The primary goal of this update is preparing for the v4.0 release: v3.5.10 will not be able to offer the v4.0 update, but v3.5.11 will. I’m not a fan of putting out an update for purely infrastructure purposes so I’ve also reverse-ported a handful of low-risk improvements from the v4.0 code base. This way we all win.

As usual, you can download it directly from the website or you can use the built-in updater via Utilities –> Check for Updates.

Here are the changes for this release:

  • Fixed: The Gaussian Blur effect was incorrectly calculating alpha values for non-opaque pixels. (
  • Improved performance of the Sharpen effect by about 25%
  • Improved performance of the Median effect by about 30%
  • Improved performance of the Fragment effect by about 40%
  • Improved performance of the Unfocus effect by about 100%
  • Reduced memory usage when many selection manipulation operations are in the history/undo stack (the undo data is now saved to disk)
  • The built-in updater now supports upgrading to 4.0 (once it’s available)

When I announced the beta for v3.5.11, I also talked a little about 4.0 and the progress that’s been made. If you haven’t read that, please catch up!

There have been rumors floating around that Paint.NET is “dead.” This is not true! Smile The 4.0 update has simply been a huge project, and I only have a limited amount of time at my disposal. (Apparently if you go 22 months without an update, that means “dead” in Internet years. Sorry!) Plus, sometimes you just want to go out and enjoy summer instead of writing code.

For comparison, v3.5.11 is about 203,000 lines of code, whereas v4.0 is at about 391,000. What’s new? Well, it has a brand new, asynchronous, fully multithreaded, hardware accelerated (via Direct2D) rendering engine that performs very happily with huge and large images, all while consuming less memory than v3.5. I’m not exaggerating the performance scaling either: whether you’ve got a 16-core Dual Xeon or a 400 megapixel image, 4.0 will be quite happy (other combinations are also very copacetic, of course).

The whole UI has been updated to use newer rendering toolkits such as Direct2D and DirectWrite, and the main window has a greatly simplified and consolidated layout. All of the drawing tools have been updated to use the new rendering system along with a new “fine-grained” history system (to clarify: the UI for history is the same, but the underlying code is radically different). It’s made possible a much richer “WYSIWYG” model for editing which is exemplified by the new Paint Bucket and Magic Wand tools. Selection rendering quality and performance are way up. The brush tools (Paintbrush, Eraser, Clone Stamp, Recolor) now support soft brushes, and the new Shapes tool replaces the 4 separate shape tools that are in v3.5 while providing many more shapes to use. There are also a bunch of other small, miscellaneous improvements that span across the UI and tools, including things like “Copy Merge” and antialiased selection rendering.

Anyway, enjoy!