New Manhattan Router

[rsoika]

Hi,
after being unhappy with the origin Sprotty Manhattan Router now for 3 years, I have finally managed to develop a new Manhattan Router :-)

The router is based on the main idea of Sprotty. The difference is how this router reacts when a connected element is moved. The origin Sprotty router recalculates the entire route from scratch, which often produces a completely different path or at least you lost a individual route. My new ManhattanRouter instead preserves the existing routing points and only adjusts the corners adjacent to the moved element. The nearest corner slides along its axis to follow the element while all intermediate bend points remain untouched.

This leads to a more intuitive routing in general.

Bildschirmaufzeichnung.vom.2026-03-21.08-56-21.webm

Modeling very complex models is making now fun.

I would like to contribute this new router to GLSP if you think it is worth. You can see my implementation here:
https://github.com/imixs/open-bpmn/blob/master/open-bpmn.glsp-client/open-bpmn-glsp/src/bpmn-manhattan-router.tsx
It is well documented so you can see what the router really does. (you know, I don't like uncommented source code ;-)

In my project the router is named BPMNManhattanRouter but this is just because it was developed within Open-BPMN. If the router makes it into the GLSP project, you could simply call it something like ManhattanRouter2 with a new KIND and we offer it as an alternative.

What do you all think about that?

Greetings
Ralph

[martin-fleck-at]

Hi @rsoika,

I think your router is definitely worth integrating your router into GLSP! It looks really great from the video and I can imagine many people looking exactly for such a bevhavior!

Overall, I think it makes more sense to give it a unique name and kind, such as "StickyManhattanRouter" because most of the route sticks to the original shape, to ensure that downstream projects are not getting their routing overwritten. Would you be willing to open a PR for it so we could do a proper code and integration review or are you offering for us to do that?

Cheers,
Martin

[rsoika]

Hi Martin,
I think that it is much easier for you to transfer the code into a new StickyManhattanRouter class than it is for me to create a pull request. Especially how the router then needs to be integrated into GLSP are things that I am not very familiar with or would have to spend an immense amount of time on.
I would be proud if you integrate the code into to glsp project. And we will see the community feedback.

===
Ralph

[martin-fleck-at]

Hi Ralph, sure thing! Then we will schedule some time in our team to integrate the router into GLSP. If there are any questions, we will definitely ask you on the PR if that is fine with you.

[rsoika]

Great! :-)

[martin-fleck-at]

eclipse-glsp/glsp-client#486. I made one change that seemed reasonable to me but if you have any concerns, please let me know: https://github.com/eclipse-glsp/glsp-client/pull/486/changes#diff-d93d025f2a6c75158399424f290042eb42fb0798f2cd75181a19a99398d44441R190-R194. I cannot add you as a reviewer unfortunately but I would be interested in your feedback.