521 lines
25 KiB
Python
521 lines
25 KiB
Python
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#!/usr/bin/env python3
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# coding=utf-8
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#
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# Copyright (C) 2020 Juergen Weigert, jnweiger@gmail.com
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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#
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# v0.1, 2020-11-08, jw - initial draught, finding and printing selected nodes to the terminal...
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# v0.2, 2020-11-08, jw - duplicate the selected nodes in their superpaths, write them back.
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# v0.3, 2020-11-21, jw - find "meta-handles"
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# v0.4, 2020-11-26, jw - alpha and trim math added. trimming with a striaght line implemented, needs fixes.
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# Option 'cut' added.
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# v0.5, 2020-11-28, jw - Cut operation looks correct. Dummy midpoint for large arcs added, looks wrong, of course.
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# v1.0, 2020-11-30, jw - Code completed. Bot cut and arc work fine.
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# v1.1, 2020-12-07, jw - Replaced boolean 'cut' with a method selector 'arc'/'line'. Added round_corners_092.inx
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# and started backport in round_corners.py -- attempting to run the same code everywhere.
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# v1.2, 2020-12-08, jw - Backporting continued: option parser hack added. Started effect_wrapper() to prepare self.svg
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# v1.3, 2020-12-12, jw - minimalistic compatibility layer for inkscape 0.92.4 done. It now works in both, 1.0 and 0.92!
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# v1.4, 2020-12-15, jw - find_roundable_nodes() added for auto selecting nodes, if none were selected.
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# And fix https://github.com/jnweiger/inkscape-round-corners/issues/2
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# 2021-01-15, Mario Voigt - removed oboslete InkScape 0.92.* stuff
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#
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# Bad side-effect: As the node count increases during operation, the list of
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# selected nodes is incorrect afterwards. We have no way to give inkscape an update.
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#
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"""
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Rounded Corners
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This extension operates on selected sharp corner nodes and converts them to a fillet (bevel,chamfer).
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An arc shaped path segment with the given radius is inserted smoothly.
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The fitted arc is approximated by a bezier spline, as we are doing path operations here.
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When the sides at the corner are straight lines, the operation never move the sides, it just shortens them to fit the arc.
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When the sides are curved, the arc is placed on the tanget line, and the curve may thus change in shape.
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Selected smooth nodes are skipped.
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Cases with insufficient space (180deg turn or too short segments/handles) are warned about.
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References:
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- https://gitlab.com/inkscape/extensions/-/wikis/home
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- https://gitlab.com/inkscape/extras/extensions-tutorials/-/blob/master/My-First-Effect-Extension.md
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- https://gitlab.com/inkscape/extensions/-/wikis/uploads/25063b4ae6c3396fcda428105c5cff89/template_effect.zip
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- https://inkscape-extensions-guide.readthedocs.io/en/latest/_modules/inkex/elements.html#ShapeElement.get_path
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- https://inkscape.gitlab.io/extensions/documentation/_modules/inkex/paths.html#CubicSuperPath.to_path
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- https://stackoverflow.com/questions/734076/how-to-best-approximate-a-geometrical-arc-with-a-bezier-curve
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- https://hansmuller-flex.blogspot.com/2011/10/more-about-approximating-circular-arcs.html
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- https://itc.ktu.lt/index.php/ITC/article/download/11812/6479 (Riskus' PDF)
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The algorithm of arc_bezier_handles() is based on the approach described in:
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A. Riškus, "Approximation of a Cubic Bezier Curve by Circular Arcs and Vice Versa,"
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Information Technology and Control, 35(4), 2006 pp. 371-378.
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"""
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import inkex
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import sys, math, pprint, copy
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__version__ = '1.4' # Keep in sync with round_corners.inx line 16
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debug = False # True: babble on controlling tty
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max_trim_factor = 0.90 # 0.5: can cut half of a segment length or handle length away for rounding a corner
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max_trim_factor_single = 0.98 # 0.98: we can eat up almost everything, as there are no neighbouring trims to be expected.
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class RoundedCorners(inkex.EffectExtension):
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def add_arguments(self, pars): # an __init__ in disguise ...
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try:
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self.tty = open("/dev/tty", 'w')
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except:
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try:
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self.tty = open("CON:", 'w') # windows. Does this work???
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except:
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self.tty = open(os.devnull, 'w') # '/dev/null' for POSIX, 'nul' for Windows.
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if debug: print("RoundedCorners ...", file=self.tty)
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self.nodes_inserted = {}
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self.eps = 0.00001 # avoid division by zero
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self.radius = None
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self.max_trim_factor = max_trim_factor
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self.skipped_degenerated = 0 # not a useful corner (e.g. 180deg corner)
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self.skipped_small_count = 0 # not enough room for arc
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self.skipped_small_len = 1e99 # record the shortest handle (or segment) when skipping.
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pars.add_argument("--radius", type=float, default=2.0, help="Radius [mm] to round selected vertices. Default: 2")
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pars.add_argument("--method", type=str, default="arc", help="operation: one of 'arc' (default), 'line'")
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def effect(self):
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if debug:
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# SvgInputMixin __init__: "id:subpath:position of selected nodes, if any"
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print(self.options.selected_nodes, file=self.tty)
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self.radius = math.fabs(self.options.radius)
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self.cut = False
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if self.options.method in ('line'):
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self.cut = True
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if len(self.options.selected_nodes) < 1:
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# find selected objects and construct a list of selected_nodes for them...
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for p in self.options.ids:
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self.options.selected_nodes.extend(self.find_roundable_nodes(p))
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if len(self.options.selected_nodes) < 1:
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raise inkex.AbortExtension("Could not find nodes inside a path. No path objects selected?")
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if len(self.options.selected_nodes) == 1:
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# when we only trim one node, we can eat up almost everything,
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# no need to leave room for rounding neighbour nodes.
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self.max_trim_factor = max_trim_factor_single
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for node in sorted(self.options.selected_nodes):
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## we walk through the list sorted, so that node indices are processed within a subpath in ascending numeric order.
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## that makes adjusting index offsets after node inserts easier.
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ss = self.round_corner(node)
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def find_roundable_nodes(self, path_id):
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""" select all nodes of all (sub)paths. except for
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- the last (one or two) nodes of a closed path (which coindide with the first node)
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- the first and last node of an open path (which cannot be smoothed)
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"""
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ret = []
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elem = self.svg.getElementById(path_id)
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if elem.tag != '{'+elem.nsmap['svg']+'}path':
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return ret # ellipse never works.
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try:
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csp = elem.path.to_superpath()
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except:
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return ret
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for sp_idx in range(0, len(csp)):
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sp = csp[sp_idx]
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if len(sp) < 3:
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continue # subpaths of 2 or less nodes are ignored
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if self.very_close(sp[0], sp[-1]):
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idx_s = 0 # closed paths count from 0 to either n-1 or n-2
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idx_e = len(sp) - 1
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if self.very_close_xy(sp[-2][1], sp[-1][1]):
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idx_e = len(sp) - 2
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else:
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idx_s = 1 # open paths count from 1 to either n-1
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idx_e = len(sp) - 1
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for idx in range(idx_s, idx_e):
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ret.append("%s:%d:%d" % (path_id, sp_idx, idx))
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if debug:
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print("find_roundable_nodes: ", self.options.selected_nodes, file=sys.stderr)
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return ret
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def very_close(self, n1, n2):
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"deep compare. all elements in sub arrays are compared for (very close) numerical equality"
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return self.very_close_xy(n1[0], n2[0]) and self.very_close_xy(n1[1], n2[1]) and self.very_close_xy(n1[2], n2[2])
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def very_close_xy(self, p1, p2):
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"one 2 element array is compared for (very close) numerical equality"
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eps = 1e-9
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return abs(p1[0]-p2[0]) < eps and abs(p1[1]-p2[1]) < eps
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def round_corner(self, node_id):
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""" round the corner at (adjusted) node_idx of subpath
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Side_effect: store (or increment) in self.inserted["pathname:subpath"] how many points were inserted in that subpath.
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the adjusted node_idx is computed by adding that number (if exists) to the value of the node_id before doing any manipulation
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"""
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s = node_id.split(":")
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path_id = s[0]
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subpath_idx = int(s[1])
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subpath_id = s[0] + ':' + s[1]
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idx_adjust = self.nodes_inserted.get(subpath_id, 0)
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node_idx = int(s[2]) + idx_adjust
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elem = self.svg.getElementById(path_id)
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if elem is None:
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print("selected_node %s not found in svg document" % node_id, file=sys.stderr)
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return None
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elem.apply_transform() # modifies path inplace? -- We save later back to the same element. Maybe we should not?
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path = elem.path
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s = path.to_superpath()
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sp = s[subpath_idx]
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## call the actual path manipulator, record how many nodes were inserted.
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orig_len = len(sp)
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sp = self.subpath_round_corner(sp, node_idx)
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idx_adjust += len(sp) - orig_len
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# convert the superpath back to a normal path
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s[subpath_idx] = sp
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elem.set_path(s.to_path(curves_only=False))
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self.nodes_inserted[subpath_id] = idx_adjust
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# If we picked up the 'd' attribute of a non-path (e.g. star), we must make sure the object now becomes a path.
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# Otherwise inkscape uses the sodipodi data and ignores our changed 'd' attribute.
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if '{'+elem.nsmap['sodipodi']+'}type' in elem.attrib:
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del(elem.attrib['{'+elem.nsmap['sodipodi']+'}type'])
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# Debugging is no longer available or not yet implemented? This explodes, although it is
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# documented in https://inkscape.gitlab.io/extensions/documentation/inkex.command.html
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# inkex.command.write_svg(self.svg, "/tmp/seen.svg")
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# - AttributeError: module 'inkex' has no attribute 'command'
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# But hey, we can always resort to good old ET.dump(self.document) ...
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def super_node(self, sp, node_idx):
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""" In case of node_idx 0, we need to use either the last, the second-last or the third last node as a previous node.
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For a closed subpath, the last node and the first node are identical. Then, the second last node may be still at the
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same location if it has a handle. If so, we take the third last instead. Gah. It has a certain logic...
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In case of the node_idx being the last node, we already know that the subpath is not closed,
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we use 0 as the next node.
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The direction sn.prev.dir does not really point to the coordinate of the previous node, but to the end of the
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next-handle of the prvious node. This is the same when there are straight lines. The absence of handles is
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denoted by having the same coordinates for handle and node.
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Same for next.dir, it points to the next.prev handle.
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The exact implementation here is:
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- sn.next.handle is set to a relative vector that is the tangent of the curve towards the next point.
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we implement four cases:
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- if neither node nor next have handles, the connection is a straight line, and next.handle points
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in the direction of the next node itself.
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- if the curve between node and next is defined by two handles, then sn.next.handle is in the direction of the
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nodes own handle,
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- if the curve between node and next is defined one handle at the node itself, then sn.next.handle is in the
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direction of the nodes own handle,
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- if the curve between node and next is defined one handle at the next node, then sn.next.handle is in the
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direction from the node to the end of that other handle.
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- when trimming back later, we move along that tangent, instead of following the curve.
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That is an approximation when the segment is curved, and exact when it is straight.
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(Finding exact candidate points on curved lines that have tangents with the desired circle
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is beyond me today. Multiple candidates may exist. Any volunteers?)
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"""
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prev_idx = node_idx - 1
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sp_node_idx_ = copy.deepcopy(sp[node_idx]) # if this wraps around, at node_idx=0, we may need to tweak the prev handle
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if node_idx == 0:
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prev_idx = len(sp) - 1
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if self.very_close(sp_node_idx_, sp[prev_idx]):
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prev_idx = prev_idx - 1 # skip one node, it is the 'close marker'
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if self.very_close_xy(sp_node_idx_[1], sp[prev_idx][1]):
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# still no distance, skip more. Needed for https://github.com/jnweiger/inkscape-round-corners/issues/2
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sp_node_idx_[0] = sp[prev_idx][0] # this sp_node_idx_ must acts as if its prev handle is that one.
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prev_idx = prev_idx - 1
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else:
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self.skipped_degenerated += 1 # path ends here.
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return None, None
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# if debug: pprint.pprint({'node_idx': node_idx, 'len(sp)':len(sp), 'sp': sp}, stream=self.tty)
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if node_idx == len(sp)-1:
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self.skipped_degenerated += 1 # path ends here. On a closed loop, we can never select the last point.
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return None, None
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next_idx = node_idx + 1
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if next_idx >= len(sp): next_idx = 0
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t = sp_node_idx_
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p = sp[prev_idx]
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n = sp[next_idx]
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dir1 = [ p[2][0] - t[1][0], p[2][1] - t[1][1] ] # direction to the previous node (rel coords)
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dir2 = [ n[0][0] - t[1][0], n[0][1] - t[1][1] ] # direction to the next node (rel coords)
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dist1 = math.sqrt(dir1[0]*dir1[0] + dir1[1]*dir1[1]) # distance to the previous node
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dist2 = math.sqrt(dir2[0]*dir2[0] + dir2[1]*dir2[1]) # distance to the next node
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handle1 = [ t[0][0] - t[1][0], t[0][1] - t[1][1] ] # handle towards previous node (rel coords)
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handle2 = [ t[2][0] - t[1][0], t[2][1] - t[1][1] ] # handle towards next node (rel coords)
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if self.very_close_xy(handle1, [ 0, 0 ]): handle1 = dir1
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if self.very_close_xy(handle2, [ 0, 0 ]): handle2 = dir2
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prev = { 'idx': prev_idx, 'dir':dir1, 'handle':handle1 }
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next = { 'idx': next_idx, 'dir':dir2, 'handle':handle2 }
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sn = { 'idx': node_idx, 'prev': prev, 'next': next, 'x': t[1][0], 'y': t[1][1] }
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if dist1 < self.radius:
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if debug:
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print("subpath node_idx=%d, dist to prev(%d) is smaller than radius: %g < %g" %
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(node_idx, prev_idx, dist1, self.radius), file=sys.stderr)
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pprint.pprint(sn, stream=sys.stderr)
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if self.skipped_small_len > dist1: self.skipped_small_len = dist1
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self.skipped_small_count += 1
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return None, None
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if dist2 < self.radius:
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if debug:
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print("subpath node_idx=%d, dist to next(%d) is smaller than radius: %g < %g" %
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(node_idx, next_idx, dist2, self.radius), file=sys.stderr)
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pprint.pprint(sn, stream=sys.stderr)
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if self.skipped_small_len > dist2: self.skipped_small_len = dist2
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self.skipped_small_count += 1
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return None, None
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len_h1 = math.sqrt(handle1[0]*handle1[0] + handle1[1]*handle1[1])
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len_h2 = math.sqrt(handle2[0]*handle2[0] + handle2[1]*handle2[1])
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prev['hlen'] = len_h1
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next['hlen'] = len_h2
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if len_h1 < self.radius:
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if debug:
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print("subpath node_idx=%d, handle to prev(%d) is shorter than radius: %g < %g" %
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(node_idx, prev_idx, len_h1, self.radius), file=sys.stderr)
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pprint.pprint(sn, stream=sys.stderr)
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if self.skipped_small_len > len_h1: self.skipped_small_len = len_h1
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self.skipped_small_count += 1
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return None, None
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if len_h2 < self.radius:
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if debug:
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print("subpath node_idx=%d, handle to next(%d) is shorter than radius: %g < %g" %
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(node_idx, next_idx, len_h2, self.radius), file=sys.stderr)
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pprint.pprint(sn, stream=sys.stderr)
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if self.skipped_small_len > len_h2: self.skipped_small_len = len_h2
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self.skipped_small_count += 1
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return None, None
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if len_h1 > dist1: # shorten that handle to dist1, avoid overshooting the point
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handle1[0] = handle1[0] * dist1 / len_h1
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handle1[1] = handle1[1] * dist1 / len_h1
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prev['hlen'] = dist1
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if len_h2 > dist2: # shorten that handle to dist2, avoid overshooting the point
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|
handle2[0] = handle2[0] * dist2 / len_h2
|
||
|
handle2[1] = handle2[1] * dist2 / len_h2
|
||
|
next['hlen'] = dist2
|
||
|
|
||
|
return sn, sp_node_idx_
|
||
|
|
||
|
|
||
|
def arc_c_m_from_super_node(self, s):
|
||
|
"""
|
||
|
Given the supernode s and the radius self.radius, we compute and return two points:
|
||
|
c, the center of the arc and m, the midpoint of the arc.
|
||
|
|
||
|
Method used:
|
||
|
- construct the ray c_m_vec that runs though the original point p=[x,y] through c and m.
|
||
|
- next.trim_pt, [x,y] and c form a rectangular triangle. Thus we can
|
||
|
compute cdist as the length of the hypothenuses under trim and radius.
|
||
|
- c is then cdist away from [x,y] along the vector c_m_vec.
|
||
|
- m is closer to [x,y] than c by exactly radius.
|
||
|
"""
|
||
|
|
||
|
a = [ s['prev']['trim_pt'][0] - s['x'], s['prev']['trim_pt'][1] - s['y'] ]
|
||
|
b = [ s['next']['trim_pt'][0] - s['x'], s['next']['trim_pt'][1] - s['y'] ]
|
||
|
|
||
|
c_m_vec = [ a[0] + b[0],
|
||
|
a[1] + b[1] ]
|
||
|
l = math.sqrt( c_m_vec[0]*c_m_vec[0] + c_m_vec[1]*c_m_vec[1] )
|
||
|
|
||
|
cdist = math.sqrt( self.radius*self.radius + s['trim']*s['trim'] ) # distance [x,y] to circle center c.
|
||
|
|
||
|
c = [ s['x'] + cdist * c_m_vec[0] / l, # circle center
|
||
|
s['y'] + cdist * c_m_vec[1] / l ]
|
||
|
|
||
|
m = [ s['x'] + (cdist-self.radius) * c_m_vec[0] / l, # spline midpoint
|
||
|
s['y'] + (cdist-self.radius) * c_m_vec[1] / l ]
|
||
|
|
||
|
return (c, m)
|
||
|
|
||
|
|
||
|
def arc_bezier_handles(self, p1, p4, c):
|
||
|
"""
|
||
|
Compute the control points p2 and p3 between points p1 and p4, so that the cubic bezier spline
|
||
|
defined by p1,p2,p3,p2 approximates an arc around center c
|
||
|
|
||
|
Algorithm based on Aleksas Riškus and Hans Muller. Sorry Pomax, saw your works too, but did not use any.
|
||
|
"""
|
||
|
x1,y1 = p1
|
||
|
x4,y4 = p4
|
||
|
xc,yc = c
|
||
|
|
||
|
ax = x1 - xc
|
||
|
ay = y1 - yc
|
||
|
bx = x4 - xc
|
||
|
by = y4 - yc
|
||
|
q1 = ax * ax + ay * ay
|
||
|
q2 = q1 + ax * bx + ay * by
|
||
|
k2 = 4./3. * (math.sqrt(2 * q1 * q2) - q2) / (ax * by - ay * bx)
|
||
|
|
||
|
x2 = xc + ax - k2 * ay
|
||
|
y2 = yc + ay + k2 * ax
|
||
|
x3 = xc + bx + k2 * by
|
||
|
y3 = yc + by - k2 * bx
|
||
|
|
||
|
return ([x2, y2], [x3, y3])
|
||
|
|
||
|
|
||
|
def subpath_round_corner(self, sp, node_idx):
|
||
|
sn, sp_node_idx_ = self.super_node(sp, node_idx)
|
||
|
if sn is None: return sp # do nothing. stderr messages are already printed.
|
||
|
|
||
|
# The angle to be rounded is now between the vectors a and b
|
||
|
#
|
||
|
a = sn['prev']['handle']
|
||
|
b = sn['next']['handle']
|
||
|
a_len = sn['prev']['hlen']
|
||
|
b_len = sn['next']['hlen']
|
||
|
try:
|
||
|
# From https://de.wikipedia.org/wiki/Schnittwinkel_(Geometrie)
|
||
|
# Wikipedia has an abs() in the formula, which extracts the smaller of the two angles.
|
||
|
# We don't want that. We need to distinguish betwenn spitzwingklig and stumpfwinklig.
|
||
|
#
|
||
|
alpha = math.acos( (a[0]*b[0]+a[1]*b[1]) / ( math.sqrt(a[0]*a[0]+a[1]*a[1]) * math.sqrt(b[0]*b[0]+b[1]*b[1]) ) )
|
||
|
except:
|
||
|
# Division by 0 error means path folds back on itself here. No space to apply a radius between the segments.
|
||
|
self.skipped_degenerated += 1
|
||
|
return sp
|
||
|
|
||
|
sn['alpha'] = math.degrees(alpha)
|
||
|
|
||
|
# find the amount to trim back both sides so that a circle of radius self.radius would perfectly fit.
|
||
|
if alpha < self.eps:
|
||
|
# path folds back on itself here. No space to apply a radius between the segments.
|
||
|
self.skipped_degenerated += 1
|
||
|
return sp
|
||
|
if abs(alpha - math.pi) < self.eps:
|
||
|
# stretched. radius won't be visible, that is just fine. No need to warn about that.
|
||
|
return sp
|
||
|
trim = self.radius / math.tan(0.5 * alpha)
|
||
|
sn['trim'] = trim
|
||
|
if trim < 0.0:
|
||
|
print("Error: at node_idx=%d: angle=%g°, trim is negative: %g" % (node_idx, math.degrees(alpha), trim), file=sys.stderr)
|
||
|
return sp
|
||
|
|
||
|
# a_len points to the previous node. There we can always allow max_trim_factor_single, as the trim was either already done,
|
||
|
# or will not be done. Only at b_len we need to reserve space for the next trim.
|
||
|
# FIXME: also allow max_trim_factor_single at b_len, when we find that the very next node will not be rounded.
|
||
|
#
|
||
|
available_len = min(max_trim_factor_single*a_len, self.max_trim_factor*b_len)
|
||
|
if trim > available_len:
|
||
|
if debug:
|
||
|
if trim > max_trim_factor_single*a_len:
|
||
|
print("Skipping where hlen_a %g * max_trim %g < needed_trim %g" % (a_len, max_trim_factor_single, trim), file=self.tty)
|
||
|
if trim > self.max_trim_factor*b_len:
|
||
|
print("Skipping where hlen_b %g * max_trim %g < needed_trim %g" % (b_len, self.max_trim_factor, trim), file=self.tty)
|
||
|
pprint.pprint(sn, stream=self.tty)
|
||
|
if self.skipped_small_len > available_len:
|
||
|
self.skipped_small_len = available_len
|
||
|
self.skipped_small_count += 1
|
||
|
return sp
|
||
|
trim_pt_p = [ sn['x'] + a[0] * trim / a_len, sn['y'] + a[1] * trim / a_len ]
|
||
|
trim_pt_n = [ sn['x'] + b[0] * trim / b_len, sn['y'] + b[1] * trim / b_len ]
|
||
|
sn['prev']['trim_pt'] = trim_pt_p
|
||
|
sn['next']['trim_pt'] = trim_pt_n
|
||
|
|
||
|
if debug:
|
||
|
pprint.pprint(sn, stream=self.tty)
|
||
|
pprint.pprint(self.cut, stream=self.tty)
|
||
|
# We replace the node_idx node by two nodes node_a, node_b.
|
||
|
# We need an extra middle node node_m if alpha < 90° -- alpha is the angle between the tangents,
|
||
|
# as the arc spans the remainder to complete 180° an arc with more than 90° needs the midpoint.
|
||
|
|
||
|
# We preserve the endpoints of the two outside handles if they are non-0-length.
|
||
|
# We know that such handles are long enough (because of the above max_trim_factor checks)
|
||
|
# to not flip around when applying the trim.
|
||
|
# But we move the endpoints of 0-length outside handles with the point when trimming,
|
||
|
# so that they don't end up on the inside.
|
||
|
prev_handle = sp_node_idx_[0][:]
|
||
|
next_handle = sp_node_idx_[2][:]
|
||
|
if self.very_close_xy(prev_handle, sp_node_idx_[1]): prev_handle = trim_pt_p[:]
|
||
|
if self.very_close_xy(next_handle, sp_node_idx_[1]): next_handle = trim_pt_n[:]
|
||
|
|
||
|
p1 = trim_pt_p[:]
|
||
|
p7 = trim_pt_n[:]
|
||
|
arc_c, p4 = self.arc_c_m_from_super_node(sn)
|
||
|
node_a = [ prev_handle, p1[:], p1[:] ] # deep copy, as we may want to modify the second handle later
|
||
|
node_b = [ p7[:], p7[:], next_handle ] # deep copy, as we may want to modify the first handle later
|
||
|
|
||
|
if alpha >= 0.5*math.pi or self.cut:
|
||
|
if self.cut == False:
|
||
|
# p3,p4,p5 do not exist, we need no midpoint
|
||
|
p2, p6 = self.arc_bezier_handles(p1, p7, arc_c)
|
||
|
node_a[2] = p2
|
||
|
node_b[0] = p6
|
||
|
if node_idx == 0:
|
||
|
# use prev idx to know about the extra skip. +1 for the node here, +1 for inclusive.
|
||
|
# CAUTION: Keep in sync below
|
||
|
sp = [node_a] + [node_b] + sp[1:sn['prev']['idx']+2]
|
||
|
else:
|
||
|
sp = sp[:node_idx] + [node_a] + [node_b] + sp[node_idx+1:]
|
||
|
else:
|
||
|
p2, p3 = self.arc_bezier_handles(p1, p4, arc_c)
|
||
|
p5, p6 = self.arc_bezier_handles(p4, p7, arc_c)
|
||
|
node_m = [ p3, p4, p5 ]
|
||
|
node_a[2] = p2
|
||
|
node_b[0] = p6
|
||
|
if node_idx == 0:
|
||
|
# use prev idx to know about the extra skip. +1 for the node here, +1 for inclusive.
|
||
|
# CAUTION: Keep in sync above
|
||
|
sp = [node_a] + [node_m] + [node_b] + sp[1:sn['prev']['idx']+2]
|
||
|
else:
|
||
|
sp = sp[:node_idx] + [node_a] + [node_m] + [node_b] + sp[node_idx+1:]
|
||
|
|
||
|
# A closed path is formed by making the last node indentical to the first node.
|
||
|
# So, if we trim at the first node, then duplicte that trim on the last node, to keep the loop closed.
|
||
|
if node_idx == 0:
|
||
|
sp[-1][0] = sp[0][0][:]
|
||
|
sp[-1][1] = sp[0][1][:]
|
||
|
sp[-1][2] = sp[0][2][:]
|
||
|
|
||
|
return sp
|
||
|
|
||
|
|
||
|
def clean_up(self): # __fini__
|
||
|
if self.tty is not None:
|
||
|
self.tty.close()
|
||
|
super(RoundedCorners, self).clean_up()
|
||
|
if self.skipped_degenerated:
|
||
|
print("Warning: Skipped %d degenerated nodes (180° turn or end of path?).\n" % self.skipped_degenerated, file=sys.stderr)
|
||
|
if self.skipped_small_count:
|
||
|
print("Warning: Skipped %d nodes with not enough space (Value %g is too small. Try again with a smaller radius or only one node selected).\n" % (self.skipped_small_count, self.skipped_small_len), file=sys.stderr)
|
||
|
|
||
|
|
||
|
if __name__ == '__main__':
|
||
|
RoundedCorners().run()
|