from typing import Callable
from fontTools.pens.basePen import BasePen
[docs]
def pointToString(pt, ntos=str):
return " ".join(ntos(i) for i in pt)
[docs]
class SVGPathPen(BasePen):
"""Pen to draw SVG path d commands.
Example::
>>> pen = SVGPathPen(None)
>>> pen.moveTo((0, 0))
>>> pen.lineTo((1, 1))
>>> pen.curveTo((2, 2), (3, 3), (4, 4))
>>> pen.closePath()
>>> pen.getCommands()
'M0 0 1 1C2 2 3 3 4 4Z'
Args:
glyphSet: a dictionary of drawable glyph objects keyed by name
used to resolve component references in composite glyphs.
ntos: a callable that takes a number and returns a string, to
customize how numbers are formatted (default: str).
Note:
Fonts have a coordinate system where Y grows up, whereas in SVG,
Y grows down. As such, rendering path data from this pen in
SVG typically results in upside-down glyphs. You can fix this
by wrapping the data from this pen in an SVG group element with
transform, or wrap this pen in a transform pen. For example:
spen = svgPathPen.SVGPathPen(glyphset)
pen= TransformPen(spen , (1, 0, 0, -1, 0, 0))
glyphset[glyphname].draw(pen)
print(tpen.getCommands())
"""
def __init__(self, glyphSet, ntos: Callable[[float], str] = str):
BasePen.__init__(self, glyphSet)
self._commands = []
self._lastCommand = None
self._lastX = None
self._lastY = None
self._ntos = ntos
def _handleAnchor(self):
"""
>>> pen = SVGPathPen(None)
>>> pen.moveTo((0, 0))
>>> pen.moveTo((10, 10))
>>> pen._commands
['M10 10']
"""
if self._lastCommand == "M":
self._commands.pop(-1)
def _moveTo(self, pt):
"""
>>> pen = SVGPathPen(None)
>>> pen.moveTo((0, 0))
>>> pen._commands
['M0 0']
>>> pen = SVGPathPen(None)
>>> pen.moveTo((10, 0))
>>> pen._commands
['M10 0']
>>> pen = SVGPathPen(None)
>>> pen.moveTo((0, 10))
>>> pen._commands
['M0 10']
"""
self._handleAnchor()
t = "M%s" % (pointToString(pt, self._ntos))
self._commands.append(t)
self._lastCommand = "M"
self._lastX, self._lastY = pt
def _lineTo(self, pt):
"""
# duplicate point
>>> pen = SVGPathPen(None)
>>> pen.moveTo((10, 10))
>>> pen.lineTo((10, 10))
>>> pen._commands
['M10 10']
# vertical line
>>> pen = SVGPathPen(None)
>>> pen.moveTo((10, 10))
>>> pen.lineTo((10, 0))
>>> pen._commands
['M10 10', 'V0']
# horizontal line
>>> pen = SVGPathPen(None)
>>> pen.moveTo((10, 10))
>>> pen.lineTo((0, 10))
>>> pen._commands
['M10 10', 'H0']
# basic
>>> pen = SVGPathPen(None)
>>> pen.lineTo((70, 80))
>>> pen._commands
['L70 80']
# basic following a moveto
>>> pen = SVGPathPen(None)
>>> pen.moveTo((0, 0))
>>> pen.lineTo((10, 10))
>>> pen._commands
['M0 0', ' 10 10']
"""
x, y = pt
# duplicate point
if x == self._lastX and y == self._lastY:
return
# vertical line
elif x == self._lastX:
cmd = "V"
pts = self._ntos(y)
# horizontal line
elif y == self._lastY:
cmd = "H"
pts = self._ntos(x)
# previous was a moveto
elif self._lastCommand == "M":
cmd = None
pts = " " + pointToString(pt, self._ntos)
# basic
else:
cmd = "L"
pts = pointToString(pt, self._ntos)
# write the string
t = ""
if cmd:
t += cmd
self._lastCommand = cmd
t += pts
self._commands.append(t)
# store for future reference
self._lastX, self._lastY = pt
def _curveToOne(self, pt1, pt2, pt3):
"""
>>> pen = SVGPathPen(None)
>>> pen.curveTo((10, 20), (30, 40), (50, 60))
>>> pen._commands
['C10 20 30 40 50 60']
"""
t = "C"
t += pointToString(pt1, self._ntos) + " "
t += pointToString(pt2, self._ntos) + " "
t += pointToString(pt3, self._ntos)
self._commands.append(t)
self._lastCommand = "C"
self._lastX, self._lastY = pt3
def _qCurveToOne(self, pt1, pt2):
"""
>>> pen = SVGPathPen(None)
>>> pen.qCurveTo((10, 20), (30, 40))
>>> pen._commands
['Q10 20 30 40']
>>> from fontTools.misc.roundTools import otRound
>>> pen = SVGPathPen(None, ntos=lambda v: str(otRound(v)))
>>> pen.qCurveTo((3, 3), (7, 5), (11, 4))
>>> pen._commands
['Q3 3 5 4', 'Q7 5 11 4']
"""
assert pt2 is not None
t = "Q"
t += pointToString(pt1, self._ntos) + " "
t += pointToString(pt2, self._ntos)
self._commands.append(t)
self._lastCommand = "Q"
self._lastX, self._lastY = pt2
def _closePath(self):
"""
>>> pen = SVGPathPen(None)
>>> pen.closePath()
>>> pen._commands
['Z']
"""
self._commands.append("Z")
self._lastCommand = "Z"
self._lastX = self._lastY = None
def _endPath(self):
"""
>>> pen = SVGPathPen(None)
>>> pen.endPath()
>>> pen._commands
[]
"""
self._lastCommand = None
self._lastX = self._lastY = None
[docs]
def getCommands(self):
return "".join(self._commands)
[docs]
def main(args=None):
"""Generate per-character SVG from font and text"""
if args is None:
import sys
args = sys.argv[1:]
from fontTools.ttLib import TTFont
import argparse
parser = argparse.ArgumentParser(
"fonttools pens.svgPathPen", description="Generate SVG from text"
)
parser.add_argument("font", metavar="font.ttf", help="Font file.")
parser.add_argument("text", metavar="text", nargs="?", help="Text string.")
parser.add_argument(
"-y",
metavar="<number>",
help="Face index into a collection to open. Zero based.",
)
parser.add_argument(
"--glyphs",
metavar="whitespace-separated list of glyph names",
type=str,
help="Glyphs to show. Exclusive with text option",
)
parser.add_argument(
"--variations",
metavar="AXIS=LOC",
default="",
help="List of space separated locations. A location consist in "
"the name of a variation axis, followed by '=' and a number. E.g.: "
"wght=700 wdth=80. The default is the location of the base master.",
)
options = parser.parse_args(args)
fontNumber = int(options.y) if options.y is not None else 0
font = TTFont(options.font, fontNumber=fontNumber)
text = options.text
glyphs = options.glyphs
location = {}
for tag_v in options.variations.split():
fields = tag_v.split("=")
tag = fields[0].strip()
v = float(fields[1])
location[tag] = v
hhea = font["hhea"]
ascent, descent = hhea.ascent, hhea.descent
glyphset = font.getGlyphSet(location=location)
cmap = font["cmap"].getBestCmap()
if glyphs is not None and text is not None:
raise ValueError("Options --glyphs and --text are exclusive")
if glyphs is None:
glyphs = " ".join(cmap[ord(u)] for u in text)
glyphs = glyphs.split()
s = ""
width = 0
for g in glyphs:
glyph = glyphset[g]
pen = SVGPathPen(glyphset)
glyph.draw(pen)
commands = pen.getCommands()
s += '<g transform="translate(%d %d) scale(1 -1)"><path d="%s"/></g>\n' % (
width,
ascent,
commands,
)
width += glyph.width
print('<?xml version="1.0" encoding="UTF-8"?>')
print(
'<svg width="%d" height="%d" xmlns="http://www.w3.org/2000/svg">'
% (width, ascent - descent)
)
print(s, end="")
print("</svg>")
if __name__ == "__main__":
import sys
if len(sys.argv) == 1:
import doctest
sys.exit(doctest.testmod().failed)
sys.exit(main())