This update is chock full of bug fixes and is a big step toward the final/stable release, which I’m planning to coincide with the stable release of .NET 9 in November.

Change Log

Changes since 5.1 beta (build 9023):

• Fixed: The canvas tile renderer was using an extraordinary amount of memory when zooming out on a large image, which would then cause crashes.
• Fixed some rendering glitches in the Levels UI when resizing the window.
• Fixed some rendering glitches in the Curves UI when switching between transfer tables (Luminosity vs. RGB).
• Fixed some issues with the mouse cursor not being initialized correctly when performing certain operations, such as undo/redo or when drawing a line/curve. Instead of being a crosshair or hand, it would be the standard arrow cursor.
• Fixed an input state bug that made it possible for thumbnails to stop working if focus was lost while holding down the mouse button. For example, pressing Ctrl+N (for File->New) while using the Move Selected Pixels tool.
• Fixed the History window’s scrollbar (it was not drawing at all).
• Fixed some flickering that could happen in the History window when switching between images.
• Fixed some flickering in the toolbar that could happen when performing undo or redo operations.
• Fixed an error in the Levels UI that was preventing the output gamma values from updating correctly.
• Improved performance of Levels and Auto-Level, which should also significantly reduce the chance of them crashing on older Intel GPUs.
• Fixed a rendering glitch that could happen if the window was being resized while Ctrl+Tab was held down to switch between images. Some images would have their canvas in a cropped state that would only go away if the window was resized again.
• Changed the crash log format so that it is the same as that used for other in-app errors and Settings -> Diagnostics.

Download and Install

This build is available via the built-in updater as long as you have opted-in to pre-release updates. From within Settings -> Updates, enable “Also check for pre-release (beta) versions of paint.net” and then click on the Check Now button. You can also use the links below to download an offline installer or portable ZIP.

You can also download the installer here (for any supported CPU and OS), which is also where you can find downloads for offline installers, portable ZIPs, and deployable MSIs.

This is a relatively light update in the sense that you shouldn’t “see” any big changes.

Under the hood, however, there are some big changes. The first is that Paint.NET is now running on .NET 9.0, which has a lot of performance improvements over .NET 8.0. You can read about them all here. Some of those improvements are quite impactful for Paint.NET, including those that target startup performance and exception handling performance. This also ensures that plugins can keep making use of the latest runtime, framework, libraries, and tools.

The other big under-the-hood change is that I’ve migrated the UI presentation system from DirectComposition (aka “DComp”) to Windows.UI.Composition (aka “WUC”). The use of DComp was new in PDN v5.1, but WUC is actually what Microsoft recommends for newer apps (Win10+) and I wanted to be aligned with that. I originally thought that WUC was built on top of DComp, but I recently learned that isn’t true — they’re both APIs that provide interfaces to DWM (Desktop Window Manager), but WUC is the newer API. This just sets things up for success in the future if PDN needs to use Windows’ composition APIs for something more substantial.

Change Log

Changes since 5.1 beta (build 9004):

• Changed: Upgraded to use .NET 9.0 (RC1)
• Changed: Migrated Direct2D presentation system from DirectComposition to Windows.UI.Composition
• Fixed: Rotate/Zoom had really broken rendering with particular image sizes, such as 13830 x 7485 px (which was 4 tiles wide by 2 tiles tall)
• Known Issue: Title bars of dialog boxes will sometimes start out as white and then fade to black, instead of just being black (bug in .NET 9.0 RC1, already fixed for 9.0 RC2)
• Changed: Plugins may no longer use BinaryFormatter
• Updated the bundled AVIF FileType to version 3.10.0. Thanks @null54!
• Updated the bundled DDS FileType Plus to version 1.12.11. Thanks @null54

Download and Install

This build is available via the built-in updater as long as you have opted-in to pre-release updates. From within Settings -> Updates, enable “Also check for pre-release (beta) versions of paint.net” and then click on the Check Now button. You can also use the links below to download an offline installer or portable ZIP.

You can also download the installer here (for any supported CPU and OS), which is also where you can find downloads for offline installers, portable ZIPs, and deployable MSIs.