See the FAQ section
This is a JDK13 runnable port of GeckoCircuits. The main goal was to enable HiDPI monitors to display GeckoCircuits in reasonable size.
The original Readme can be found here
All the source is from the original author. We just modified it such that it runs with JDK13 and also set up a more or less sane Maven project.
Technokrat GmbH takes no credit whatsoever on the original codebase.
To build, you need maven 3 installed and a more recent JDK. Everything from JDK9 to JDK13 should work.
Then run
mvn package
mvn package assembly:single
This should build the target/gecko-1.0-jar-with-dependencies.jar.
It should have a proper class path set and includes all the dependency libs.
Run it with
java -jar target/gecko-1.0-jar-with-dependencies.jar
To run on HiDPI screens, use
java -Dsun.java2d.uiScale=2 -jar gecko-1.0-jar-with-dependencies.jar
As you might have recognized during the build, 11 tests were skipped. Those were excluded as the codebase is hard to read and the tests only seem to fail because of some expectations how the environment should luck which is not given outside Netbeans.
Feel free to fix those tests.