1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
"""Mitre Glyph:
mitreSize : Length of the segment created by the mitre. The default is 4.
maxAngle : Maximum angle in radians at which segments will be mitred. The default is .9 (about 50 degrees).
Works for both inside and outside angles
"""
import math
from robofab.objects.objectsRF import RPoint, RSegment
from fontbuild.convertCurves import replaceSegments
def getTangents(contours):
tmap = []
for c in contours:
clen = len(c)
for i in range(clen):
s = c[i]
p = s.points[-1]
ns = c[(i + 1) % clen]
ps = c[(clen + i - 1) % clen]
np = ns.points[1] if ns.type == 'curve' else ns.points[-1]
pp = s.points[2] if s.type == 'curve' else ps.points[-1]
tmap.append((pp - p, np - p))
return tmap
def normalizeVector(p):
m = getMagnitude(p);
if m != 0:
return p*(1/m)
else:
return RPoint(0,0)
def getMagnitude(p):
return math.sqrt(p.x*p.x + p.y*p.y)
def getDistance(v1,v2):
return getMagnitude(RPoint(v1.x - v2.x, v1.y - v2.y))
def getAngle(v1,v2):
angle = math.atan2(v1.y,v1.x) - math.atan2(v2.y,v2.x)
return (angle + (2*math.pi)) % (2*math.pi)
def angleDiff(a,b):
return math.pi - abs((abs(a - b) % (math.pi*2)) - math.pi)
def getAngle2(v1,v2):
return abs(angleDiff(math.atan2(v1.y, v1.x), math.atan2(v2.y, v2.x)))
def getMitreOffset(n,v1,v2,mitreSize=4,maxAngle=.9):
# dont mitre if segment is too short
if abs(getMagnitude(v1)) < mitreSize * 2 or abs(getMagnitude(v2)) < mitreSize * 2:
return
angle = getAngle2(v2,v1)
v1 = normalizeVector(v1)
v2 = normalizeVector(v2)
if v1.x == v2.x and v1.y == v2.y:
return
# only mitre corners sharper than maxAngle
if angle > maxAngle:
return
radius = mitreSize / abs(getDistance(v1,v2))
offset1 = RPoint(round(v1.x * radius), round(v1.y * radius))
offset2 = RPoint(round(v2.x * radius), round(v2.y * radius))
return offset1, offset2
def mitreGlyph(g,mitreSize,maxAngle):
if g == None:
return
tangents = getTangents(g.contours)
sid = -1
for c in g.contours:
segments = []
needsMitring = False
for s in c:
sid += 1
v1, v2 = tangents[sid]
off = getMitreOffset(s,v1,v2,mitreSize,maxAngle)
s1 = s.copy()
if off != None:
offset1, offset2 = off
p2 = s.points[-1] + offset2
s2 = RSegment('line', [(p2.x, p2.y)])
s1.points[0] += offset1
segments.append(s1)
segments.append(s2)
needsMitring = True
else:
segments.append(s1)
if needsMitring:
replaceSegments(c, segments)
|
