/* PIKA - Photo and Image Kooker Application * a rebranding of The GNU Image Manipulation Program (created with heckimp) * A derived work which may be trivial. However, any changes may be (C)2023 by Aldercone Studio * * Original copyright, applying to most contents (license remains unchanged): * 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 . */ #include "config.h" #include #include #include "libpikabase/pikabase.h" #include "libpikamath/pikamath.h" #include "core-types.h" #include "gegl/pika-gegl-loops.h" #include "gegl/pika-gegl-utils.h" #include "pika-parallel.h" #include "pika-priorities.h" #include "pika-utils.h" /* PIKA_TIMER */ #include "pikaasync.h" #include "pikacancelable.h" #include "pikadrawable.h" #include "pikaimage.h" #include "pikalineart.h" #include "pikapickable.h" #include "pikaprojection.h" #include "pikaviewable.h" #include "pikawaitable.h" #include "pika-intl.h" enum { COMPUTING_START, COMPUTING_END, LAST_SIGNAL, }; enum { PROP_0, PROP_SELECT_TRANSPARENT, PROP_MAX_GROW, PROP_THRESHOLD, PROP_AUTOMATIC_CLOSURE, PROP_SPLINE_MAX_LEN, PROP_SEGMENT_MAX_LEN, }; typedef struct _PikaLineArtPrivate PikaLineArtPrivate; struct _PikaLineArtPrivate { gboolean frozen; gboolean compute_after_thaw; PikaAsync *async; gint idle_id; PikaPickable *input; GeglBuffer *closed; gfloat *distmap; /* Used in the closing step. */ gboolean select_transparent; gdouble threshold; gboolean automatic_closure; 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; gboolean automatic_closure; 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 PikaVector2 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 PikaVector2 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 pika_line_art_finalize (GObject *object); static void pika_line_art_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec); static void pika_line_art_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec); /* Functions for asynchronous computation. */ static void pika_line_art_compute (PikaLineArt *line_art); static void pika_line_art_compute_cb (PikaAsync *async, PikaLineArt *line_art); static PikaAsync * pika_line_art_prepare_async (PikaLineArt *line_art, gint priority); static void pika_line_art_prepare_async_func (PikaAsync *async, LineArtData *data); static LineArtData * line_art_data_new (GeglBuffer *buffer, PikaLineArt *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 pika_line_art_idle (PikaLineArt *line_art); static void pika_line_art_input_invalidate_preview (PikaViewable *viewable, PikaLineArt *line_art); /* All actual computation functions. */ static GeglBuffer * pika_line_art_close (GeglBuffer *buffer, gboolean select_transparent, gdouble stroke_threshold, gboolean automatic_closure, 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, PikaAsync *async); static void pika_lineart_denoise (GeglBuffer *buffer, int size, PikaAsync *async); static void pika_lineart_compute_normals_curvatures (GeglBuffer *mask, gfloat *normals, gfloat *curvatures, gfloat *smoothed_curvatures, int normal_estimate_mask_size, PikaAsync *async); static gfloat * pika_lineart_get_smooth_curvatures (GArray *edgelset, PikaAsync *async); static GArray * pika_lineart_curvature_extremums (gfloat *curvatures, gfloat *smoothed_curvatures, gint curvatures_width, gint curvatures_height, PikaAsync *async); static gint pika_spline_candidate_cmp (const SplineCandidate *a, const SplineCandidate *b, gpointer user_data); static GList * pika_lineart_find_spline_candidates (GArray *max_positions, gfloat *normals, gint width, gint distance_threshold, gfloat max_angle_deg, PikaAsync *async); static GArray * pika_lineart_discrete_spline (Pixel p0, PikaVector2 n0, Pixel p1, PikaVector2 n1); static gint pika_number_of_transitions (GArray *pixels, GeglBuffer *buffer); static gboolean pika_line_art_allow_closure (GeglBuffer *mask, GArray *pixels, GList **fill_pixels, int significant_size, int minimum_size); static GArray * pika_lineart_line_segment_until_hit (const GeglBuffer *buffer, Pixel start, PikaVector2 direction, int size); static gfloat * pika_lineart_estimate_strokes_radii (GeglBuffer *mask, PikaAsync *async); static void pika_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 PikaVector2 pair2normal (Pixel p, gfloat *normals, gint width); /* Edgel */ static Edgel * pika_edgel_new (int x, int y, Direction direction); static void pika_edgel_init (Edgel *edgel); static void pika_edgel_clear (Edgel **edgel); static int pika_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 pika_edgel_track_mark (GeglBuffer *mask, Edgel edgel, long size_limit); static glong pika_edgel_region_area (const GeglBuffer *mask, Edgel start_edgel); /* Edgel set */ static GArray * pika_edgelset_new (GeglBuffer *buffer, PikaAsync *async); static void pika_edgelset_add (GArray *set, int x, int y, Direction direction, GHashTable *edgel2index); static void pika_edgelset_init_normals (GArray *set); static void pika_edgelset_smooth_normals (GArray *set, int mask_size, PikaAsync *async); static void pika_edgelset_compute_curvature (GArray *set, PikaAsync *async); static void pika_edgelset_build_graph (GArray *set, GeglBuffer *buffer, GHashTable *edgel2index, PikaAsync *async); static void pika_edgelset_next8 (const GeglBuffer *buffer, Edgel *it, Edgel *n); G_DEFINE_TYPE_WITH_CODE (PikaLineArt, pika_line_art, PIKA_TYPE_OBJECT, G_ADD_PRIVATE (PikaLineArt)) #define parent_class pika_line_art_parent_class static guint pika_line_art_signals[LAST_SIGNAL] = { 0 }; static void pika_line_art_class_init (PikaLineArtClass *klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); pika_line_art_signals[COMPUTING_START] = g_signal_new ("computing-start", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (PikaLineArtClass, computing_start), NULL, NULL, NULL, G_TYPE_NONE, 0); pika_line_art_signals[COMPUTING_END] = g_signal_new ("computing-end", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (PikaLineArtClass, computing_end), NULL, NULL, NULL, G_TYPE_NONE, 0); object_class->finalize = pika_line_art_finalize; object_class->set_property = pika_line_art_set_property; object_class->get_property = pika_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 | PIKA_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 | PIKA_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 | PIKA_PARAM_READWRITE)); g_object_class_install_property (object_class, PROP_AUTOMATIC_CLOSURE, g_param_spec_boolean ("automatic-closure", _("Whether or not we should perform the closing step"), _("Whether or not we should perform the closing step"), TRUE, G_PARAM_CONSTRUCT | PIKA_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 | PIKA_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 | PIKA_PARAM_READWRITE)); } static void pika_line_art_init (PikaLineArt *line_art) { line_art->priv = pika_line_art_get_instance_private (line_art); } static void pika_line_art_finalize (GObject *object) { PikaLineArt *line_art = PIKA_LINE_ART (object); line_art->priv->frozen = FALSE; pika_line_art_set_input (line_art, NULL); G_OBJECT_CLASS (parent_class)->finalize (object); } static void pika_line_art_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec) { PikaLineArt *line_art = PIKA_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); pika_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); pika_line_art_compute (line_art); } break; case PROP_AUTOMATIC_CLOSURE: if (line_art->priv->automatic_closure != g_value_get_boolean (value)) { line_art->priv->automatic_closure = g_value_get_boolean (value); pika_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; pika_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; pika_line_art_compute (line_art); } break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); break; } } static void pika_line_art_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec) { PikaLineArt *line_art = PIKA_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_AUTOMATIC_CLOSURE: g_value_set_boolean (value, line_art->priv->automatic_closure); 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 */ PikaLineArt * pika_line_art_new (void) { return g_object_new (PIKA_TYPE_LINE_ART, NULL); } void pika_line_art_bind_gap_length (PikaLineArt *line_art, gboolean bound) { line_art->priv->max_len_bound = bound; } void pika_line_art_set_input (PikaLineArt *line_art, PikaPickable *pickable) { g_return_if_fail (pickable == NULL || PIKA_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); pika_line_art_compute (line_art); if (pickable) { g_signal_connect (pickable, "invalidate-preview", G_CALLBACK (pika_line_art_input_invalidate_preview), line_art); } } } PikaPickable * pika_line_art_get_input (PikaLineArt *line_art) { return line_art->priv->input; } void pika_line_art_freeze (PikaLineArt *line_art) { g_return_if_fail (! line_art->priv->frozen); line_art->priv->frozen = TRUE; line_art->priv->compute_after_thaw = FALSE; } void pika_line_art_thaw (PikaLineArt *line_art) { g_return_if_fail (line_art->priv->frozen); line_art->priv->frozen = FALSE; if (line_art->priv->compute_after_thaw) { pika_line_art_compute (line_art); line_art->priv->compute_after_thaw = FALSE; } } gboolean pika_line_art_is_frozen (PikaLineArt *line_art) { return line_art->priv->frozen; } GeglBuffer * pika_line_art_get (PikaLineArt *line_art, gfloat **distmap) { g_return_val_if_fail (line_art->priv->input, NULL); if (line_art->priv->async) { pika_waitable_wait (PIKA_WAITABLE (line_art->priv->async)); } else if (! line_art->priv->closed) { pika_line_art_compute (line_art); if (line_art->priv->async) pika_waitable_wait (PIKA_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 pika_line_art_compute (PikaLineArt *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 pika_line_art_compute_cb() * bails if the async has been canceled, to avoid accessing the line art. */ g_signal_emit (line_art, pika_line_art_signals[COMPUTING_END], 0); pika_cancelable_cancel (PIKA_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) { /* pika_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 (pika_line_art_input_invalidate_preview), line_art); line_art->priv->async = pika_line_art_prepare_async (line_art, +1); g_signal_emit (line_art, pika_line_art_signals[COMPUTING_START], 0); g_signal_handlers_unblock_by_func ( line_art->priv->input, G_CALLBACK (pika_line_art_input_invalidate_preview), line_art); pika_async_add_callback_for_object (line_art->priv->async, (PikaAsyncCallback) pika_line_art_compute_cb, line_art, line_art); } } static void pika_line_art_compute_cb (PikaAsync *async, PikaLineArt *line_art) { if (pika_async_is_canceled (async)) return; if (pika_async_is_finished (async)) { LineArtResult *result; result = pika_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, pika_line_art_signals[COMPUTING_END], 0); } g_clear_object (&line_art->priv->async); } static PikaAsync * pika_line_art_prepare_async (PikaLineArt *line_art, gint priority) { GeglBuffer *buffer; PikaAsync *async; LineArtData *data; g_return_val_if_fail (PIKA_IS_PICKABLE (line_art->priv->input), NULL); pika_pickable_flush (line_art->priv->input); buffer = pika_gegl_buffer_dup ( pika_pickable_get_buffer (line_art->priv->input)); data = line_art_data_new (buffer, line_art); g_object_unref (buffer); async = pika_parallel_run_async_full ( priority, (PikaRunAsyncFunc) pika_line_art_prepare_async_func, data, (GDestroyNotify) line_art_data_free); return async; } static void pika_line_art_prepare_async_func (PikaAsync *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 (pika_async_is_canceled (async)) { gegl_buffer_iterator_stop (gi); pika_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. */ PIKA_TIMER_START(); closed = pika_line_art_close (buffer, select_transparent, data->threshold, data->automatic_closure, 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); PIKA_TIMER_END("close line-art"); if (buffer != data->buffer) g_object_unref (buffer); if (! pika_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; } pika_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, PikaLineArt *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->automatic_closure = line_art->priv->automatic_closure; 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 pika_line_art_idle (PikaLineArt *line_art) { line_art->priv->idle_id = 0; pika_line_art_compute (line_art); return G_SOURCE_REMOVE; } static void pika_line_art_input_invalidate_preview (PikaViewable *viewable, PikaLineArt *line_art) { if (! line_art->priv->idle_id) { line_art->priv->idle_id = g_idle_add_full ( PIKA_PRIORITY_VIEWABLE_IDLE, (GSourceFunc) pika_line_art_idle, line_art, NULL); } } /* All actual computation functions. */ /** * pika_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). * @automatic_closure: whether the closing step should be performed or * not. @spline_max_length and @segment_max_len are * used only if @automatic_closure is %TRUE. * @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 #PikaAsync 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 * pika_line_art_close (GeglBuffer *buffer, gboolean select_transparent, gdouble stroke_threshold, gboolean automatic_closure, 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, PikaAsync *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); pika_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 (pika_async_is_canceled (async)) { gegl_buffer_iterator_stop (gi); pika_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 (pika_async_is_canceled (async)) { gegl_buffer_iterator_stop (gi); pika_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) */ pika_lineart_denoise (strokes, minimal_lineart_area, async); if (pika_async_is_stopped (async)) goto end1; closed = g_object_ref (strokes); if (automatic_closure && (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 */ pika_lineart_compute_normals_curvatures (strokes, normals, curvatures, smoothed_curvatures, normal_estimate_mask_size, async); if (pika_async_is_stopped (async)) goto end2; radii = pika_lineart_estimate_strokes_radii (strokes, async); if (pika_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 (pika_async_is_canceled (async)) { pika_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 = pika_lineart_curvature_extremums (curvatures, smoothed_curvatures, width, height, async); if (pika_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 = pika_lineart_find_spline_candidates (keypoints, normals, width, spline_max_length, spline_max_angle, async); if (pika_async_is_stopped (async)) goto end3; g_object_unref (closed); closed = pika_gegl_buffer_dup (strokes); /* Draw splines */ while (candidates) { Pixel *p1; Pixel *p2; gboolean inserted = FALSE; if (pika_async_is_canceled (async)) { pika_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; PikaVector2 vect1 = pair2normal (*p1, normals, width); PikaVector2 vect2 = pair2normal (*p2, normals, width); gfloat distance = pika_vector2_length_val (pika_vector2_sub_val (*p1, *p2)); gint transitions; pika_vector2_mul (&vect1, distance); pika_vector2_mul (&vect1, spline_roundness); pika_vector2_mul (&vect2, distance); pika_vector2_mul (&vect2, spline_roundness); discrete_curve = pika_lineart_discrete_spline (*p1, vect1, *p2, vect2); transitions = allow_self_intersections ? pika_number_of_transitions (discrete_curve, strokes) : pika_number_of_transitions (discrete_curve, closed); if (transitions == 2 && pika_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 (pika_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 (pika_async_is_canceled (async)) { pika_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 = pika_lineart_line_segment_until_hit (closed, *point, pair2normal (*point, normals, width), segment_max_length); if (segment->len && pika_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 (pika_async_is_canceled (async)) { pika_async_abort (async); goto end2; } /* XXX A best approach would be to generalize * pika_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. */ pika_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 (pika_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_link (input, op); 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 (pika_async_is_stopped (async)) g_clear_object (&closed); return closed; } static void pika_lineart_denoise (GeglBuffer *buffer, int minimum_area, PikaAsync *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 (pika_async_is_canceled (async)) { pika_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 (pika_async_is_canceled (async)) { pika_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 pika_lineart_compute_normals_curvatures (GeglBuffer *mask, gfloat *normals, gfloat *curvatures, gfloat *smoothed_curvatures, int normal_estimate_mask_size, PikaAsync *async) { gfloat *edgels_curvatures = NULL; gfloat *smoothed_curvature; GArray *es = NULL; Edgel **e; gint width = gegl_buffer_get_width (mask); es = pika_edgelset_new (mask, async); if (pika_async_is_stopped (async)) goto end; e = (Edgel **) es->data; pika_edgelset_smooth_normals (es, normal_estimate_mask_size, async); if (pika_async_is_stopped (async)) goto end; pika_edgelset_compute_curvature (es, async); if (pika_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 (pika_async_is_canceled (async)) { pika_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 (pika_async_is_canceled (async)) { pika_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 = pika_lineart_get_smooth_curvatures (es, async); if (pika_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 * pika_lineart_get_smooth_curvatures (GArray *edgelset, PikaAsync *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 (pika_async_is_canceled (async)) { pika_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 * pika_lineart_curvature_extremums (gfloat *curvatures, gfloat *smoothed_curvatures, gint width, gint height, PikaAsync *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 (pika_async_is_canceled (async)) { pika_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 = pika_vector2_new (-1.0, -1.0); max_smoothed_curvature = 0.0f; max_raw_curvature_pixel = pika_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 (pika_async_is_canceled (async)) { pika_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 (pika_async_is_stopped (async)) { g_array_free (max_positions, TRUE); max_positions = NULL; } return max_positions; } static gint pika_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 * pika_lineart_find_spline_candidates (GArray *max_positions, gfloat *normals, gint width, gint distance_threshold, gfloat max_angle_deg, PikaAsync *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 (pika_async_is_canceled (async)) { pika_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 = pika_vector2_length_val (pika_vector2_sub_val (p1, p2)); if (distance <= distance_threshold) { PikaVector2 normalP1; PikaVector2 normalP2; PikaVector2 p1f; PikaVector2 p2f; PikaVector2 p1p2; float cosN; float qualityA; float qualityB; float qualityC; float quality; normalP1 = pika_vector2_new (normals[((gint) p1.x + (gint) p1.y * width) * 2], normals[((gint) p1.x + (gint) p1.y * width) * 2 + 1]); normalP2 = pika_vector2_new (normals[((gint) p2.x + (gint) p2.y * width) * 2], normals[((gint) p2.x + (gint) p2.y * width) * 2 + 1]); p1f = pika_vector2_new (p1.x, p1.y); p2f = pika_vector2_new (p2.x, p2.y); p1p2 = pika_vector2_sub_val (p2f, p1f); cosN = pika_vector2_inner_product_val (normalP1, (pika_vector2_neg_val (normalP2))); qualityA = MAX (0.0f, 1 - distance / distance_threshold); qualityB = MAX (0.0f, (float) (pika_vector2_inner_product_val (normalP1, p1p2) - pika_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) pika_spline_candidate_cmp, NULL); } } } } return candidates; } static GArray * pika_lineart_discrete_spline (Pixel p0, PikaVector2 n0, Pixel p1, PikaVector2 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 = pika_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 = pika_vector2_new ((gint) round (a0 * t3 + b0 * t2 + c0 * t + d0), (gint) round (a1 * t3 + b1 * t2 + c1 * t + d1)); /* create pika_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 pika_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; } /** * pika_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 insignificant 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 "insignificant" 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 pika_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; pika_edgel_init (&e); e.x = p.x; e.y = p.y; e.direction = direction; count = pika_edgel_track_mark (mask, e, max_edgel_count); if ((count != -1) && (count <= max_edgel_count)) { area = pika_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 * pika_lineart_line_segment_until_hit (const GeglBuffer *mask, Pixel start, PikaVector2 direction, int size) { GeglBuffer *buffer = (GeglBuffer *) mask; gboolean out = FALSE; GArray *points = g_array_new (FALSE, TRUE, sizeof (Pixel)); int tmax; PikaVector2 p0 = pika_vector2_new (start.x, start.y); pika_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) { PikaVector2 v = pika_vector2_add_val (p0, pika_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 * pika_lineart_estimate_strokes_radii (GeglBuffer *mask, PikaAsync *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_link (input, op); 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 (pika_async_is_canceled (async)) { gegl_buffer_iterator_stop (gi); pika_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 (pika_async_is_stopped (async)) g_clear_pointer (&thickness, g_free); return thickness; } static void pika_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)--; pika_line_art_simple_fill (buffer, x + 1, y, counter); pika_line_art_simple_fill (buffer, x - 1, y, counter); pika_line_art_simple_fill (buffer, x, y + 1, counter); pika_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 PikaVector2 pair2normal (Pixel p, gfloat *normals, gint width) { return pika_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 * pika_edgel_new (int x, int y, Direction direction) { Edgel *edgel = g_new (Edgel, 1); edgel->x = x; edgel->y = y; edgel->direction = direction; pika_edgel_init (edgel); return edgel; } static void pika_edgel_init (Edgel *edgel) { edgel->x_normal = 0; edgel->y_normal = 0; edgel->curvature = 0; edgel->next = edgel->previous = G_MAXUINT; } static void pika_edgel_clear (Edgel **edgel) { g_clear_pointer (edgel, g_free); } static int pika_edgel_cmp (const Edgel* e1, const Edgel* e2) { pika_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 pika_edgel_track_mark (GeglBuffer *mask, Edgel edgel, long size_limit) { Edgel start = edgel; long count = 1; do { guchar val; pika_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 (pika_edgel_cmp (&edgel, &start) != 0) ++count; } while (pika_edgel_cmp (&edgel, &start) != 0 && count <= size_limit); return count; } /** * pika_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 uncertainty 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 pika_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; pika_edgelset_next8 (mask, &edgel, &edgel); } while (pika_edgel_cmp (&edgel, &start_edgel) != 0); return area; } /* Edgel sets */ static GArray * pika_edgelset_new (GeglBuffer *buffer, PikaAsync *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) pika_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 (pika_async_is_canceled (async)) { gegl_buffer_iterator_stop (gi); pika_async_abort (async); goto end; } for (y = starty; y < endy; y++) for (x = startx; x < endx; x++) { if (*(p++)) { if (! *prevy) pika_edgelset_add (set, x, y, YMinusDirection, edgel2index); if (! *nexty) pika_edgelset_add (set, x, y, YPlusDirection, edgel2index); if (! *prevx) pika_edgelset_add (set, x, y, XMinusDirection, edgel2index); if (! *nextx) pika_edgelset_add (set, x, y, XPlusDirection, edgel2index); } prevy++; nexty++; prevx++; nextx++; } } pika_edgelset_build_graph (set, buffer, edgel2index, async); if (pika_async_is_stopped (async)) goto end; pika_edgelset_init_normals (set); end: g_hash_table_destroy (edgel2index); if (pika_async_is_stopped (async)) { g_array_free (set, TRUE); set = NULL; } return set; } static void pika_edgelset_add (GArray *set, int x, int y, Direction direction, GHashTable *edgel2index) { Edgel *edgel = pika_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 pika_edgelset_init_normals (GArray *set) { Edgel **e = (Edgel**) set->data; while (*e) { PikaVector2 n = Direction2Normal[(*e)->direction]; (*e)->x_normal = n.x; (*e)->y_normal = n.y; e++; } } static void pika_edgelset_smooth_normals (GArray *set, int mask_size, PikaAsync *async) { const gfloat sigma = mask_size * 0.775; const gfloat den = 2 * sigma * sigma; gfloat weights[65]; PikaVector2 smoothed_normal; gint i; pika_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 (pika_async_is_canceled (async)) { pika_async_abort (async); return; } smoothed_normal = Direction2Normal[it->direction]; while (n-- && (edgel_after != edgel_before)) { smoothed_normal = pika_vector2_add_val (smoothed_normal, pika_vector2_mul_val (Direction2Normal[edgel_before->direction], weights[i])); smoothed_normal = pika_vector2_add_val (smoothed_normal, pika_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; } pika_vector2_normalize (&smoothed_normal); it->x_normal = smoothed_normal.x; it->y_normal = smoothed_normal.y; } } static void pika_edgelset_compute_curvature (GArray *set, PikaAsync *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); PikaVector2 n_prev = pika_vector2_new (previous->x_normal, previous->y_normal); PikaVector2 n_next = pika_vector2_new (next->x_normal, next->y_normal); PikaVector2 diff = pika_vector2_mul_val (pika_vector2_sub_val (n_next, n_prev), 0.5); const float c = pika_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 (pika_async_is_canceled (async)) { pika_async_abort (async); return; } } } static void pika_edgelset_build_graph (GArray *set, GeglBuffer *buffer, GHashTable *edgel2index, PikaAsync *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 (pika_async_is_canceled (async)) { pika_async_abort (async); return; } pika_edgelset_next8 (buffer, it, &edgel); pika_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 pika_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; } }