Traktor/myenv/Lib/site-packages/fontTools/varLib/interpolatableHelpers.py
2024-05-23 01:57:24 +02:00

381 lines
11 KiB
Python

from fontTools.ttLib.ttGlyphSet import LerpGlyphSet
from fontTools.pens.basePen import AbstractPen, BasePen, DecomposingPen
from fontTools.pens.pointPen import AbstractPointPen, SegmentToPointPen
from fontTools.pens.recordingPen import RecordingPen, DecomposingRecordingPen
from fontTools.misc.transform import Transform
from collections import defaultdict, deque
from math import sqrt, copysign, atan2, pi
from enum import Enum
import itertools
import logging
log = logging.getLogger("fontTools.varLib.interpolatable")
class InterpolatableProblem:
NOTHING = "nothing"
MISSING = "missing"
OPEN_PATH = "open_path"
PATH_COUNT = "path_count"
NODE_COUNT = "node_count"
NODE_INCOMPATIBILITY = "node_incompatibility"
CONTOUR_ORDER = "contour_order"
WRONG_START_POINT = "wrong_start_point"
KINK = "kink"
UNDERWEIGHT = "underweight"
OVERWEIGHT = "overweight"
severity = {
MISSING: 1,
OPEN_PATH: 2,
PATH_COUNT: 3,
NODE_COUNT: 4,
NODE_INCOMPATIBILITY: 5,
CONTOUR_ORDER: 6,
WRONG_START_POINT: 7,
KINK: 8,
UNDERWEIGHT: 9,
OVERWEIGHT: 10,
NOTHING: 11,
}
def sort_problems(problems):
"""Sort problems by severity, then by glyph name, then by problem message."""
return dict(
sorted(
problems.items(),
key=lambda _: -min(
(
(InterpolatableProblem.severity[p["type"]] + p.get("tolerance", 0))
for p in _[1]
),
),
reverse=True,
)
)
def rot_list(l, k):
"""Rotate list by k items forward. Ie. item at position 0 will be
at position k in returned list. Negative k is allowed."""
return l[-k:] + l[:-k]
class PerContourPen(BasePen):
def __init__(self, Pen, glyphset=None):
BasePen.__init__(self, glyphset)
self._glyphset = glyphset
self._Pen = Pen
self._pen = None
self.value = []
def _moveTo(self, p0):
self._newItem()
self._pen.moveTo(p0)
def _lineTo(self, p1):
self._pen.lineTo(p1)
def _qCurveToOne(self, p1, p2):
self._pen.qCurveTo(p1, p2)
def _curveToOne(self, p1, p2, p3):
self._pen.curveTo(p1, p2, p3)
def _closePath(self):
self._pen.closePath()
self._pen = None
def _endPath(self):
self._pen.endPath()
self._pen = None
def _newItem(self):
self._pen = pen = self._Pen()
self.value.append(pen)
class PerContourOrComponentPen(PerContourPen):
def addComponent(self, glyphName, transformation):
self._newItem()
self.value[-1].addComponent(glyphName, transformation)
class SimpleRecordingPointPen(AbstractPointPen):
def __init__(self):
self.value = []
def beginPath(self, identifier=None, **kwargs):
pass
def endPath(self) -> None:
pass
def addPoint(self, pt, segmentType=None):
self.value.append((pt, False if segmentType is None else True))
def vdiff_hypot2(v0, v1):
s = 0
for x0, x1 in zip(v0, v1):
d = x1 - x0
s += d * d
return s
def vdiff_hypot2_complex(v0, v1):
s = 0
for x0, x1 in zip(v0, v1):
d = x1 - x0
s += d.real * d.real + d.imag * d.imag
# This does the same but seems to be slower:
# s += (d * d.conjugate()).real
return s
def matching_cost(G, matching):
return sum(G[i][j] for i, j in enumerate(matching))
def min_cost_perfect_bipartite_matching_scipy(G):
n = len(G)
rows, cols = linear_sum_assignment(G)
assert (rows == list(range(n))).all()
return list(cols), matching_cost(G, cols)
def min_cost_perfect_bipartite_matching_munkres(G):
n = len(G)
cols = [None] * n
for row, col in Munkres().compute(G):
cols[row] = col
return cols, matching_cost(G, cols)
def min_cost_perfect_bipartite_matching_bruteforce(G):
n = len(G)
if n > 6:
raise Exception("Install Python module 'munkres' or 'scipy >= 0.17.0'")
# Otherwise just brute-force
permutations = itertools.permutations(range(n))
best = list(next(permutations))
best_cost = matching_cost(G, best)
for p in permutations:
cost = matching_cost(G, p)
if cost < best_cost:
best, best_cost = list(p), cost
return best, best_cost
try:
from scipy.optimize import linear_sum_assignment
min_cost_perfect_bipartite_matching = min_cost_perfect_bipartite_matching_scipy
except ImportError:
try:
from munkres import Munkres
min_cost_perfect_bipartite_matching = (
min_cost_perfect_bipartite_matching_munkres
)
except ImportError:
min_cost_perfect_bipartite_matching = (
min_cost_perfect_bipartite_matching_bruteforce
)
def contour_vector_from_stats(stats):
# Don't change the order of items here.
# It's okay to add to the end, but otherwise, other
# code depends on it. Search for "covariance".
size = sqrt(abs(stats.area))
return (
copysign((size), stats.area),
stats.meanX,
stats.meanY,
stats.stddevX * 2,
stats.stddevY * 2,
stats.correlation * size,
)
def matching_for_vectors(m0, m1):
n = len(m0)
identity_matching = list(range(n))
costs = [[vdiff_hypot2(v0, v1) for v1 in m1] for v0 in m0]
(
matching,
matching_cost,
) = min_cost_perfect_bipartite_matching(costs)
identity_cost = sum(costs[i][i] for i in range(n))
return matching, matching_cost, identity_cost
def points_characteristic_bits(points):
bits = 0
for pt, b in reversed(points):
bits = (bits << 1) | b
return bits
_NUM_ITEMS_PER_POINTS_COMPLEX_VECTOR = 4
def points_complex_vector(points):
vector = []
if not points:
return vector
points = [complex(*pt) for pt, _ in points]
n = len(points)
assert _NUM_ITEMS_PER_POINTS_COMPLEX_VECTOR == 4
points.extend(points[: _NUM_ITEMS_PER_POINTS_COMPLEX_VECTOR - 1])
while len(points) < _NUM_ITEMS_PER_POINTS_COMPLEX_VECTOR:
points.extend(points[: _NUM_ITEMS_PER_POINTS_COMPLEX_VECTOR - 1])
for i in range(n):
# The weights are magic numbers.
# The point itself
p0 = points[i]
vector.append(p0)
# The vector to the next point
p1 = points[i + 1]
d0 = p1 - p0
vector.append(d0 * 3)
# The turn vector
p2 = points[i + 2]
d1 = p2 - p1
vector.append(d1 - d0)
# The angle to the next point, as a cross product;
# Square root of, to match dimentionality of distance.
cross = d0.real * d1.imag - d0.imag * d1.real
cross = copysign(sqrt(abs(cross)), cross)
vector.append(cross * 4)
return vector
def add_isomorphisms(points, isomorphisms, reverse):
reference_bits = points_characteristic_bits(points)
n = len(points)
# if points[0][0] == points[-1][0]:
# abort
if reverse:
points = points[::-1]
bits = points_characteristic_bits(points)
else:
bits = reference_bits
vector = points_complex_vector(points)
assert len(vector) % n == 0
mult = len(vector) // n
mask = (1 << n) - 1
for i in range(n):
b = ((bits << (n - i)) & mask) | (bits >> i)
if b == reference_bits:
isomorphisms.append(
(rot_list(vector, -i * mult), n - 1 - i if reverse else i, reverse)
)
def find_parents_and_order(glyphsets, locations):
parents = [None] + list(range(len(glyphsets) - 1))
order = list(range(len(glyphsets)))
if locations:
# Order base master first
bases = (i for i, l in enumerate(locations) if all(v == 0 for v in l.values()))
if bases:
base = next(bases)
logging.info("Base master index %s, location %s", base, locations[base])
else:
base = 0
logging.warning("No base master location found")
# Form a minimum spanning tree of the locations
try:
from scipy.sparse.csgraph import minimum_spanning_tree
graph = [[0] * len(locations) for _ in range(len(locations))]
axes = set()
for l in locations:
axes.update(l.keys())
axes = sorted(axes)
vectors = [tuple(l.get(k, 0) for k in axes) for l in locations]
for i, j in itertools.combinations(range(len(locations)), 2):
graph[i][j] = vdiff_hypot2(vectors[i], vectors[j])
tree = minimum_spanning_tree(graph)
rows, cols = tree.nonzero()
graph = defaultdict(set)
for row, col in zip(rows, cols):
graph[row].add(col)
graph[col].add(row)
# Traverse graph from the base and assign parents
parents = [None] * len(locations)
order = []
visited = set()
queue = deque([base])
while queue:
i = queue.popleft()
visited.add(i)
order.append(i)
for j in sorted(graph[i]):
if j not in visited:
parents[j] = i
queue.append(j)
except ImportError:
pass
log.info("Parents: %s", parents)
log.info("Order: %s", order)
return parents, order
def transform_from_stats(stats, inverse=False):
# https://cookierobotics.com/007/
a = stats.varianceX
b = stats.covariance
c = stats.varianceY
delta = (((a - c) * 0.5) ** 2 + b * b) ** 0.5
lambda1 = (a + c) * 0.5 + delta # Major eigenvalue
lambda2 = (a + c) * 0.5 - delta # Minor eigenvalue
theta = atan2(lambda1 - a, b) if b != 0 else (pi * 0.5 if a < c else 0)
trans = Transform()
if lambda2 < 0:
# XXX This is a hack.
# The problem is that the covariance matrix is singular.
# This happens when the contour is a line, or a circle.
# In that case, the covariance matrix is not a good
# representation of the contour.
# We should probably detect this earlier and avoid
# computing the covariance matrix in the first place.
# But for now, we just avoid the division by zero.
lambda2 = 0
if inverse:
trans = trans.translate(-stats.meanX, -stats.meanY)
trans = trans.rotate(-theta)
trans = trans.scale(1 / sqrt(lambda1), 1 / sqrt(lambda2))
else:
trans = trans.scale(sqrt(lambda1), sqrt(lambda2))
trans = trans.rotate(theta)
trans = trans.translate(stats.meanX, stats.meanY)
return trans