inkstitch/lib/svg/path.py

101 wiersze
3.0 KiB
Python

# Authors: see git history
#
# Copyright (c) 2010 Authors
# Licensed under the GNU GPL version 3.0 or later. See the file LICENSE for details.
import inkex
from .tags import SVG_GROUP_TAG, SVG_LINK_TAG
from .units import get_viewbox_transform
def apply_transforms(path, node):
transform = get_node_transform(node)
# apply the combined transform to this node's path
path = path.transform(transform)
return path
def compose_parent_transforms(node, mat):
# This is adapted from Inkscape's simpletransform.py's composeParents()
# function. That one can't handle nodes that are detached from a DOM.
trans = node.get('transform')
if trans:
mat = inkex.transforms.Transform(trans) * mat
if node.getparent() is not None:
if node.getparent().tag in [SVG_GROUP_TAG, SVG_LINK_TAG]:
mat = compose_parent_transforms(node.getparent(), mat)
return mat
def get_node_transform(node):
"""
if getattr(node, "composed_transform", None):
return node.composed_transform()
"""
# start with the identity transform
transform = inkex.transforms.Transform([[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]])
# this if is because sometimes inkscape likes to create paths outside of a layer?!
if node.getparent() is not None:
# combine this node's transform with all parent groups' transforms
transform = compose_parent_transforms(node, transform)
# add in the transform implied by the viewBox
viewbox_transform = get_viewbox_transform(node.getroottree().getroot())
transform = viewbox_transform * transform
return transform
def get_correction_transform(node, child=False):
"""Get a transform to apply to new siblings or children of this SVG node"""
# if we want to place our new nodes in the same group/layer as this node,
# then we'll need to factor in the effects of any transforms set on
# the parents of this node.
if child:
transform = get_node_transform(node)
else:
# we can ignore the transform on the node itself since it won't apply
# to the objects we add
transform = get_node_transform(node.getparent())
# now invert it, so that we can position our objects in absolute
# coordinates
transform = -transform
return str(transform)
def line_strings_to_csp(line_strings):
return point_lists_to_csp(ls.coords for ls in line_strings)
def point_lists_to_csp(point_lists):
csp = []
for point_list in point_lists:
subpath = []
for point in point_list:
# cubicsuperpath is very particular that these must be lists, not tuples
point = list(point)
# create a straight line as a degenerate bezier
subpath.append([point, point, point])
csp.append(subpath)
return csp
def line_strings_to_path(line_strings):
csp = line_strings_to_csp(line_strings)
return inkex.PathElement(attrib={
"d": str(inkex.paths.CubicSuperPath(csp))
})