JOGL and Swogl are both great libraries, bringing the power of OpenGL to the Java desktop. However, we have experienced problems when it comes to high quality text rendering. OpenGL does not support text rendering at all. But JOGL provides some experimental workarounds, some of them looking quite promising (like the GPU accelerated Text Demo). Nevertheless we wanted to switch to a much more stable graphics library to minimize the effort of graphics programming and spend more time for music notation issues.
We had a look on JavaFX, which also looks promising, but still has a long way to go to be ready for read world-applications. Qt is great, but the Qt Java binding is outdated and more or less dead. One evening when we tried Java 2D / AWT again, we were surprised by its speed. Back in the days when we began to work on Zong!, it was incredibly slow, but its performance has been greatly improved in Java 6 (and maybe 7). Now we are able to paint pages with about 1500 musical symbols (SVG paths) with about 30 frames per second! Welcome back, AWT 🙂
Here is a new screenshot of the Zong! Editor, showing some symbols and text, which are now rendered sharply at each zoom level: