diff options
Diffstat (limited to '')
| -rwxr-xr-x | share/extensions/motion.py | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/share/extensions/motion.py b/share/extensions/motion.py new file mode 100755 index 0000000..9ceab4a --- /dev/null +++ b/share/extensions/motion.py @@ -0,0 +1,174 @@ +#!/usr/bin/env python +# coding=utf-8 +# +# Copyright (C) 2005 Aaron Spike, aaron@ekips.org +# +# 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. +# +"""Adds a "drop shadow" to any selected number of path objects. Optionally, the stroke +color can be used for the shadow""" + +import math + +import inkex +from inkex.paths import ( + Move, + Line, + Curve, + ZoneClose, + Arc, + Path, + Vert, + Horz, + TepidQuadratic, + Quadratic, + Smooth, +) +from inkex.transforms import Vector2d +from inkex.bezier import beziertatslope, beziersplitatt + + +class Motion(inkex.EffectExtension): + """Generate a motion path""" + + def add_arguments(self, pars): + pars.add_argument( + "-a", + "--angle", + type=float, + default=45.0, + help="direction of the motion vector", + ) + pars.add_argument( + "-m", + "--magnitude", + type=float, + default=100.0, + help="magnitude of the motion vector", + ) + pars.add_argument( + "-f", + "--fillwithstroke", + type=inkex.Boolean, + default=False, + help="fill shadow with stroke color if set", + ) + + @staticmethod + def makeface(last, segment, facegroup, delx, dely): + """translate path segment along vector""" + elem = facegroup.add(inkex.PathElement()) + + npt = segment.translate([delx, dely]) + + # reverse direction of path segment + if isinstance(segment, Curve): + rev = Curve(npt.x3, npt.y3, npt.x2, npt.y2, last[0] + delx, last[1] + dely) + elif isinstance(segment, Line): + rev = Line(last[0] + delx, last[1] + dely) + else: + raise RuntimeError("Unexpected segment type {}".format(type(segment))) + + elem.path = inkex.Path( + [ + Move(last[0], last[1]), + segment, + npt.to_line(Vector2d()), + rev, + ZoneClose(), + ] + ) + + def effect(self): + delx = math.cos(math.radians(self.options.angle)) * self.options.magnitude + dely = math.sin(math.radians(self.options.angle)) * self.options.magnitude + for node in self.svg.selection.filter_nonzero(inkex.PathElement): + group = node.getparent().add(inkex.Group()) + facegroup = group.add(inkex.Group()) + group.append(node) + + # we want delx and dely values to be correct even for the transformed path, + # so transform them back, but ignore the translate of the transform + trans = -node.transform + local_delx = trans.a * delx + trans.c * dely + local_dely = trans.b * delx + trans.d * dely + + if node.transform: + group.transform = node.transform + node.transform = None + + facegroup.style = node.style + if self.options.fillwithstroke: + stroke = facegroup.style("stroke") + if stroke is not None and isinstance(stroke, inkex.Color): + facegroup.style["fill"] = stroke + facegroup.style["fill-opacity"] = facegroup.style("stroke-opacity") + reset_origin = True + for cmd_proxy in node.path.to_absolute().proxy_iterator(): + # for each subpath, reset the origin of the following computations to the first + # node of the subpath -> i.e. after a Z command, move the origin to the end point + # of the next command + if reset_origin: + first_point = cmd_proxy.end_point + reset_origin = False + if isinstance(cmd_proxy.command, ZoneClose): + reset_origin = True + self.process_segment( + cmd_proxy, facegroup, local_delx, local_dely, first_point + ) + + @staticmethod + def process_segment(cmd_proxy, facegroup, delx, dely, first_point): + """Process each segments""" + + segments = [] + if isinstance( + cmd_proxy.command, (Curve, Smooth, TepidQuadratic, Quadratic, Arc) + ): + prev = cmd_proxy.previous_end_point + for curve in cmd_proxy.to_curves(): + bez = [prev] + curve.to_bez() + prev = curve.end_point(cmd_proxy.first_point, prev) + tees = [t for t in beziertatslope(bez, (dely, delx)) if 0 < t < 1] + tees.sort() + if len(tees) == 1: + one, two = beziersplitatt(bez, tees[0]) + segments.append(Curve(*(one[1] + one[2] + one[3]))) + segments.append(Curve(*(two[1] + two[2] + two[3]))) + elif len(tees) == 2: + one, two = beziersplitatt(bez, tees[0]) + two, three = beziersplitatt(two, tees[1]) + segments.append(Curve(*(one[1] + one[2] + one[3]))) + segments.append(Curve(*(two[1] + two[2] + two[3]))) + segments.append(Curve(*(three[1] + three[2] + three[3]))) + else: + segments.append(curve) + elif isinstance(cmd_proxy.command, (Line, Curve)): + segments.append(cmd_proxy.command) + elif isinstance(cmd_proxy.command, ZoneClose): + segments.append(Line(*first_point)) + elif isinstance(cmd_proxy.command, (Vert, Horz)): + segments.append(cmd_proxy.command.to_line(cmd_proxy.end_point)) + + for seg in Path( + [Move(*cmd_proxy.previous_end_point)] + segments + ).proxy_iterator(): + if isinstance(seg.command, Move): + continue + Motion.makeface(seg.previous_end_point, seg.command, facegroup, delx, dely) + + +if __name__ == "__main__": + Motion().run() |