VAquaRendering – Java Native Rendering for macOS

The VAquaRendering package supports rendering of UI components using native code on macOS. The package is designed to support alternative implementations.

The entry point to this package is the AquaNativeRendering class, which uses the best available implementation.

These implementations are currently available:

• An implementation that renders by creating actual AppKit views and drawing them into a raster buffer. Similar techniques are used by browsers to simulate native check boxes and other controls. This implementation is a proof of concept with little optimization beyond caching of rendered images. There are some unavoidable limitations to this approach.
• An implementation that uses the same native rendering framework used by most AppKit views. Where possible, the (supported and minimally documented) Java Runtime Support framework API is used to access the native rendering.
• An implementation that uses classes from the JDK Aqua look and feel, which provide an optimized, but restricted path to the native rendering framework via the Java Runtime Support framework. This implementation is the most efficient but also has the most restrictions. This implementation may not work in future releases of the JDK where access to Aqua look and feel classes may be restricted.
• A hybrid implementation that selects from the above implementations to provide the best performance and the fewest restrictions.

All implementations use some Java simulations to work around limitations of the native rendering code.

Note that use of the Java Runtime Support framework on OS 10.10 (Yosemite) requires an upgraded version. The upgraded version is installed by the Java for OS X 2017-001 update.