import copy
# TODO bend legs?
[docs]def auto_bend(ifd, deepcopy=False):
"""Automatically bend lines to avoid overlaps."""
if deepcopy:
fd = copy.deepcopy(ifd)
else:
fd = ifd
objs = fd.propagators
duplications = [0] * len(objs)
for i, pa in enumerate(objs):
for j, pb in enumerate(objs):
if pa.target == pb.target and pa.source == pb.source:
duplications[i] += 1
if pa.target == pb.source and pa.source == pb.target:
duplications[i] += 1
for i, pa in enumerate(objs):
if duplications[i] == 1:
pass
elif duplications[i] == 2:
for j, pb in enumerate(objs):
if i < j:
if pa.target == pb.target and pa.source == pb.source:
pa.bend = True
pa.style.setProperty("bend-direction", "right")
pb.bend = True
pb.style.setProperty("bend-direction", "left")
if pa.target == pb.source and pa.source == pb.target:
pa.bend = True
pa.style.setProperty("bend-direction", "left")
pb.bend = True
pb.style.setProperty("bend-direction", "left")
elif duplications[i] == 3:
for j, pb in enumerate(objs):
for k, pc in enumerate(objs):
# pc is the third propagator we keep it straight
if i < j and j < k:
if pa.target == pb.target and pa.source == pb.source:
pa.bend = True
pa.style.setProperty("bend-direction", "right")
pb.bend = True
pb.style.setProperty("bend-direction", "left")
if pa.target == pb.source and pa.source == pb.target:
pa.bend = True
pa.style.setProperty("bend-direction", "left")
pb.bend = True
pb.style.setProperty("bend-direction", "left")
else:
raise ValueError(
f"Too many propagators between the same vertices. {duplications[i]} propagators between {pa.target} and {pa.source}."
)
# print(pa.target, pb.target, pa.source, pb.source)
for p in objs:
if p.target == p.source:
p.bend = True
ref = []
for c in fd.propagators:
if c.target == p.target:
ref += [fd.get_vertex(c.source)]
if c.source == p.target:
ref += [fd.get_vertex(c.target)]
sumrefx = 0
sumrefy = 0
me = fd.get_vertex(p.target)
for r in ref:
sumrefx += r.x - me.x
sumrefy += r.y - me.y
dir = "up"
if sumrefy > 0:
dir = "down"
else:
dir = "up"
if dir == "up":
b_in = 45
b_out = 135
if dir == "down":
b_in = -45
b_out = -135
p.style.setProperty("bend-in", b_in)
p.style.setProperty("bend-out", b_out)
p.style.setProperty("bend-min-distance", "2cm")
p.style.setProperty("bend-loop", True)
return fd