inkstitch/lib/utils/smoothing.py

61 wiersze
1.9 KiB
Python

import numpy as np
from ..stitches.running_stitch import stitch_curve_evenly
from .geometry import Point, coordinate_list_to_point_list
def _remove_duplicate_coordinates(coords_array):
"""Remove consecutive duplicate points from an array.
Arguments:
coords_array -- numpy.array
Returns:
a numpy.array of coordinates, minus consecutive duplicates
"""
differences = np.diff(coords_array, axis=0)
zero_differences = np.isclose(differences, 0)
keepers = np.r_[True, np.any(zero_differences == False, axis=1)] # noqa: E712
return coords_array[keepers]
def smooth_path(path, smoothness=1.0, iterations=5):
"""Smooth a path of coordinates.
Arguments:
path -- an iterable of coordinate tuples or Points
smoothness -- float, how much smoothing to apply. Bigger numbers
smooth more.
Returns:
A list of Points.
"""
points = coordinate_list_to_point_list(path)
if smoothness == 0:
return points
# Smoothing seems to look nicer if the line segments in the path are mostly
# similar in length. If we have some especially long segments, then the
# smoothed path sometimes diverges more from the original path as the
# spline curve struggles to fit the path. This can be especially bad at
# the start and end.
#
# Fortunately, we can convert the path to segments that are mostly the same
# length by using the running stitch algorithm.
points = stitch_curve_evenly(points, smoothness * 5, smoothness * 2)
points = np.array(points)
for _ in range(iterations):
ll = points.repeat(2, axis=0)
r = np.empty_like(ll)
if len(r) == 0:
continue
r[0] = ll[0]
r[2::2] = ll[1:-1:2]
r[1:-1:2] = ll[2::2]
r[-1] = ll[-1]
points = ll * 0.75 + r * 0.25
return [Point(*coord) for coord in points]