For a game engine I am writing, I am planning to use a heavily cut down and thoroughly modified version of the Java logging library logback. Basically I am using their code for lookups and instantiation of new loggers (so, maybe some 5% tops of the code, not that it matters).Q: What does this mean for my engine; What does the LGPL license force me to do?Addendum:I am not native speaker and hence have issues understanding all that legal mumbo-jumbo which forms the license.The question also is specifically about LGPL v2.1, as that is the license of the library I abuse.Addendum2: to clear some confusion; the phrase '... 5% ... not that it matters', refers to the fact that it does not matter how much or how little code it is in the end, it still is licensed code and hemce has to be treated in such a matter.
Am I allowed to make use of parts of the codebase of a library that is licensed under LGPL (v2.1)
lgpl
The license terms of the LGPL license effectively distinguish two different models:You make changes to the LGPL code, or you copy portions of the LGPL licensed code into your own project. In this case, the license requires you to make your code available under the LGPL or GPL license as a library that can be used by other programs.You use the LGPL licensed library in your application by linking to it. In this case, you must provide a way for your users to replace the library, but otherwise you are free to choose your license terms.Providing a way to replace the library is easiest if you link dynamically to it or of you publish your code under an open source license.In your case, your best option is to create a library of the cut-down version of logback and publish that under the LGPL. Then your game can link to this new library for its logging.