For more discussion and for the direct download link, head on over to the forum: https://forums.getpaint.net/topic/113153-paintnet-41-beta-build-6808/

I’ve been hard at work on this for the last 7 months and it’s finally time for a beta release! There’s a lot of small- and medium-size things all over the place There have been some significant performance improvements to some important effects, especially those in the Blur menu. There are also a lot of quality-of-life improvements, some great bug fixes, and the ability to perform copy and paste operations on the selection, among many other things. I’ve also been making a lot of improvements “under the hood” that won’t really be visible, but that will make it easier and faster for me to make progress on features and other performance improvements.

Thanks to @BoltBait and @toe_head2001 for their contributions in this release!

Here’s a quick overview of some of the bigger changes:

• GPU-powered Effects! Some of the effects have been rewritten to use Direct2D’s image processing system, and the results are phenomenal for performance. Gaussian Blur is actually fast now and no longer takes ages to complete for large images or radii, and the same goes for both Motion Blur and Radial Blur (although Radial Blur does currently need a pretty powerful GPU). A few other effects were converted for the sake of completeness and for my own learning, and there are two new ones (Morphology and Turbulence). This is where most of my time (the aforementioned “last 7 months”) and sweat was spent: getting a GPU-based effect rendering system up and running end-to-end was no small feat! Expect to see more effects converted over to the GPU in subsequent updates as this tech matures. I am also planning to make the GPU available for plugins to use in a future update.
  
• Copy/Paste for Selections. You can now copy the active selection to the clipboard, as well as paste from the clipboard to the active selection (all selection combine modes are supported). This copies only the selection, not the pixels that are within the selection. You can then apply the selection to another layer or image, or just save it for later. Because the selection is copied to the clipboard as JSON text, you can use external utilities to maintain them or even do processing on them (you aren’t limited to Paint.NET’s built-in selection operations, in other words). For example: if you want to save and reuse 5 selections, just open up 5 copies of Notepad and use them as a storage buffer. You can also use Paste Selection when a regular image is on the clipboard: if the image is from Paint.NET, the embedded selection will be used, otherwise the image’s size will be converted to a selection (a rectangle anchored to x=0,y=0 with the same width and height as the image). More formal documentation for the data format will be available soon.
  
• Bicubic resampling for the Move Selected Pixels tool. This can produce much higher quality results than Bilinear resampling. It is very CPU-intensive, so a fast CPU with 6+ cores is highly recommended if you plan to use it a lot. The default is still Bilinear, so if you’d prefer to always use Bicubic you can change it from Settings -> Tools.
  
• New +/- buttons for Tolerance and Hardness. This is a great quality-of-life improvement, especially for the Magic Wand when you’re trying to find just the right value for Tolerance.
  

Change log since 4.0.21:

• Improved: Gaussian Blur, Motion Blur, and Radial Blur now render using the GPU and are significantly faster
• Changed: The following effects are now rendered using the GPU: Edge Detect, Pixelate, and Relief
• Changed: The following adjustments are now rendered using the GPU: Black & White, Invert Colors
• New Effect: Distort -> Morphology (uses the GPU)
• New Effect: Render -> Turbulence (uses the GPU)
• New: Bicubic resampling is now supported for the Move Selected Pixels tool. It is very CPU-intensive, so a CPU with 6 or more cores is highly recommended.
• New: Edit -> Copy Selection. This will copy the current selection’s geometry to the clipboard as JSON text.
• New: Edit -> Paste Selection. This will apply the selection from the clipboard to the current selection. All 5 selection combine modes are supported.
• Changed: The Text tool now uses Points for font size measurement. You can also elect to use the old font size metric, “Fixed (96 DPI)” via the dropdown to the right of the font size.
• Fixed: The Text tool’s recentering algorithm when typing reaches the edge of the viewport should be better
• New: Added +/- buttons to the Tolerance and Hardness sliders.
• Changed: Increased max zoom level to 6400%
• New: The mouse wheel may now be used to scroll a long menu, such as when a lot of effects are installed (thanks @toe_head2001!)
• Changed: For Windows 7 SP1 users, the Platform Update from 2013 is now required.
• Fixed: Opening certain large images and then zooming with the mouse wheel would sometimes result in the scroll position being completely wrong
• Changed: Hiding a layer no longer auto-selects the nearest visible layer. You can re-enable this in Settings
• New: For the Windows Store release, the paintdotnet: protocol can now be used to launch the app so that you can specify command-line parameters. For example, you can go to Start -> Run and type in paintdotnet:”path to file1.png” path_to_file_2.png and both images will be opened (even if Paint.NET is already open)
• New: Added Heptagon (7-sided polygon) and Octagon (8-sided polygon) shapes
• Fixed the high-DPI inset-text scaling for the Shape selector (e.g. Pentagon with an inset “5”)
• New: Palettes are now also loaded from Documents/paint.net App Files/Palettes. This folder name is not localized, and so is easy to rely on for installation scripts.
• Fixed: View -> Pixel Grid will now correctly adjust to changes in the theme (light vs. dark)
• Fixed: The background color for the Tolerance slider has been corrected for non-dark themes
• Changed: Removed shortcut keys for all built-in Adjustments except for Invert Colors (Ctrl+Shift+I). This is being done to free up shortcut keys for other functionality.
• New: Added a shortcut key to trigger a full .NET garbage collection: Ctrl+Alt+Shift+` (tick/tilde). This should only ever be needed for troubleshooting purposes.
• New: Battery Saver Mode in Windows 10 is now respected, whether enabled manually or due to low battery. UI animations will be disabled.
• New for plugin developers: The IndirectUI Color Wheel control now supports an alpha slider. To use this, set the range (min/max values) of the Int32PropertyControl to [Int32.MinValue, Int32.MaxValue] (thanks @BoltBait!)
• New for plugin developers: there is a new FileChooser property control type for string properties (thanks @toe_head2001!)
• New for plugin developers: there is a new BinaryPixelOp.Apply(Surface, Surface, Surface, Rectangle) method overload (thanks @BoltBait!)
• Changed: The IndirectUI text control now has a vertical scroll bar when multiline mode is enabled (thanks @toe_head2001!)
• Fixed a very old and nasty crash, “InvalidOperationException: ScratchSurface already borrowed”

Enjoy! Please comment with your questions and bug reports