mightyscape-1.2/extensions/fablabchemnitz/living_hinge/living_hinge.py

266 lines
8.8 KiB
Python

#!/usr/bin/env python3
"""
hinge_cuts.py
A module for creating lines to laser cut living hinges
Copyright (C) 2013 Mark Endicott; drphonon@gmail.com
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.
For a copy of the GNU General Public License
write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""
"""
Change in version 0.2.
Changed self.unittouu to self.svg.unittouu
and self.uutounit to self.uutounit
to make it work with Inkscape 0.91
Thanks to Pete Prodoehl for pointing this out.
"""
"""
Change in version 0.3
Add a direction option so the cuts can be done in the X or Y direction.
Modification by Sylvain GARNAVAULT; garnav@wanadoo.fr
"""
"""
Change in version 0.4.
Python3 / inkscape 1.0 migration
"""
__version__ = "0.4"
import inkex
import gettext
_ = gettext.gettext
from lxml import etree
from inkex import Rectangle
class LivingHinge(inkex.EffectExtension):
def add_arguments(self, pars):
pars.add_argument('--direction',default='y',help='cuts direction')
pars.add_argument('--unit',default='mm',help='units of measurement')
pars.add_argument('--cut_length',type=float, default=0,help='length of the cuts for the hinge.')
pars.add_argument('--gap_length',type=float, default=0,help='separation distance between successive hinge cuts.')
pars.add_argument('--sep_distance',type=float, default=0,help='distance between successive lines of hinge cuts.')
def effect(self):
unit=self.options.unit
# which direction are we cutting
dir = self.options.direction
# starting cut length. Will be adjusted for get an integer number of cuts in the y-direction.
l = self.svg.unittouu(str(self.options.cut_length) + unit)
# cut separation in the y-direction
d = self.svg.unittouu(str(self.options.gap_length) + unit)
# starting separation between lines of cuts in the x-direction. Will be adjusted to get an integer
# number of cut lines in the x-direction.
dd = self.svg.unittouu(str(self.options.sep_distance) + unit)
# get selected nodes
if self.svg.selected:
# put lines on the current layer
for id, element in self.svg.selection.filter(Rectangle).items():
# inkex.utils.debug("id:" + id)
# for key in node.attrib.keys():
# inkex.utils.debug(key + ": " + element.get(key))
bbox = element.bounding_box()
# calculate the cut lines for the hinge
if (dir=="y"):
lines, l_actual, d_actual, dd_actual = self.calcYCutLines(bbox.left, bbox.top, bbox.width, bbox.height, l, d, dd)
else:
lines, l_actual, d_actual, dd_actual = self.calcXCutLines(bbox.left, bbox.top, bbox.width, bbox.height, l, d, dd)
s = ''
for line in lines:
s = s + "M %s, %s L %s, %s " % (line['x1'], line['y1'], line['x2'], line['y2'])
style = { 'stroke': '#000000', 'fill': 'none', 'stroke-width': self.svg.unittouu("0.1 mm")}
drw = {'style':str(inkex.Style(style)), 'd': s}
hinge = etree.SubElement(element.getparent(), inkex.addNS('path', 'svg'), drw)
desc = etree.SubElement(hinge, inkex.addNS('desc', 'svg'))
desc.text = "Hinge cut parameters: actual(requested)\n" \
"cut length: %.2f %s (%.2f %s)\n" \
"gap length: %.2f %s (%.2f %s)\n" \
"separation distance: %.2f %s (%.2f %s)" % (self.svg.uutounit(l_actual, unit), unit, self.svg.uutounit(l, unit), unit,
self.svg.uutounit(d_actual, unit), unit, self.svg.uutounit(d, unit), unit,
self.svg.uutounit(dd_actual, unit), unit, self.svg.uutounit(dd, unit), unit)
else:
inkex.utils.debug("No rectangle(s) have been selected.")
def calcYCutLines(self, x, y, dx, dy, l, d, dd):
"""
Return a list of cut lines as dicts. Each dict contains the end points for one cut line.
[{x1, y1, x2, y2}, ... ]
Parameters
x, y: the coordinates of the lower left corner of the bounding rect
dx, dy: width and height of the bounding rect
l: the nominal length of a cut line
d: the separation between cut lines in the y-direction
dd: the nominal separation between cut lines in the x-direction
l will be adjusted so that there is an integral number of cuts in the y-direction.
dd will be adjusted so that there is an integral number of cuts in the x-direction.
"""
ret = []
# use l as a starting guess. Adjust it so that we get an integer number of cuts in the y-direction
# First compute the number of cuts in the y-direction using l. This will not in general be an integer.
p = (dy-d)/(d+l)
#round p to the nearest integer
p = round(p)
#compute the new l that will result in p cuts in the y-direction.
if p == 0:
p = 1 #avoid divison by zero
l = (dy-d)/p - d
# use dd as a starting guess. Adjust it so that we get an even integer number of cut lines in the x-direction.
p = dx/dd
p = round(p)
if p % 2 == 1:
p = p + 1
dd = dx/p
#
# Column A cuts
#
currx = 0
donex = False
while not donex:
doney = False
starty = 0
endy = (l + d)/2.0
while not doney:
if endy >= dy:
endy = dy
# Add the end points of the line
ret.append({'x1' : x + currx, 'y1' : y + starty, 'x2': x + currx, 'y2': y + endy})
starty = endy + d
endy = starty + l
if starty >= dy:
doney = True
currx = currx + dd * 2.0
if currx - dx > dd:
donex = True
# inkex.utils.debug("lastx: " + str(lastx) + "; currx: " + str(currx))
#
#Column B cuts
#
currx = dd
donex = False
while not donex:
doney = False
starty = d
endy = starty + l
while not doney:
if endy >= dy:
endy = dy
# create a line
ret.append({'x1' : x + currx, 'y1' : y + starty, 'x2': x + currx, 'y2': y + endy})
starty = endy + d
endy = starty + l
if starty >= dy:
doney = True
currx = currx + dd*2.0
if currx > dx:
donex = True
return (ret, l, d, dd)
def calcXCutLines(self, x, y, dx, dy, l, d, dd):
"""
Return a list of cut lines as dicts. Each dict contains the end points for one cut line.
[{x1, y1, x2, y2}, ... ]
Parameters
x, y: the coordinates of the lower left corner of the bounding rect
dx, dy: width and height of the bounding rect
l: the nominal length of a cut line
d: the separation between cut lines in the x-direction
dd: the nominal separation between cut lines in the y-direction
l will be adjusted so that there is an integral number of cuts in the x-direction.
dd will be adjusted so that there is an integral number of cuts in the y-direction.
"""
ret = []
# use l as a starting guess. Adjust it so that we get an integer number of cuts in the y-direction
# First compute the number of cuts in the x-direction using l. This will not in general be an integer.
p = (dx-d)/(d+l)
#round p to the nearest integer
p = round(p)
#compute the new l that will result in p cuts in the x-direction.
if p == 0:
p = 1 #avoid divison by zero
l = (dx-d)/p - d
# use dd as a starting guess. Adjust it so that we get an even integer number of cut lines in the y-direction.
p = dy/dd
p = round(p)
if p % 2 == 1:
p = p + 1
dd = dy/p
#
# Rows A cuts
#
curry = 0
doney = False
while not doney:
donex = False
startx = 0
endx = (l + d)/2.0
while not donex:
if endx >= dx:
endx = dx
# Add the end points of the line
ret.append({'x1' : x + startx, 'y1' : y + curry, 'x2': x + endx, 'y2': y + curry})
startx = endx + d
endx = startx + l
if startx >= dx:
donex = True
curry = curry + dd * 2.0
if curry - dy > dd:
doney = True
#
# Rows B cuts
#
curry = dd
doney = False
while not doney:
donex = False
startx = d
endx = startx + l
while not donex:
if endx >= dx:
endx = dx
# create a line
ret.append({'x1' : x + startx, 'y1' : y + curry, 'x2': x + endx, 'y2': y + curry})
startx = endx + d
endx = startx + l
if startx >= dx:
donex = True
curry = curry + dd*2.0
if curry > dy:
doney = True
return (ret, l, d, dd)
if __name__ == '__main__':
LivingHinge().run()