The first alpha for paint.net 4.0 is now available! To download it, please head over to the forum: http://forums.getpaint.net/index.php?/topic/27227-paintnet-40-alpha-build-5034/
Please note that this is an alpha! It is mostly complete but there are bugs, both known and unknown. DO NOT install this if you depend on Paint.NET for your livelihood, for instance, as it might crash at seemingly random times or even corrupt your data (that’s actually very unlikely but, still, use caution). After alpha comes beta, and then final (general availability) or "RTW" (release to web) (also sometimes called RTM).
NOTE: The alpha is not available via the updater in v3.5.11, even if you have “Also check for pre-release (beta) versions” enabled. The beta for 4.0, however, will be made available through that update channel (from v3.5.11, I mean). I’m deliberately doing this in order to keep the audience size smaller for now so that my inbox doesn’t get flooded (I’m also not advertising it on the paint.net website just yet). Newer 4.0 alpha builds will, of course, be automatically offered to you once you have any 4.0 alpha installed.
Here is a list of the most prominent changes between v3.5.11 and 4.0:
- System requirements
- Windows 7 SP1 or newer is now required.
- Windows XP and Windows Vista are no longer supported (paint.net will not install).
- .NET Framework 4.5 is now required, and will be installed if needed.
- A dual-core (or more!) CPU is highly recommended. (I no longer test on single core systems, btw.)
- A brand new, asynchronous, fully multithreaded rendering engine
- Performance scales very well with respect to the number of CPU cores, whether you have 2, 4, 6, or even 16 of them.
- Performance scales much better with large, or even huge, images. Rendering will slow down and you will see tiles “trickling” in as they are completed, but the UI will still be responsive to your changes and clicks.
- The canvas now uses hardware acceleration via Direct2D, which also improves performance.
- Memory usage is lower.
- Selections have been improved in many ways
- Antialiased selections. You may turn this on/off at any time from the toolbar.
- Selection outlines are now rendered with the “dancing ants” animation.
- Performance of selection rendering and manipulation (Move Selection tool) have been fantastically improved.
- General UI
- The functionality previously provided by the Utilities, Window, and Help menus has been simplified, consolidated, and moved to the top-right corner of the main window.
- A brand new Settings dialog makes it much easier to configure all the tool and toolbar defaults, among other things.
- The zoom slider and units selector have been moved from the toolbar to the bottom right corner of the window (into the status bar).
- The image thumbnail list is now left-aligned and does not move around when you switch between certain tools.
- The image thumbnail list can now be reordered with drag-and-drop.
- Updated theming to a white, blue, flat motif.
- Tools
- Tools may now draw directly with a blending mode, configurable from the toolbar. All of the layer blending modes are supported, as well as “Overwrite.”
- Drawing tools (Pencil, Paintbrush, Eraser, Clone Stamp, Recolor) now have much smoother mouse input handling via GetMouseMovePointsEx.
- Brush tools (Paintbrush, Eraser, Clone Stamp, Recolor) now have soft brushes support via a “Hardness” setting in the toolbar.
- The Move tools (Move Selected Pixels, Move Selection) have a much better UI for scaling, moving, and (especially) rotation.
- Color Picker has a configurable sampling radius, and can sample from either the current layer or the whole image.
- Gradient tool now supports a new “Spiral” gradient type, and allows configuration of the repeat mode (none, repeat, wrapped).
- Magic Wand and Paint Bucket now allow live adjustment of Tolerance and the Origin (click location) after clicking (press Enter to commit/finish).
- Magic Wand and Paint Bucket can now sample from either the current layer or the whole image.
- The Paint Bucket now supports anti-aliasing.
- The Recolor tool can now use the color of the pixel where you click as the color to be replaced. Or, as usual, it can use the secondary color.
- The new Shapes tool replaces the Line/Curve, Rectangle, Rounded Rectangle, Ellipse, and Freeform shape tools. 29 shapes are currently available. You may move, resize, and rotate a shape, as well as reconfigure any other properties from the toolbar (color, outline size, etc.) before committing it to the layer.
- Miscellaneous
- Layers can now be reordered with drag-and-drop
- Edit –> Copy Merged
- Shift+Backspace will now fill the selection with the secondary color (Backspace fills with primary color, as usual)
- Ctrl+Click on the Move Layer Up/Down buttons will now move a layer to the top/bottom
- New exception/error dialog
- Improved battery life impact due to fixing the way the floating windows manage their transparency
- paint.net now shows up in the “Default Programs” control panel so you can configure its file type associations
- Improved performance of saving .PDN images
- Image->Resize has improved super sampling quality
paint.net blog 
First thing I noticed: shitty Spanish translations 😦
(I could lend a hand in that regard if you wanted me to).
Yup. The translations are now being handled by Bing machine translation. I’m hoping to get a way to incorporate human translation/feedback, I just don’t have anything set up for it yet.
Is it possible to install and run v4alpha alongside 3.5 ?
What’s up with the version number strategy? I thought that the point was to match the major/minor version numbers of the targeted framework. Shouldn’t this be Paint.NET 4.5? 🙂
Nope… when did I ever say that? 🙂
Sounds like little joke… 😀
Will installing this version replace my existing installation of 3.5.11 or can the two coexist?
So, I’ve found out what crashed it, it was MakeColourTrans.dll effect
Looks great so far.
Great! The most remarkable simplicity even seen in a desktop application combined with the powerful tools makes something common a revolutionary product 🙂
When is version 5.0?
Version 5?! I don’t know … the future?
I don’t want to make comparison to other products, but by observing Your forum, the 4.0 of a raster editor makes more excitement than a “s” or “c” version of a popular smartphone. (You unfortunately did not have rumors 😦 ).
By the way, by browsing the code structure of Your app, You didn’t add just new features, but rebuilt everything from the beginning.
Hope You read: http://en.wikipedia.org/wiki/Obfuscation_(software)
Windows Vista are no longer supported (paint.net will not install).
Whyyyyy??
I still use Vista at my home desktop. I hope you change your mind and still support Vista.
Sorry. This is not going to change.
Please..?
Nope.
I’m still using Vista as well. 😦 May I ask, what specifically is it in Vista that prevents v4.0 from running, as compared to Windows 7?
An updated copy of Vista (i.e. SP2 + Platform Update + Platform Update Supplement) is not all that different (feature or performance-wise) compared to Windows 7, and .NET 4.5 is supported on Vista as well. Dropping XP support is completely understandable, but why the unfortunate discrimination against Vista?
Hi Rick, another +1 for Vista support here. What do Win7/8 have that we don’t have access to? 🙂
Everything. And thus, Vista is incredibly slow and it’s old too. Also, .NET 4.5 is not supported on Vista.
Have you used Vista at all ever, or at least after SP1? Or are you just one of those who parrots what you read on the net? Try Vista with all the latest updates installed and then tell me how much faster Win7 is after an honest comparison. Also, .NET 4.5 is very much supported on Vista SP2, so get your facts straight before posting. Anyone who’s not on SP2 by now four and a half years after release doesn’t deserve to be on the internet in any case, leave alone deserve Paint.NET 4. 🙂 Thus my original question *still* remains unanswered – why is Vista omitted? If there are some APIs missing then that’s fine, but it would be nice if Rick can let us in on the secret.
Did you read this article about the new x64 .Net JIT Compiler? It name checks Paint.net as being a beneficiary of faster start up times: http://blogs.msdn.com/b/dotnet/archive/2013/09/30/ryujit-the-next-generation-jit-compiler.aspx
Nope, didn’t see that, but it sounds pretty cool
I’m running Win2k8 Server which I know is more Vista than Win7 but I’m wondering if WIn2k8 is an acceptable OS?
Nope. You’ll need Win2k8 R2.
V4 pretty much adds everything I need, so thank you for that Rick.
The one feature I miss from other paint apps is the use of the middle mouse button to pan-and-drag the image around. This is very handy when zoomed right into the pixels.
I know there’s the spacebar+left-mouse-button method, but as the documentation notes this does not work while typing with the text tool. And the scroll wheel combinations feel kinda clunky.
Using the middle mouse button could even replace all of the above methods.
That’s actually a fantastic idea, and I don’t know why I didn’t think of it before. I’ve filed a bug.
Will the future v4.0 support bulk processing of images (resize, etc.)?
Nope
Are plugins that work for 3.x (like Bulk Image Processor) compatible with 4.0 then?
Most plugins are compatible, I think.
I have a older version I think. 3.5, why caan´t I open the picture I do in Paint.net. If I open I come to paint.net agatin. I want the picture in my blog but it´s don.t take. it. Whya should I do the picture in Paint.net wwhen I can´t use them
I cant speak english, hope you understand what I mean.
Sorry but this blog isn’t a good place for troubleshooting. A better place for that is the forum, http://forums.getpaint.net/
.Net 4.5.1 went Gold! (http://support.microsoft.com/kb/2859818). Says increased performance.
Rick, is there a reason for not supporting rotations, saved in the meta data of images?
Implementation of such should be quite simple, I just remember using this for another project. And Windows 8 supports those, too 🙂
PS: Good work 🙂 !
Hi,
Is there an option in the Alpha, to support “Prefenceses” style personal settings. For example, I want to save default JPG files, not PNG files. Is this possible in the Alpha Release?
I’m getting a 404 error from the alpha build when checking for updates. I realize this probably affects little unless there’s an update at hand, but I wanted to report it.
I am impressed 🙂 hands down, this seems 1000x faster than the previous one, thank you so much for keeping it up! GREAT WORK
You’re welcome!
WOW! It runs so fast now, no matter the size of the image. Keep it up, man!
Is there support for tablet sensitivity now? I saw it mentioned before but I wasn’t sure if “Brush tools (Paintbrush, Eraser, Clone Stamp, Recolor) now have soft brushes support via a “Hardness” setting in the toolbar.” meant this?
IIRC it got removed some years ago and I don’t think there is yet timeline for its return.
(Incidentally after I ceased to use it…)
Dang, it was mentioned two blog posts ago (https://blog.getpaint.net/2013/03/30/paint-net-4-0-brushes-and-shapes-and-stuff/) and I thought perhaps it might’ve made it in. I was really looking forward to it because I just bought a tablet.
Now I’m going to have to find something else, aww well.
Any plans for a port to “modern ui” and perhaps ARM? It would quickly become really popular I think since there are no equivalents so far.
Excellent execution！I’m really impressed. I like the GPU accelerated feature, much needed performance boost as v3 are much slower compared to the bulky Photoshop. I like the new Shape tool too! The only thing missing is Magnetic Lasso, which I still rely on Photoshop.