def process_crossings(network):
"""
This is the simple version of process_crossing for the case that there is only one crossing
and to generate planar groundtruss.
"""
crossings=network_find_crossings(network) # [(edg1_tup,edg2_tup), (( , ) , ( , )), ...]
for tup in crossings:
# find ver coordinates of the two crossing edges
e_1=network.edge_coordinates(tup[0][0], tup[0][1])
e_2=network.edge_coordinates(tup[1][0], tup[1][1])
# find the intersection of the two edges
xyz=lines_intersection_xy(e_1, e_2)
# delete the crossing edges
network.delete_edge(tup[0][0], tup[0][1])
network.delete_edge(tup[1][0], tup[1][1])
# add the vertex at intersection
ver_key=network.add_node(x=xyz[0], y=xyz[1], z=xyz[2])
# add the four new edges
network.add_edge(ver_key, tup[0][0])
network.add_edge(ver_key, tup[0][1])
network.add_edge(ver_key, tup[1][0])
network.add_edge(ver_key, tup[1][1])
return network
def network_count_crossings(network):
"""Count the number of crossings (pairs of crossing edges) in the network.
Parameters
----------
network : Network
A network object.
Returns
-------
int
The number of crossings.
Notes
-----
This algorithm assumes that the network lies in the XY plane.
"""
return len(network_find_crossings(network))
if __name__ == '__main__':
import compas
from compas.datastructures import Network
from compas.datastructures import network_is_planar
from compas.datastructures import network_find_crossings
from compas.plotters import NetworkPlotter
network = Network.from_obj(compas.get('lines.obj'))
network.add_edge(6, 15)
if not network_is_planar(network):
crossings = network_find_crossings(network)
else:
crossings = []
print(crossings)
plotter = NetworkPlotter(network)
plotter.draw_vertices(radius=0.15,
text={key: key
for key in network.vertices()})
plotter.draw_edges(
color={edge: '#ff0000'
for edges in crossings for edge in edges})
plotter.show()