Licensing of plugin that reuses a lot of code

[WouterSpekkink]

I developed a new layout plugin because I needed it for my own research. When I say "I developed" I actually mean that I took a lot of code from the original ForceAtlas 2 Layout plugin, stripped some of the code that I didn't need, and added some other stuff that I was missing. It is basically an adapted version of the ForceAtlas 2 plugin.

What does it do? In my research I make event graphs, where events are represented by nodes and the relationships between events are represented by arcs. I wanted to layout the events in chronological order on the x-axis, and I use the y-axis to distinguish between parallel subsequences. Using some of the code of the Force Atlas 2 plugin, the layout plugin that I made uses a user-supplied double variable to put the events in chronological order, and it pushes different subsequences away from each other on the y-axis, using the exact same logic as the original Force Atlas plugins. If you have a lot of events this feature saves a lot of time in making the event graphs look organized.

Anyway, I think it is time to share the plugin, and I have a question about licensing and acknowledgements. I found the standard license text that is also in the original Force Atlas 2 plugin. Am I just supposed to use that one and put my own name in there? How do I indicate in a good way that the code was actually mostly taken from the Force Atlas 2 plugin? I would also like to acknowledge the authors of the GeoLayout plugin, because I took quite some inspiration from their code.

Thank you in advance for the help.

[admin]

Hello,

You need to retain the copyright header in the source code that claim the orinal author. You may edit it to add your name and add details on your contribution. The license should be the GPL at least because the plugin was released in GPL and CDDL.

For all the rest you're free to write a readme

[WouterSpekkink]

Thank you for the reply. I retained the original copyright header (with the original author) in all the source code files. I made a small note in the source code file where I changed a few things. I also imported the GPL license, so I think it should be okay.