inkstitch/lib/commands.py

87 wiersze
2.8 KiB
Python

import inkex
import cubicsuperpath
from .svg import apply_transforms
from .svg.tags import SVG_USE_TAG, SVG_SYMBOL_TAG, CONNECTION_START, CONNECTION_END, XLINK_HREF
class Command(object):
def __init__(self, connector):
self.connector = connector
self.svg = self.connector.getroottree().getroot()
self.parse_command()
def get_node_by_url(self, url):
# url will be #path12345. Find the object at the other end.
if url is None:
raise ValueError("url is None")
if not url.startswith('#'):
raise ValueError("invalid connection url: %s" % url)
id = url[1:]
try:
return self.svg.xpath(".//*[@id='%s']" % id)[0]
except (IndexError, AttributeError):
raise ValueError("could not find node by url %s" % id)
def parse_connector_path(self):
path = cubicsuperpath.parsePath(self.connector.get('d'))
return apply_transforms(path, self.connector)
def parse_command(self):
path = self.parse_connector_path()
neighbors = [
(self.get_node_by_url(self.connector.get(CONNECTION_START)), path[0][0][1]),
(self.get_node_by_url(self.connector.get(CONNECTION_END)), path[0][-1][1])
]
if neighbors[0][0].tag != SVG_USE_TAG:
neighbors.reverse()
if neighbors[0][0].tag != SVG_USE_TAG:
raise ValueError("connector does not point to a use tag")
self.symbol = self.get_node_by_url(neighbors[0][0].get(XLINK_HREF))
if self.symbol.tag != SVG_SYMBOL_TAG:
raise ValueError("use points to non-symbol")
self.command = self.symbol.get('id')
if self.command.startswith('inkstitch_'):
self.command = self.command[10:]
else:
raise ValueError("symbol is not an Ink/Stitch command")
self.target = neighbors[1][0]
self.target_point = neighbors[1][1]
def __repr__(self):
return "Command('%s', %s)" % (self.command, self.target_point)
def find_commands(node):
"""Find the symbols this node is connected to and return them as Commands"""
# find all paths that have this object as a connection
xpath = ".//*[@inkscape:connection-start='#%(id)s' or @inkscape:connection-end='#%(id)s']" % dict(id=node.get('id'))
connectors = node.getroottree().getroot().xpath(xpath, namespaces=inkex.NSS)
# try to turn them into commands
commands = []
for connector in connectors:
try:
commands.append(Command(connector))
except ValueError:
# Parsing the connector failed, meaning it's not actually an Ink/Stitch command.
pass
return commands
def is_command(node):
return CONNECTION_START in node.attrib or CONNECTION_END in node.attrib