirection;
+ }
+ else if (pixels[3])
+ {
+ --(n->x);
+ }
+ else
+ {
+ n->direction = XMinusDirection;
+ }
+ break;
+ default:
+ g_return_if_reached ();
+ break;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-08 19:22:28 +0000