Performance improvements in Substance 5
The biggest pain point of Substance users, as expressed in the comments on the announcement of release 4.3, is the performance. While this might have been less noticeable for smaller UIs, the users of Substance NetBeans module were especially vocal about the performance issue. You made your statement very clear, and performance improvements were placed as the top priority for the next release (code named Substance 5).
Following the extensive correspondence with Java2D team (thanks, Dmitri), i have created a new java.net project named LightBeam. LightBeam has a collection of static and dynamic scenarios that are targetting different core Swing components and different interaction scenarios. The static scenarios create a number of components and then render the main frame onto an offscreen buffer. The dynamic scenarios run a number of typical interaction scenarios that involve changing the components or models.
Here is the spreadsheet with the performance improvements on static scenarios. The numbers are milliseconds it takes to render a frame with a number of matching components (buttons, sliders etc) to an offscreen buffer (the smaller, the better).
An average improvement from version 4.3 is by factor of 3.5. As you can see, slider rendering was especially slow in version 4.3. Another important number to notice is the heap memory consumption - it has not grown at all as compared with version 4.3.
And here is the spreadsheet with the performance improvements on static scenarios. The numbers are milliseconds it takes to run a specific scenario and repaint the contents (the smaller, the better).
An average performance improvement from version 4.3 is by factor of 2.5. As before, sliders were especially slow in version 4.3. Note that there is one scenario where the additional visuals provided by Substance prove to be still too costly - in dynamically selecting table rows. This would, obviously, have to be addressed before the final release.
Project LightBeam is targeted at look-and-feel developers that wish to test the performance of their libraries. The SVN repository contains a number of sample scripts that were used in creating the above spreadsheets. It will be extensively used throughout the development of Substance to make sure that there are no performance regressions from this moment forward.
The latest development drop of Substance 5 should be very stable. You