Contact point missmatch with road(s) connected to common junction on both ends

[johschmitz]

I am trying to find an issue with the create_junction() method when I create a "8" track with two arc roads directly connected to a four way junction at both of their ends.

Link to the method: https://github.com/pyoscx/scenariogeneration/blob/d9911c161904d2a24ecb035e173ade2376efabb7/scenariogeneration/xodr/generators.py#L976

It seems that in this case the contact points are not set correctly.

I thought that maybe inside the method I would have to replace

conne1 = Connection(jr.successor.element_id, jr.id, ContactPoint.end)

with

conne1 = Connection(jr.successor.element_id, jr.id, jr.successor.contact_point)

in order to fix it but it still does not seem to work completely. Maybe there is also a related bug in esmini or maybe I am just doing something wrong on my end. I can sit and work out a minimal example if needed to solve this or maybe you see it immediately. Just let me know.

[MandolinMicke]

That function is slightly outdated, but there to keep backwards compability. But that function is very sensitive that all predecessors and successors are set properly, the only tip I can give is that.

Have you tried using the new JunctionCreator class instead, it's more generic and can handle much more

[johschmitz]

I guess I will then have a look if the new API can now work for my use case and/or build a minimal example to understand exactly what is going wrong. I think the problem was that no custom connecting roads were supported and then I had to write some of the low level code myself and used this old method so that I did at least not have to write everything on my own.

[MandolinMicke]

Ah, but did you try out the change I made in a branch https://github.com/pyoscx/scenariogeneration/issues/127#issuecomment-1316574691?

[johschmitz]

So far I did not find time to try this to be honest, since the other approach was working and there was a lot of changes and bugfixes I needed to do first. Just came back to this point this week. I think this bug that I have now is a good reason though to revisit this topic.

[johschmitz]

@MandolinMicke I am playing with the common junction generator now and I noticed one thing which is a little bit confusing. There is a method called add_connection() which actually creates an OpenDRIVE connecting road. A "connection" is defined slightliy differently in the OpenDRIVE standard. See "t_junction_connection" in the UML Model (https://opendrive-uml.web.app/index.html?goto=2:54 or Chapter 10.2. Incoming roads in OpenDRIVE 1.7). You might want to overthink this name. Maybe call it create_connecting_road() and deprecate the add_connection() and remove it after some time or so.

[johschmitz]

I am trying to build the 8 course with two roads and one junction but it does not quite work:

import os
from scenariogeneration import xodr
from math import pi

# Initalize the junction creator
junction_id = 100
junction_creator = xodr.DirectJunctionCreator(id=junction_id, name="my direct junction")

# Create 2 roads, and add the successor/predecessor junction

road1 = xodr.create_road(xodr.Arc(curvature=0.1, angle=3/2*pi), id=1, left_lanes=1, right_lanes=1)
road2 = xodr.create_road(xodr.Arc(curvature=0.1, angle=3/2*pi), id=2, left_lanes=1, right_lanes=1)

# Create direct junction connection to all common lanes between the main roads

junction_creator = xodr.CommonJunctionCreator(id=100, name="my_junction")

junction_creator.add_incoming_road_cartesian_geometry(
    road1, x=0, y=0, heading=0, road_connection="predecessor"
)

junction_creator.add_incoming_road_cartesian_geometry(
    road1, x=10, y=10, heading=pi/2, road_connection="successor"
)

junction_creator.add_incoming_road_cartesian_geometry(
    road2, x=20, y=0, heading=pi, road_connection="predecessor"
)

junction_creator.add_incoming_road_cartesian_geometry(
    road2, x=10, y=-10, heading=-pi/2, road_connection="successor"
)

# Create the opendrive
odr = xodr.OpenDrive("my_road")

# Add the roads
junction_creator.add_connection(
    road_one_id=1, road_two_id=2, lane_one_id=1, lane_two_id=1
)
junction_creator.add_connection(
    road_one_id=2, road_two_id=1, lane_one_id=-1, lane_two_id=1
)

odr.add_road(road1)
odr.add_road(road2)

# Add the junction creator
odr.add_junction_creator(junction_creator)

# Adjust the roads and lanes
odr.adjust_roads_and_lanes()

# Write the OpenDRIVE file as xodr using current script name
odr.write_xml(os.path.basename(__file__).replace(".py", ".xodr"))

Any idea how to do this? Or should this not be allowed?

Probably I have to try with your branch next but I am not sure if this solves the problem. I guess there needs to be an additional argument to specify which end of the road to connect to.

[johschmitz]

One additional comment: I could maybe just disallow/prevent this case in my tool to work around this problem and I would be okay with that but it would be nicer if it would work.

[mander76]

so you are trying to create an 8 shaped road? Haven't tried this before.. But my spontaneous thought is that scenariogeneration will not handle this at all... I can maybe see some real life applications for these, but for sure they are not supported now

[MandolinMicke]

This one was solved in the end right? @johschmitz

[johschmitz]

Hm I need to check later. I am not sure if this one was solved or a similar one. Do you have some kind of unit test though with only one junction and a single road that connects to that junction on both ends?

[mander76]

not unittest no, there are some of these I would like to add tests to..