From cca66b9ec4e494c1d919bff0f71a820d8afab1fa Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:24:48 +0200 Subject: Adding upstream version 1.2.2. Signed-off-by: Daniel Baumann --- share/extensions/inkex/units.py | 150 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 share/extensions/inkex/units.py (limited to 'share/extensions/inkex/units.py') diff --git a/share/extensions/inkex/units.py b/share/extensions/inkex/units.py new file mode 100644 index 0000000..fec0e87 --- /dev/null +++ b/share/extensions/inkex/units.py @@ -0,0 +1,150 @@ +# -*- coding: utf-8 -*- +# +# Copyright (c) Aaron Spike +# Aurélio A. Heckert +# Bulia Byak +# Nicolas Dufour, nicoduf@yahoo.fr +# Peter J. R. Moulder +# Martin Owens +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. +# +""" +Convert to and from various units and find the closest matching unit. +""" + +import re + +# a dictionary of unit to user unit conversion factors +CONVERSIONS = { + "in": 96.0, + "pt": 1.3333333333333333, + "px": 1.0, + "mm": 3.779527559055118, + "cm": 37.79527559055118, + "m": 3779.527559055118, + "km": 3779527.559055118, + "Q": 0.94488188976378, + "pc": 16.0, + "yd": 3456.0, + "ft": 1152.0, + "": 1.0, # Default px +} + +# allowed unit types, including percentages, relative units, and others +# that are not suitable for direct conversion to a length. +# Note that this is _not_ an exhaustive list of allowed unit types. +UNITS = [ + "in", + "pt", + "px", + "mm", + "cm", + "m", + "km", + "Q", + "pc", + "yd", + "ft", + "", + "%", + "em", + "ex", + "ch", + "rem", + "vw", + "vh", + "vmin", + "vmax", + "deg", + "grad", + "rad", + "turn", + "s", + "ms", + "Hz", + "kHz", + "dpi", + "dpcm", + "dppx", +] + +UNIT_MATCH = re.compile(rf"({'|'.join(UNITS)})") +NUMBER_MATCH = re.compile(r"(([-+]?[0-9]+(\.[0-9]*)?|[-+]?\.[0-9]+)([eE][-+]?[0-9]+)?)") +BOTH_MATCH = re.compile(rf"^\s*{NUMBER_MATCH.pattern}\s*{UNIT_MATCH.pattern}\s*$") + + +def parse_unit(value, default_unit="px", default_value=None): + """ + Takes a value such as 55.32px and returns (55.32, 'px') + Returns default (None) if no match can be found + """ + ret = BOTH_MATCH.match(str(value)) + if ret: + return float(ret.groups()[0]), ret.groups()[-1] or default_unit + return (default_value, default_unit) if default_value is not None else None + + +def are_near_relative(point_a, point_b, eps=0.01): + """Return true if the points are near to eps""" + return (point_a - point_b <= point_a * eps) and ( + point_a - point_b >= -point_a * eps + ) + + +def discover_unit(value, viewbox, default="px"): + """Attempt to detect the unit being used based on the viewbox""" + # Default 100px when width can't be parsed + (value, unit) = parse_unit(value, default_value=100.0) + if unit not in CONVERSIONS: + return default + this_factor = CONVERSIONS[unit] * value / viewbox + + # try to find the svgunitfactor in the list of units known. If we don't find + # something, ... + for unit, unit_factor in CONVERSIONS.items(): + if unit != "": + # allow 1% error in factor + if are_near_relative(this_factor, unit_factor, eps=0.01): + return unit + return default + + +def convert_unit(value, to_unit, default="px"): + """Returns userunits given a string representation of units in another system + + Args: + value: string + to_unit: unit to convert to + default: if ``value`` contains no unit, what unit should be assumed. + + .. versionadded:: 1.1 + """ + value, from_unit = parse_unit(value, default_unit=default, default_value=0.0) + if from_unit in CONVERSIONS and to_unit in CONVERSIONS: + return ( + value * CONVERSIONS[from_unit] / CONVERSIONS.get(to_unit, CONVERSIONS["px"]) + ) + return 0.0 + + +def render_unit(value, unit): + """Checks and then renders a number with its unit""" + try: + if isinstance(value, str): + (value, unit) = parse_unit(value, default_unit=unit) + return f"{value:.6g}{ unit:s}" + except TypeError: + return "" -- cgit v1.2.3