diff options
Diffstat (limited to 'lib/stitches')
| -rw-r--r-- | lib/stitches/__init__.py | 1 | ||||
| -rw-r--r-- | lib/stitches/auto_fill.py | 60 | ||||
| -rw-r--r-- | lib/stitches/contour_fill.py | 551 | ||||
| -rw-r--r-- | lib/stitches/fill.py | 7 | ||||
| -rw-r--r-- | lib/stitches/guided_fill.py | 183 | ||||
| -rw-r--r-- | lib/stitches/running_stitch.py | 96 |
6 files changed, 811 insertions, 87 deletions
diff --git a/lib/stitches/__init__.py b/lib/stitches/__init__.py index 4de88733..8b2738bc 100644 --- a/lib/stitches/__init__.py +++ b/lib/stitches/__init__.py @@ -5,6 +5,7 @@ from .auto_fill import auto_fill from .fill import legacy_fill +from .guided_fill import guided_fill from .running_stitch import * # Can't put this here because we get a circular import :( diff --git a/lib/stitches/auto_fill.py b/lib/stitches/auto_fill.py index 160d927e..65b1e06d 100644 --- a/lib/stitches/auto_fill.py +++ b/lib/stitches/auto_fill.py @@ -16,8 +16,7 @@ from shapely.strtree import STRtree from ..debug import debug from ..stitch_plan import Stitch from ..svg import PIXELS_PER_MM -from ..utils.geometry import Point as InkstitchPoint -from ..utils.geometry import line_string_to_point_list +from ..utils.geometry import Point as InkstitchPoint, line_string_to_point_list, ensure_multi_line_string from .fill import intersect_region_with_grating, stitch_row from .running_stitch import running_stitch @@ -59,9 +58,10 @@ def auto_fill(shape, starting_point, ending_point=None, underpath=True): - fill_stitch_graph = [] try: - fill_stitch_graph = build_fill_stitch_graph(shape, angle, row_spacing, end_row_spacing, starting_point, ending_point) + rows = intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing) + segments = [segment for row in rows for segment in row] + fill_stitch_graph = build_fill_stitch_graph(shape, segments, starting_point, ending_point) except ValueError: # Small shapes will cause the graph to fail - min() arg is an empty sequence through insert node return fallback(shape, running_stitch_length) @@ -88,9 +88,10 @@ def which_outline(shape, coords): # fail sometimes. point = shgeo.Point(*coords) - outlines = list(shape.boundary) + outlines = ensure_multi_line_string(shape.boundary).geoms outline_indices = list(range(len(outlines))) - closest = min(outline_indices, key=lambda index: outlines[index].distance(point)) + closest = min(outline_indices, + key=lambda index: outlines[index].distance(point)) return closest @@ -101,12 +102,12 @@ def project(shape, coords, outline_index): This returns the distance along the outline at which the point resides. """ - outline = list(shape.boundary)[outline_index] + outline = ensure_multi_line_string(shape.boundary).geoms[outline_index] return outline.project(shgeo.Point(*coords)) @debug.time -def build_fill_stitch_graph(shape, angle, row_spacing, end_row_spacing, starting_point=None, ending_point=None): +def build_fill_stitch_graph(shape, segments, starting_point=None, ending_point=None): """build a graph representation of the grating segments This function builds a specialized graph (as in graph theory) that will @@ -141,10 +142,6 @@ def build_fill_stitch_graph(shape, angle, row_spacing, end_row_spacing, starting debug.add_layer("auto-fill fill stitch") - # Convert the shape into a set of parallel line segments. - rows_of_segments = intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing) - segments = [segment for row in rows_of_segments for segment in row] - graph = networkx.MultiGraph() # First, add the grating segments as edges. We'll use the coordinates @@ -152,7 +149,7 @@ def build_fill_stitch_graph(shape, angle, row_spacing, end_row_spacing, starting for segment in segments: # networkx allows us to label nodes with arbitrary data. We'll # mark this one as a grating segment. - graph.add_edge(*segment, key="segment", underpath_edges=[]) + graph.add_edge(segment[0], segment[-1], key="segment", underpath_edges=[], geometry=shgeo.LineString(segment)) tag_nodes_with_outline_and_projection(graph, shape, graph.nodes()) add_edges_between_outline_nodes(graph, duplicate_every_other=True) @@ -174,7 +171,7 @@ def insert_node(graph, shape, point): point = tuple(point) outline = which_outline(shape, point) projection = project(shape, point, outline) - projected_point = list(shape.boundary)[outline].interpolate(projection) + projected_point = ensure_multi_line_string(shape.boundary).geoms[outline].interpolate(projection) node = (projected_point.x, projected_point.y) edges = [] @@ -199,7 +196,8 @@ def tag_nodes_with_outline_and_projection(graph, shape, nodes): def add_boundary_travel_nodes(graph, shape): - for outline_index, outline in enumerate(shape.boundary): + outlines = ensure_multi_line_string(shape.boundary).geoms + for outline_index, outline in enumerate(outlines): prev = None for point in outline.coords: point = shgeo.Point(point) @@ -230,7 +228,8 @@ def add_edges_between_outline_nodes(graph, duplicate_every_other=False): outline. """ - nodes = list(graph.nodes(data=True)) # returns a list of tuples: [(node, {data}), (node, {data}) ...] + # returns a list of tuples: [(node, {data}), (node, {data}) ...] + nodes = list(graph.nodes(data=True)) nodes.sort(key=lambda node: (node[1]['outline'], node[1]['projection'])) for outline_index, nodes in groupby(nodes, key=lambda node: node[1]['outline']): @@ -261,7 +260,10 @@ def fallback(shape, running_stitch_length): matter. """ - return running_stitch(line_string_to_point_list(shape.boundary[0]), running_stitch_length) + boundary = ensure_multi_line_string(shape.boundary) + outline = boundary.geoms[0] + + return running_stitch(line_string_to_point_list(outline), running_stitch_length) @debug.time @@ -325,7 +327,7 @@ def get_segments(graph): segments = [] for start, end, key, data in graph.edges(keys=True, data=True): if key == 'segment': - segments.append(shgeo.LineString((start, end))) + segments.append(data["geometry"]) return segments @@ -363,7 +365,8 @@ def process_travel_edges(graph, fill_stitch_graph, shape, travel_edges): # segments that _might_ intersect ls. Refining the result is # necessary but the STRTree still saves us a ton of time. if segment.crosses(ls): - start, end = segment.coords + start = segment.coords[0] + end = segment.coords[-1] fill_stitch_graph[start][end]['segment']['underpath_edges'].append(edge) # The weight of a travel edge is the length of the line segment. @@ -384,19 +387,10 @@ def process_travel_edges(graph, fill_stitch_graph, shape, travel_edges): def travel_grating(shape, angle, row_spacing): - rows_of_segments = intersect_region_with_grating(shape, angle, row_spacing) - segments = list(chain(*rows_of_segments)) - - return shgeo.MultiLineString(segments) + rows = intersect_region_with_grating(shape, angle, row_spacing) + segments = [segment for row in rows for segment in row] - -def ensure_multi_line_string(thing): - """Given either a MultiLineString or a single LineString, return a MultiLineString""" - - if isinstance(thing, shgeo.LineString): - return shgeo.MultiLineString([thing]) - else: - return thing + return shgeo.MultiLineString(list(segments)) def build_travel_edges(shape, fill_angle): @@ -443,7 +437,7 @@ def build_travel_edges(shape, fill_angle): debug.log_line_strings(grating3, "grating3") endpoints = [coord for mls in (grating1, grating2, grating3) - for ls in mls + for ls in mls.geoms for coord in ls.coords] diagonal_edges = ensure_multi_line_string(grating1.symmetric_difference(grating2)) @@ -451,7 +445,7 @@ def build_travel_edges(shape, fill_angle): # without this, floating point inaccuracies prevent the intersection points from lining up perfectly. vertical_edges = ensure_multi_line_string(snap(grating3.difference(grating1), diagonal_edges, 0.005)) - return endpoints, chain(diagonal_edges, vertical_edges) + return endpoints, chain(diagonal_edges.geoms, vertical_edges.geoms) def nearest_node(nodes, point, attr=None): diff --git a/lib/stitches/contour_fill.py b/lib/stitches/contour_fill.py new file mode 100644 index 00000000..c42cc6f2 --- /dev/null +++ b/lib/stitches/contour_fill.py @@ -0,0 +1,551 @@ +from collections import namedtuple +from itertools import chain + +import networkx as nx +import numpy as np +import trimesh +from shapely.geometry import GeometryCollection, MultiPolygon, Polygon, LineString, Point +from shapely.geometry.polygon import orient +from shapely.ops import nearest_points +from shapely.ops import polygonize + +from .running_stitch import running_stitch +from ..stitch_plan import Stitch +from ..utils import DotDict +from ..utils.geometry import cut, reverse_line_string, roll_linear_ring +from ..utils.geometry import ensure_geometry_collection, ensure_multi_polygon + + +class Tree(nx.DiGraph): + # This lets us do tree.nodes['somenode'].parent instead of the default + # tree.nodes['somenode']['parent']. + node_attr_dict_factory = DotDict + + def __init__(self, *args, **kwargs): + self.__node_num = 0 + super().__init__(**kwargs) + + def generate_node_name(self): + node = self.__node_num + self.__node_num += 1 + + return node + + +nearest_neighbor_tuple = namedtuple( + "nearest_neighbor_tuple", + [ + "nearest_point_parent", + "nearest_point_child", + "proj_distance_parent", + "child_node", + ], +) + + +def _offset_linear_ring(ring, offset, resolution, join_style, mitre_limit): + result = Polygon(ring).buffer(-offset, resolution, cap_style=2, join_style=join_style, mitre_limit=mitre_limit, single_sided=True) + result = ensure_multi_polygon(result) + rings = GeometryCollection([poly.exterior for poly in result.geoms]) + rings = rings.simplify(0.01, False) + + return _take_only_valid_linear_rings(rings) + + +def _take_only_valid_linear_rings(rings): + """ + Removes all geometries which do not form a "valid" LinearRing. + + A "valid" ring is one that does not form a straight line. + """ + + valid_rings = [] + + for ring in ensure_geometry_collection(rings).geoms: + if len(ring.coords) > 3 or (len(ring.coords) == 3 and ring.coords[0] != ring.coords[-1]): + valid_rings.append(ring) + + return GeometryCollection(valid_rings) + + +def _orient_linear_ring(ring, clockwise=True): + # Unfortunately for us, Inkscape SVGs have an inverted Y coordinate. + # Normally we don't have to care about that, but in this very specific + # case, the meaning of is_ccw is flipped. It actually tests whether + # a ring is clockwise. That makes this logic super-confusing. + if ring.is_ccw != clockwise: + return reverse_line_string(ring) + else: + return ring + + +def _orient_tree(tree, clockwise=True): + """ + Orient all linear rings in the tree. + + Since naturally holes have the opposite point ordering than non-holes we + make all lines within the tree uniform (having all the same ordering + direction) + """ + + for node in tree.nodes.values(): + node.val = _orient_linear_ring(node.val, clockwise) + + +def offset_polygon(polygon, offset, join_style, clockwise): + """ + Convert a polygon to a tree of isocontours. + + An isocontour is an offset version of the polygon's boundary. For example, + the isocontours of a circle are a set of concentric circles inside the + circle. + + This function takes a polygon (which may have holes) as input and creates + isocontours until the polygon is filled completely. The isocontours are + returned as a Tree, with a parent-child relationship indicating that the + parent isocontour contains the child isocontour. + + Arguments: + polygon - The shapely Polygon which may have holes + offset - The spacing between isocontours + join_style - Join style used when offsetting the Polygon border to create + isocontours. Can be round, mitered or bevel, as defined by + shapely: + https://shapely.readthedocs.io/en/stable/manual.html#shapely.geometry.JOIN_STYLE + clockwise - If True, isocontour points are in clockwise order; if False, counter-clockwise. + + Return Value: + Tree - see above + """ + + ordered_polygon = orient(polygon, -1) + tree = Tree() + tree.add_node('root', type='node', parent=None, val=ordered_polygon.exterior) + active_polygons = ['root'] + active_holes = [[]] + + for hole in ordered_polygon.interiors: + hole_node = tree.generate_node_name() + tree.add_node(hole_node, type="hole", val=hole) + active_holes[0].append(hole_node) + + while len(active_polygons) > 0: + current_poly = active_polygons.pop() + current_holes = active_holes.pop() + + outer, inners = _offset_polygon_and_holes(tree, current_poly, current_holes, offset, join_style) + polygons = _match_polygons_and_holes(outer, inners) + + for polygon in polygons.geoms: + new_polygon, new_holes = _convert_polygon_to_nodes(tree, polygon, parent_polygon=current_poly, child_holes=current_holes) + + if new_polygon is not None: + active_polygons.append(new_polygon) + active_holes.append(new_holes) + + for previous_hole in current_holes: + # If the previous holes are not + # contained in the new holes they + # have been merged with the + # outer polygon + if not tree.nodes[previous_hole].parent: + tree.nodes[previous_hole].parent = current_poly + tree.add_edge(current_poly, previous_hole) + + _orient_tree(tree, clockwise) + return tree + + +def _offset_polygon_and_holes(tree, poly, holes, offset, join_style): + outer = _offset_linear_ring( + tree.nodes[poly].val, + offset, + resolution=5, + join_style=join_style, + mitre_limit=10, + ) + + inners = [] + for hole in holes: + inner = _offset_linear_ring( + tree.nodes[hole].val, + -offset, # take negative offset for holes + resolution=5, + join_style=join_style, + mitre_limit=10, + ) + if not inner.is_empty: + inners.append(Polygon(inner.geoms[0])) + + return outer, inners + + +def _match_polygons_and_holes(outer, inners): + result = MultiPolygon(polygonize(outer.geoms)) + if len(inners) > 0: + result = ensure_geometry_collection(result.difference(MultiPolygon(inners))) + + return result + + +def _convert_polygon_to_nodes(tree, polygon, parent_polygon, child_holes): + polygon = orient(polygon, -1) + + if polygon.area < 0.1: + return None, None + + valid_rings = _take_only_valid_linear_rings(polygon.exterior) + + try: + exterior = valid_rings.geoms[0] + except IndexError: + return None, None + + node = tree.generate_node_name() + tree.add_node(node, type='node', parent=parent_polygon, val=exterior) + tree.add_edge(parent_polygon, node) + + hole_nodes = [] + for hole in polygon.interiors: + hole_node = tree.generate_node_name() + tree.add_node(hole_node, type="hole", val=hole) + for previous_hole in child_holes: + if Polygon(hole).contains(Polygon(tree.nodes[previous_hole].val)): + tree.nodes[previous_hole].parent = hole_node + tree.add_edge(hole_node, previous_hole) + hole_nodes.append(hole_node) + + return node, hole_nodes + + +def _get_nearest_points_closer_than_thresh(travel_line, next_line, threshold): + """ + Find the first point along travel_line that is within threshold of next_line. + + Input: + travel_line - The "parent" line for which the distance should + be minimized to enter next_line + next_line - contains the next_line which need to be entered + threshold - The distance between travel_line and next_line needs + to below threshold to be a valid point for entering + + Return value: + tuple or None + - the tuple structure is: + (point in travel_line, point in next_line) + - None is returned if there is no point that satisfies the threshold. + """ + + # We'll buffer next_line and find the intersection with travel_line. + # Then we'll return the very first point in the intersection, + # matched with a corresponding point on next_line. Fortunately for + # us, intersection of a Polygon with a LineString yields pieces of + # the LineString in the same order as the input LineString. + threshold_area = next_line.buffer(threshold) + portion_within_threshold = travel_line.intersection(threshold_area) + + if portion_within_threshold.is_empty: + return None + else: + # Projecting with 0 lets us avoid distinguishing between LineString and + # MultiLineString. + parent_point = Point(portion_within_threshold.interpolate(0)) + return nearest_points(parent_point, next_line) + + +def _create_nearest_points_list(travel_line, tree, children, threshold, threshold_hard): + """Determine the best place to enter each of parent's children + + Arguments: + travel_line - The "parent" line for which the distance should + be minimized to enter each child + children - children of travel_line that need to be entered + threshold - The distance between travel_line and a child should + to be below threshold to be a valid point for entering + threshold_hard - As a last resort, we can accept an entry point + that is this far way + + Return value: + list of nearest_neighbor_tuple - indicating where to enter each + respective child + """ + + children_nearest_points = [] + + for child in children: + result = _get_nearest_points_closer_than_thresh(travel_line, tree.nodes[child].val, threshold) + if result is None: + # where holes meet outer borders a distance + # up to 2 * used offset can arise + result = _get_nearest_points_closer_than_thresh(travel_line, tree.nodes[child].val, threshold_hard) + + proj = travel_line.project(result[0]) + children_nearest_points.append( + nearest_neighbor_tuple( + nearest_point_parent=result[0], + nearest_point_child=result[1], + proj_distance_parent=proj, + child_node=child, + ) + ) + + return children_nearest_points + + +def _find_path_inner_to_outer(tree, node, offset, starting_point, avoid_self_crossing, forward=True): + """Find a stitch path for this ring and its children. + + Strategy: A connection from parent to child is made as fast as possible to + reach the innermost child as fast as possible in order to stitch afterwards + from inner to outer. + + This function calls itself recursively to find a stitch path for each child + (and its children). + + Arguments: + tree - a Tree of isocontours (as returned by offset_polygon) + offset - offset that was passed to offset_polygon + starting_point - starting point for stitching + avoid_self_crossing - if True, tries to generate a path that does not + cross itself. + forward - if True, this ring will be stitched in its natural direction + (used internally by avoid_self_crossing) + + Return value: + LineString -- the stitching path + """ + + current_node = tree.nodes[node] + current_ring = current_node.val + + if not forward and avoid_self_crossing: + current_ring = reverse_line_string(current_ring) + + # reorder the coordinates of this ring so that it starts with + # a point nearest the starting_point + start_distance = current_ring.project(starting_point) + current_ring = roll_linear_ring(current_ring, start_distance) + current_node.val = current_ring + + # Find where along this ring to connect to each child. + nearest_points_list = _create_nearest_points_list( + current_ring, + tree, + tree[node], + threshold=1.5 * offset, + threshold_hard=2.05 * offset + ) + nearest_points_list.sort(key=lambda tup: tup.proj_distance_parent) + + result_coords = [] + if not nearest_points_list: + # We have no children, so we're at the center of a spiral. Reversing + # the innermost ring gives a nicer visual appearance. + if not avoid_self_crossing: + current_ring = reverse_line_string(current_ring) + else: + # This is a recursive algorithm. We'll stitch along this ring, pausing + # to jump to each child ring in turn and sew it before continuing on + # this ring. We'll end back where we started. + + result_coords.append(current_ring.coords[0]) + distance_so_far = 0 + for child_connection in nearest_points_list: + # Cut this ring into pieces before and after where this child will connect. + before, after = cut(current_ring, child_connection.proj_distance_parent - distance_so_far) + distance_so_far = child_connection.proj_distance_parent + + # Stitch the part leading up to this child. + if before is not None: + result_coords.extend(before.coords) + + # Stitch this child. The child will start and end in the same + # place, which should be close to our current location. + child_path = _find_path_inner_to_outer( + tree, + child_connection.child_node, + offset, + child_connection.nearest_point_child, + avoid_self_crossing, + not forward + ) + result_coords.extend(child_path.coords) + + # Skip ahead a little bit on this ring before resuming. This + # gives a nice spiral pattern, where we spiral out from the + # innermost child. + if after is not None: + skip, after = cut(after, offset) + distance_so_far += offset + + current_ring = after + + if current_ring is not None: + # skip a little at the end so we don't end exactly where we started. + remaining_length = current_ring.length + if remaining_length > offset: + current_ring, skip = cut(current_ring, current_ring.length - offset) + + result_coords.extend(current_ring.coords) + + return LineString(result_coords) + + +def inner_to_outer(tree, offset, stitch_length, starting_point, avoid_self_crossing): + """Fill a shape with spirals, from innermost to outermost.""" + + stitch_path = _find_path_inner_to_outer(tree, 'root', offset, starting_point, avoid_self_crossing) + points = [Stitch(*point) for point in stitch_path.coords] + stitches = running_stitch(points, stitch_length) + + return stitches + + +def _reorder_linear_ring(ring, start): + distances = ring - start + start_index = np.argmin(np.linalg.norm(distances, axis=1)) + return np.roll(ring, -start_index, axis=0) + + +def _interpolate_linear_rings(ring1, ring2, max_stitch_length, start=None): + """ + Interpolate between two LinearRings + + Creates a path from start_point on ring1 and around the rings, ending at a + nearby point on ring2. The path will smoothly transition from ring1 to + ring2 as it travels around the rings. + + Inspired by interpolate() from https://github.com/mikedh/pocketing/blob/master/pocketing/polygons.py + + Arguments: + ring1 -- LinearRing start point will lie on + ring2 -- LinearRing end point will lie on + max_stitch_length -- maximum stitch length (used to calculate resampling accuracy) + start -- Point on ring1 to start at, as a tuple + + Return value: Path interpolated between two LinearRings, as a LineString. + """ + + # Resample the two LinearRings so that they are the same number of points + # long. Then take the corresponding points in each ring and interpolate + # between them, gradually going more toward ring2. + # + # This is a little less accurate than the method in interpolate(), but several + # orders of magnitude faster because we're not building and querying a KDTree. + + num_points = int(20 * ring1.length / max_stitch_length) + ring1_resampled = trimesh.path.traversal.resample_path(np.array(ring1.coords), count=num_points) + ring2_resampled = trimesh.path.traversal.resample_path(np.array(ring2.coords), count=num_points) + + if start is not None: + ring1_resampled = _reorder_linear_ring(ring1_resampled, start) + ring2_resampled = _reorder_linear_ring(ring2_resampled, start) + + weights = np.linspace(0.0, 1.0, num_points).reshape((-1, 1)) + points = (ring1_resampled * (1.0 - weights)) + (ring2_resampled * weights) + result = LineString(points) + + return result.simplify(0.1, False) + + +def _check_and_prepare_tree_for_valid_spiral(tree): + """Check whether spiral fill is possible, and tweak if necessary. + + Takes a tree consisting of isocontours. If a parent has more than one child + we cannot create a spiral. However, to make the routine more robust, we + allow more than one child if only one of the children has own children. The + other children are removed in this routine then. If the routine returns true, + the tree will have been cleaned up from unwanted children. + + If even with these weaker constraints, a spiral is not possible, False is + returned. + """ + + def process_node(node): + children = set(tree[node]) + + if len(children) == 0: + return True + elif len(children) == 1: + child = children.pop() + return process_node(child) + else: + children_with_children = {child for child in children if tree[child]} + if len(children_with_children) > 1: + # Node has multiple children with children, so a perfect spiral is not possible. + # This False value will be returned all the way up the stack. + return False + elif len(children_with_children) == 1: + children_without_children = children - children_with_children + child = children_with_children.pop() + tree.remove_nodes_from(children_without_children) + return process_node(child) + else: + # None of the children has its own children, so we'll just take the longest. + longest = max(children, key=lambda child: tree[child]['val'].length) + shorter_children = children - {longest} + tree.remove_nodes_from(shorter_children) + return process_node(longest) + + return process_node('root') + + +def single_spiral(tree, stitch_length, starting_point): + """Fill a shape with a single spiral going from outside to center.""" + return _spiral_fill(tree, stitch_length, starting_point, _make_spiral) + + +def double_spiral(tree, stitch_length, starting_point): + """Fill a shape with a double spiral going from outside to center and back to outside. """ + return _spiral_fill(tree, stitch_length, starting_point, _make_fermat_spiral) + + +def _spiral_fill(tree, stitch_length, close_point, spiral_maker): + starting_point = close_point.coords[0] + + rings = _get_spiral_rings(tree) + path = spiral_maker(rings, stitch_length, starting_point) + path = [Stitch(*stitch) for stitch in path] + + return running_stitch(path, stitch_length) + + +def _get_spiral_rings(tree): + rings = [] + + node = 'root' + while True: + rings.append(tree.nodes[node].val) + + children = tree[node] + if len(children) == 0: + break + elif len(children) == 1: + node = list(children)[0] + else: + # We can only really fill a shape with a single spiral if each + # parent has only one child. We'll do our best though, because + # that is probably more helpful to the user than just refusing + # entirely. We'll pick the child that's closest to the center. + parent_center = rings[-1].centroid + node = min(children, key=lambda child: parent_center.distance(tree.nodes[child].val.centroid)) + + return rings + + +def _make_fermat_spiral(rings, stitch_length, starting_point): + forward = _make_spiral(rings[::2], stitch_length, starting_point) + back = _make_spiral(rings[1::2], stitch_length, starting_point) + back.reverse() + + return chain(forward, back) + + +def _make_spiral(rings, stitch_length, starting_point): + path = [] + + for ring1, ring2 in zip(rings[:-1], rings[1:]): + spiral_part = _interpolate_linear_rings(ring1, ring2, stitch_length, starting_point) + path.extend(spiral_part.coords) + + return path diff --git a/lib/stitches/fill.py b/lib/stitches/fill.py index 21e35d83..46352d4f 100644 --- a/lib/stitches/fill.py +++ b/lib/stitches/fill.py @@ -131,8 +131,6 @@ def intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing=Non # fill regions at the same angle and spacing always line up nicely. start -= (start + normal * center) % row_spacing - rows = [] - current_row_y = start while current_row_y < end: @@ -159,15 +157,13 @@ def intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing=Non runs.reverse() runs = [tuple(reversed(run)) for run in runs] - rows.append(runs) + yield runs if end_row_spacing: current_row_y += row_spacing + (end_row_spacing - row_spacing) * ((current_row_y - start) / height) else: current_row_y += row_spacing - return rows - def section_to_stitches(group_of_segments, angle, row_spacing, max_stitch_length, staggers, skip_last): stitches = [] @@ -221,6 +217,7 @@ def pull_runs(rows, shape, row_spacing): # print >>sys.stderr, "\n".join(str(len(row)) for row in rows) + rows = list(rows) runs = [] count = 0 while (len(rows) > 0): diff --git a/lib/stitches/guided_fill.py b/lib/stitches/guided_fill.py new file mode 100644 index 00000000..e4918e1d --- /dev/null +++ b/lib/stitches/guided_fill.py @@ -0,0 +1,183 @@ +from shapely import geometry as shgeo +from shapely.ops import linemerge, unary_union + +from .auto_fill import (build_fill_stitch_graph, + build_travel_graph, collapse_sequential_outline_edges, fallback, + find_stitch_path, graph_is_valid, travel) +from .running_stitch import running_stitch +from ..i18n import _ +from ..stitch_plan import Stitch +from ..utils.geometry import Point as InkstitchPoint, reverse_line_string + + +def guided_fill(shape, + guideline, + angle, + row_spacing, + max_stitch_length, + running_stitch_length, + skip_last, + starting_point, + ending_point=None, + underpath=True): + try: + segments = intersect_region_with_grating_guideline(shape, guideline, row_spacing) + fill_stitch_graph = build_fill_stitch_graph(shape, segments, starting_point, ending_point) + except ValueError: + # Small shapes will cause the graph to fail - min() arg is an empty sequence through insert node + return fallback(shape, running_stitch_length) + + if not graph_is_valid(fill_stitch_graph, shape, max_stitch_length): + return fallback(shape, running_stitch_length) + + travel_graph = build_travel_graph(fill_stitch_graph, shape, angle, underpath) + path = find_stitch_path(fill_stitch_graph, travel_graph, starting_point, ending_point) + result = path_to_stitches(path, travel_graph, fill_stitch_graph, max_stitch_length, running_stitch_length, skip_last) + + return result + + +def path_to_stitches(path, travel_graph, fill_stitch_graph, stitch_length, running_stitch_length, skip_last): + path = collapse_sequential_outline_edges(path) + + stitches = [] + + # If the very first stitch is travel, we'll omit it in travel(), so add it here. + if not path[0].is_segment(): + stitches.append(Stitch(*path[0].nodes[0])) + + for edge in path: + if edge.is_segment(): + current_edge = fill_stitch_graph[edge[0]][edge[-1]]['segment'] + path_geometry = current_edge['geometry'] + + if edge[0] != path_geometry.coords[0]: + path_geometry = reverse_line_string(path_geometry) + + point_list = [Stitch(*point) for point in path_geometry.coords] + new_stitches = running_stitch(point_list, stitch_length) + + # need to tag stitches + + if skip_last: + del new_stitches[-1] + + stitches.extend(new_stitches) + + travel_graph.remove_edges_from(fill_stitch_graph[edge[0]][edge[1]]['segment'].get('underpath_edges', [])) + else: + stitches.extend(travel(travel_graph, edge[0], edge[1], running_stitch_length, skip_last)) + + return stitches + + +def extend_line(line, minx, maxx, miny, maxy): + line = line.simplify(0.01, False) + + upper_left = InkstitchPoint(minx, miny) + lower_right = InkstitchPoint(maxx, maxy) + length = (upper_left - lower_right).length() + + point1 = InkstitchPoint(*line.coords[0]) + point2 = InkstitchPoint(*line.coords[1]) + new_starting_point = point1 - (point2 - point1).unit() * length + + point3 = InkstitchPoint(*line.coords[-2]) + point4 = InkstitchPoint(*line.coords[-1]) + new_ending_point = point4 + (point4 - point3).unit() * length + + return shgeo.LineString([new_starting_point.as_tuple()] + + line.coords[1:-1] + [new_ending_point.as_tuple()]) + + +def repair_multiple_parallel_offset_curves(multi_line): + lines = linemerge(multi_line) + lines = list(lines.geoms) + max_length = -1 + max_length_idx = -1 + for idx, subline in enumerate(lines): + if subline.length > max_length: + max_length = subline.length + max_length_idx = idx + # need simplify to avoid doubled points caused by linemerge + return lines[max_length_idx].simplify(0.01, False) + + +def repair_non_simple_lines(line): + repaired = unary_union(line) + counter = 0 + # Do several iterations since we might have several concatenated selfcrossings + while repaired.geom_type != 'LineString' and counter < 4: + line_segments = [] + for line_seg in repaired.geoms: + if not line_seg.is_ring: + line_segments.append(line_seg) + + repaired = unary_union(linemerge(line_segments)) + counter += 1 + if repaired.geom_type != 'LineString': + raise ValueError( + _("Guide line (or offset copy) is self crossing!")) + else: + return repaired + + +def intersect_region_with_grating_guideline(shape, line, row_spacing, flip=False): # noqa: C901 + + row_spacing = abs(row_spacing) + (minx, miny, maxx, maxy) = shape.bounds + upper_left = InkstitchPoint(minx, miny) + rows = [] + + if line.geom_type != 'LineString' or not line.is_simple: + line = repair_non_simple_lines(line) + # extend the line towards the ends to increase probability that all offsetted curves cross the shape + line = extend_line(line, minx, maxx, miny, maxy) + + line_offsetted = line + res = line_offsetted.intersection(shape) + while isinstance(res, (shgeo.GeometryCollection, shgeo.MultiLineString)) or (not res.is_empty and len(res.coords) > 1): + if isinstance(res, (shgeo.GeometryCollection, shgeo.MultiLineString)): + runs = [line_string.coords for line_string in res.geoms if ( + not line_string.is_empty and len(line_string.coords) > 1)] + else: + runs = [res.coords] + + runs.sort(key=lambda seg: ( + InkstitchPoint(*seg[0]) - upper_left).length()) + if flip: + runs.reverse() + runs = [tuple(reversed(run)) for run in runs] + + if row_spacing > 0: + rows.append(runs) + else: + rows.insert(0, runs) + + line_offsetted = line_offsetted.parallel_offset(row_spacing, 'left', 5) + if line_offsetted.geom_type == 'MultiLineString': # if we got multiple lines take the longest + line_offsetted = repair_multiple_parallel_offset_curves(line_offsetted) + if not line_offsetted.is_simple: + line_offsetted = repair_non_simple_lines(line_offsetted) + + if row_spacing < 0: + line_offsetted = reverse_line_string(line_offsetted) + line_offsetted = line_offsetted.simplify(0.01, False) + res = line_offsetted.intersection(shape) + if row_spacing > 0 and not isinstance(res, (shgeo.GeometryCollection, shgeo.MultiLineString)): + if (res.is_empty or len(res.coords) == 1): + row_spacing = -row_spacing + + line_offsetted = line.parallel_offset(row_spacing, 'left', 5) + if line_offsetted.geom_type == 'MultiLineString': # if we got multiple lines take the longest + line_offsetted = repair_multiple_parallel_offset_curves( + line_offsetted) + if not line_offsetted.is_simple: + line_offsetted = repair_non_simple_lines(line_offsetted) + # using negative row spacing leads as a side effect to reversed offsetted lines - here we undo this + line_offsetted = reverse_line_string(line_offsetted) + line_offsetted = line_offsetted.simplify(0.01, False) + res = line_offsetted.intersection(shape) + + for row in rows: + yield from row diff --git a/lib/stitches/running_stitch.py b/lib/stitches/running_stitch.py index 2878480c..cb8acf68 100644 --- a/lib/stitches/running_stitch.py +++ b/lib/stitches/running_stitch.py @@ -3,11 +3,15 @@ # Copyright (c) 2010 Authors # Licensed under the GNU GPL version 3.0 or later. See the file LICENSE for details. +from ..debug import debug +import math from copy import copy +from shapely.geometry import LineString """ Utility functions to produce running stitches. """ +@debug.time def running_stitch(points, stitch_length): """Generate running stitch along a path. @@ -23,56 +27,50 @@ def running_stitch(points, stitch_length): if len(points) < 2: return [] + # simplify will remove as many points as possible while ensuring that the + # resulting path stays within 0.75 pixels (0.2mm) of the original path. + path = LineString(points) + simplified = path.simplify(0.75, preserve_topology=False) + + # save the points that simplify picked and make sure we stitch them + important_points = set(simplified.coords) + important_point_indices = [i for i, point in enumerate(points) if point.as_tuple() in important_points] + output = [] - segment_start = points[0] - last_segment_direction = None - - # This tracks the distance we've traveled along the current segment so - # far. Each time we make a stitch, we add the stitch_length to this - # value. If we fall off the end of the current segment, we carry over - # the remainder to the next segment. - distance = 0.0 - - for segment_end in points[1:]: - segment = segment_end - segment_start - segment_length = segment.length() - - if segment_length == 0: - continue - - segment_direction = segment.unit() - - # corner detection - if last_segment_direction: - cos_angle_between = segment_direction * last_segment_direction - - # This checks whether the corner is sharper than 45 degrees. - if cos_angle_between < 0.5: - # Only add the corner point if it's more than 0.1mm away to - # avoid a double-stitch. - if (segment_start - output[-1]).length() > 0.1: - # add a stitch at the corner - output.append(segment_start) - - # next stitch needs to be stitch_length along this segment - distance = stitch_length - - while distance < segment_length: - output.append(segment_start + distance * segment_direction) - distance += stitch_length - - # prepare for the next segment - segment_start = segment_end - last_segment_direction = segment_direction - distance -= segment_length - - # stitch a single point if the path has a length of zero - if not output: - output.append(segment_start) - - # stitch the last point unless we're already almost there - if (segment_start - output[-1]).length() > 0.1 or len(output) == 0: - output.append(segment_start) + for start, end in zip(important_point_indices[:-1], important_point_indices[1:]): + # consider sections of the original path, each one starting and ending + # with an important point + section = points[start:end + 1] + output.append(section[0]) + + # Now split each section up evenly into stitches, each with a length no + # greater than the specified stitch_length. + section_ls = LineString(section) + section_length = section_ls.length + if section_length > stitch_length: + # a fractional stitch needs to be rounded up, which will make all + # of the stitches shorter + num_stitches = math.ceil(section_length / stitch_length) + actual_stitch_length = section_length / num_stitches + + distance = actual_stitch_length + + segment_start = section[0] + for segment_end in section[1:]: + segment = segment_end - segment_start + segment_length = segment.length() + + if distance < segment_length: + segment_direction = segment.unit() + + while distance < segment_length: + output.append(segment_start + distance * segment_direction) + distance += actual_stitch_length + + distance -= segment_length + segment_start = segment_end + + output.append(points[-1]) return output |