1 files changed, 184 insertions, 0 deletions
diff --git a/plug-ins/selection-to-path/curve.c b/plug-ins/selection-to-path/curve.c
new file mode 100644
index 0000000..afb157c
--- /dev/null
+++ b/plug-ins/selection-to-path/curve.c
@@ -0,0 +1,184 @@
+/* curve.c: operations on the lists of pixels and lists of curves.
+ *
+ * Copyright (C) 1992 Free Software Foundation, Inc.
+ *
+ * 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, 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 <glib.h>
+
+#include "global.h"
+#include "curve.h"
+
+
+/* Return an entirely empty curve.  */
+
+curve_type
+new_curve (void)
+{
+  curve_type curve = g_new (struct curve, 1);
+
+  curve->point_list = NULL;
+  CURVE_LENGTH (curve) = 0;
+  CURVE_CYCLIC (curve) = false;
+  CURVE_START_TANGENT (curve) = CURVE_END_TANGENT (curve) = NULL;
+  PREVIOUS_CURVE (curve) = NEXT_CURVE (curve) = NULL;
+
+  return curve;
+}
+
+
+/* Start the returned curve off with COORD as the first point.  */
+
+curve_type
+init_curve (coordinate_type coord)
+{
+  curve_type curve = new_curve ();
+
+  curve->point_list = g_new (point_type, 1);
+  CURVE_LENGTH (curve) = 1;
+
+  CURVE_POINT (curve, 0) = int_to_real_coord (coord);
+
+  return curve;
+}
+
+
+/* Don't copy the points or tangents, but copy everything else.  */
+
+curve_type
+copy_most_of_curve (curve_type old_curve)
+{
+  curve_type curve = new_curve ();
+
+  CURVE_CYCLIC (curve) = CURVE_CYCLIC (old_curve);
+  PREVIOUS_CURVE (curve) = PREVIOUS_CURVE (old_curve);
+  NEXT_CURVE (curve) = NEXT_CURVE (old_curve);
+
+  return curve;
+}
+
+
+/* The length of CURVE will be zero if we ended up not being able to fit
+   it (which in turn implies a problem elsewhere in the program, but at
+   any rate, we shouldn't try here to free the nonexistent curve).  */
+
+void
+free_curve (curve_type curve)
+{
+  if (CURVE_LENGTH (curve) > 0)
+    safe_free ((address *) &(curve->point_list));
+}
+
+
+void
+append_pixel (curve_type curve, coordinate_type coord)
+{
+  append_point (curve, int_to_real_coord (coord));
+}
+
+
+void
+append_point (curve_type curve, real_coordinate_type coord)
+{
+  CURVE_LENGTH (curve)++;
+  curve->point_list = g_realloc (curve->point_list,CURVE_LENGTH (curve) * sizeof(point_type));
+  LAST_CURVE_POINT (curve) = coord;
+  /* The t value does not need to be set.  */
+}
+
+/* Return an initialized but empty curve list.  */
+
+curve_list_type
+new_curve_list (void)
+{
+  curve_list_type curve_list;
+
+  curve_list.length    = 0;
+  curve_list.data      = NULL;
+  curve_list.clockwise = FALSE;
+
+  return curve_list;
+}
+
+
+/* Free a curve list and all the curves it contains.  */
+
+void
+free_curve_list (curve_list_type *curve_list)
+{
+  unsigned this_curve;
+
+  for (this_curve = 0; this_curve < curve_list->length; this_curve++)
+    free_curve (curve_list->data[this_curve]);
+
+  /* If the character was empty, it won't have any curves.  */
+  if (curve_list->data != NULL)
+    safe_free ((address *) &(curve_list->data));
+}
+
+
+/* Add an element to a curve list.  */
+
+void
+append_curve (curve_list_type *curve_list, curve_type curve)
+{
+  curve_list->length++;
+  curve_list->data = g_realloc (curve_list->data,curve_list->length*sizeof(curve_type));
+  curve_list->data[curve_list->length - 1] = curve;
+}
+
+
+/* Return an initialized but empty curve list array.  */
+
+curve_list_array_type
+new_curve_list_array (void)
+{
+  curve_list_array_type curve_list_array;
+
+  CURVE_LIST_ARRAY_LENGTH (curve_list_array) = 0;
+  curve_list_array.data = NULL;
+
+  return curve_list_array;
+}
+
+
+/* Free a curve list array and all the curve lists it contains.  */
+
+void
+free_curve_list_array (curve_list_array_type *curve_list_array)
+{
+  unsigned this_list;
+
+  for (this_list = 0; this_list < CURVE_LIST_ARRAY_LENGTH (*curve_list_array);
+       this_list++)
+    free_curve_list (&CURVE_LIST_ARRAY_ELT (*curve_list_array, this_list));
+
+  /* If the character was empty, it won't have any curves.  */
+  if (curve_list_array->data != NULL)
+    safe_free ((address *) &(curve_list_array->data));
+}
+
+
+/* Add an element to a curve list array.  */
+
+void
+append_curve_list (curve_list_array_type *l, curve_list_type curve_list)
+{
+  CURVE_LIST_ARRAY_LENGTH (*l)++;
+  l->data = g_realloc (l->data,( CURVE_LIST_ARRAY_LENGTH (*l))*sizeof(curve_list_type));
+  LAST_CURVE_LIST_ARRAY_ELT (*l) = curve_list;
+}