diff --git a/embroider.py b/embroider.py index ee9c4a249..5e0899b79 100644 --- a/embroider.py +++ b/embroider.py @@ -1225,6 +1225,39 @@ class SatinColumn(EmbroideryElement): @property @cache def flattened_beziers(self): + if len(self.csp) == 2: + return self.simple_flatten_beziers() + else: + return self.flatten_beziers_with_rungs() + + + def flatten_beziers_with_rungs(self): + input_paths = [self.flatten([path]) for path in self.csp] + input_paths = [shgeo.LineString(path[0]) for path in input_paths] + input_paths.sort(key=lambda path: path.length, reverse=True) + + # Imagine a satin column as a curvy ladder. + # The two long paths are the "rails" of the ladder. The remainder are + # the "rungs". + rails = input_paths[:2] + rungs = shgeo.MultiLineString(input_paths[2:]) + + result = [] + + for rail in rails: + # handle null intersections here? + linestrings = shapely.ops.split(rail, rungs) + + if len(linestrings.geoms) < len(rungs) + 1: + raise Exception("Expected %d linestrings, got %d" % (len(rungs) + 1, len(linestrings.geoms))) + + paths = [[PyEmb.Point(*coord) for coord in ls.coords] for ls in linestrings.geoms] + result.append(paths) + + return zip(*result) + + + def simple_flatten_beziers(self): # Given a pair of paths made up of bezier segments, flatten # each individual bezier segment into line segments that approximate # the curves. Retain the divisions between beziers -- we'll use those @@ -1256,14 +1289,12 @@ class SatinColumn(EmbroideryElement): node_id = self.node.get("id") - if len(self.csp) != 2: - self.fatal("satin column: object %s invalid: expected exactly two sub-paths, but there are %s" % (node_id, len(self.csp))) - if self.get_style("fill") is not None: self.fatal("satin column: object %s has a fill (but should not)" % node_id) - if len(self.csp[0]) != len(self.csp[1]): - self.fatal("satin column: object %s has two paths with an unequal number of points (%s and %s)" % (node_id, len(self.csp[0]), len(self.csp[1]))) + if len(self.csp) == 2: + if len(self.csp[0]) != len(self.csp[1]): + self.fatal("satin column: object %s has two paths with an unequal number of points (%s and %s)" % (node_id, len(self.csp[0]), len(self.csp[1]))) def offset_points(self, pos1, pos2, offset_px): # Expand or contract two points about their midpoint. This is diff --git a/images/satin_column_rungs_example.svg b/images/satin_column_rungs_example.svg new file mode 100644 index 000000000..0f629ecad --- /dev/null +++ b/images/satin_column_rungs_example.svg @@ -0,0 +1,107 @@ + + + + + + + + + + image/svg+xml + + + + + + + + + + + + + + + +