# Authors: see git history # # Copyright (c) 2022 Authors # Licensed under the GNU GPL version 3.0 or later. See the file LICENSE for details. from inkex import Boolean, Group, PathElement, errormsg from inkex.units import convert_unit from shapely.geometry import LineString, MultiLineString, MultiPolygon, Polygon from shapely.ops import linemerge, split, voronoi_diagram from ..elements import FillStitch, Stroke from ..i18n import _ from ..stitches.running_stitch import running_stitch from ..svg import PIXELS_PER_MM, get_correction_transform from ..utils.geometry import line_string_to_point_list from .base import InkstitchExtension class FillToStroke(InkstitchExtension): def __init__(self, *args, **kwargs): InkstitchExtension.__init__(self, *args, **kwargs) self.arg_parser.add_argument("--options", dest="options", type=str, default="") self.arg_parser.add_argument("--info", dest="help", type=str, default="") self.arg_parser.add_argument("-t", "--threshold_mm", dest="threshold_mm", type=float, default=10) self.arg_parser.add_argument("-o", "--keep_original", dest="keep_original", type=Boolean, default=False) self.arg_parser.add_argument("-d", "--dashed_line", dest="dashed_line", type=Boolean, default=True) self.arg_parser.add_argument("-w", "--line_width_mm", dest="line_width_mm", type=float, default=1) def effect(self): if not self.svg.selected or not self.get_elements(): errormsg(_("Please select one or more fill objects to render the centerline.")) return cut_lines = [] fill_shapes = [] fill_shapes, cut_lines = self._get_shapes() if not fill_shapes: errormsg(_("Please select one or more fill objects to render the centerline.")) return # convert user input from mm to px self.threshold = self.options.threshold_mm * PIXELS_PER_MM self.line_width = self.options.line_width_mm * PIXELS_PER_MM # insert centerline group before the first selected element first = fill_shapes[0].node parent = first.getparent() index = parent.index(first) + 1 centerline_group = Group.new("Centerline Group", id=self.uniqueId("centerline_group_")) parent.insert(index, centerline_group) transform = get_correction_transform(first) for element in fill_shapes: transform = element.node.transform @ transform dashed = "stroke-dasharray:12,1.5;" if self.options.dashed_line else "" stroke_width = convert_unit(self.line_width, self.svg.unit) color = element.node.style('fill') style = "fill:none;stroke:%s;stroke-width:%s;%s" % (color, stroke_width, dashed) multipolygon = element.shape for cut_line in cut_lines: split_polygon = split(multipolygon, cut_line) poly = [polygon for polygon in split_polygon.geoms if isinstance(polygon, Polygon)] multipolygon = MultiPolygon(poly) for polygon in multipolygon.geoms: multilinestring = self._get_centerline(polygon) if multilinestring is None: continue # insert new elements self._insert_elements(multilinestring, centerline_group, index, transform, style) # clean up if not self.options.keep_original: self._remove_elements() def _get_shapes(self): fill_shapes = [] cut_lines = [] for element in self.elements: if isinstance(element, FillStitch): fill_shapes.append(element) elif isinstance(element, Stroke): cut_lines.extend(list(element.as_multi_line_string().geoms)) return fill_shapes, cut_lines def _remove_elements(self): for element in self.elements: # it is possible, that we get one element twice (if it has both, a fill and a stroke) # just ignore the second time try: element.node.getparent().remove(element.node) except AttributeError: pass def _get_high_res_polygon(self, polygon): # use running stitch method runs = [running_stitch(line_string_to_point_list(polygon.exterior), 1, 0.1)] if len(runs[0]) < 3: return for interior in polygon.interiors: runs.append(running_stitch(line_string_to_point_list(interior), 1, 0.1)) return MultiPolygon([(runs[0], runs[1:])]) def _get_centerline(self, polygon): # increase the resolution of the polygon polygon = self._get_high_res_polygon(polygon) if polygon is isinstance(polygon, MultiPolygon): return # generate voronoi centerline multilinestring = self._get_voronoi_centerline(polygon) if multilinestring is None: return # dead ends dead_ends = self._get_dead_end_lines(multilinestring) # avoid the splitting of line ends multilinestring = self._repair_splitted_ends(polygon, multilinestring, dead_ends) # update dead ends dead_ends = self._get_dead_end_lines(multilinestring) # filter small dead ends multilinestring = self._filter_short_dead_ends(multilinestring, dead_ends) if multilinestring is None: return # simplify polygon multilinestring = self._ensure_multilinestring(multilinestring.simplify(0.1)) if multilinestring is None: return return multilinestring def _get_voronoi_centerline(self, polygon): lines = voronoi_diagram(polygon, edges=True).geoms[0] if not isinstance(lines, MultiLineString): return multilinestring = [] for line in lines.geoms: if polygon.covers(line): multilinestring.append(line) lines = linemerge(multilinestring) if lines.is_empty: return return self._ensure_multilinestring(lines) def _get_start_and_end_points(self, multilinestring): points = [] for line in multilinestring.geoms: points.extend(line.coords[::len(line.coords)-1]) return points def _get_dead_end_lines(self, multilinestring): start_and_end_points = self._get_start_and_end_points(multilinestring) dead_ends = [] for line in multilinestring.geoms: num_neighbours_start = start_and_end_points.count(line.coords[0]) - 1 num_neighbours_end = start_and_end_points.count(line.coords[-1]) - 1 if num_neighbours_start == 0 or num_neighbours_end == 0: dead_ends.append(line) return dead_ends def _filter_short_dead_ends(self, multilinestring, dead_ends): lines = list(multilinestring.geoms) for i, line in enumerate(multilinestring.geoms): if line in dead_ends and line.length < self.threshold: lines.remove(line) lines = linemerge(lines) if lines.is_empty: lines = None else: lines = self._ensure_multilinestring(lines) return lines def _repair_splitted_ends(self, polygon, multilinestring, dead_ends): lines = list(multilinestring.geoms) for i, dead_end in enumerate(dead_ends): coords = dead_end.coords for j in range(i + 1, len(dead_ends)): common_point = set([coords[0], coords[-1]]).intersection(dead_ends[j].coords) if len(common_point) > 0: # prepare all lines to point to the common point dead_point1 = coords[0] if dead_point1 in common_point: dead_point1 = coords[-1] dead_point2 = dead_ends[j].coords[0] if dead_point2 in common_point: dead_point2 = dead_ends[j].coords[-1] end_line = LineString([dead_point1, dead_point2]) if polygon.covers(end_line): dead_end_center_point = end_line.centroid else: continue lines.append(LineString([dead_end_center_point, list(common_point)[0]])) if dead_end in lines: lines.remove(dead_end) if dead_ends[j] in lines: lines.remove(dead_ends[j]) continue return self._ensure_multilinestring(linemerge(lines)) def _ensure_multilinestring(self, lines): if not isinstance(lines, MultiLineString): lines = MultiLineString([lines]) return lines def _insert_elements(self, lines, parent, index, transform, style): for line in lines.geoms: d = "M " for coord in line.coords: d += "%s,%s " % (coord[0], coord[1]) centerline_element = PathElement(d=d, style=style, transform=str(transform)) parent.insert(index, centerline_element)