JS Paint

A nice web-based MS Paint remake and more... Try it out!

The goal is to remake MS Paint (including its little-known features), improve on it, and to extend the types of images it can edit. So far, it does this pretty well.

Ah yes, good old paint. Not the one with the ribbons or the new skeuomorphic one with the interface that can take up nearly half the screen. And sorry, not the even newer Paint 3D.

Windows 95, 98, and XP were the golden years of paint. You had a tool box and a color box, a foreground color and a background color, and that was all you needed.

Things were simple.

But we want to undo more than three actions. We want to edit transparent images. We can't just keep using the old paint.

So that's why I'm making JS Paint. I want to bring good old paint into the modern era.

Current improvements include:

• Cross-platform
• Unlimited undos/redos (as opposed to a measly 3 in Windows XP, or a measly 50 in Windows 7)
• Autosaves a backup of your image. Only one backup tho, which is apparently not enough, because the browser may clear the canvas to free up memory, and you're likely to lose the backup when this happens because it gets overwritten. If this happens (canvas becomes a checkerboard), try to undo (a few times), and if that doesn't work, try to refresh the page. Remember to save with File > Save!
• Edit transparent images! To create a transparent image, go to Image > Attributes... and select Transparent, then Okay, and then Image > Clear Image or use the Eraser tool. Images with any translucent pixels will open in Transparent mode.
• Go to View > Extras Menu to enable access to additional features not available in MS Paint
• Switch themes from the Extras menu
• Create an animated GIF from the current document history. Accessible from the Extras menu or with Ctrl+Shift+G. It's pretty nifty, you should try it out! You might want to limit the size of the image though.
• You can shoot at it Asteroids style
• When you do Edit > Paste From... you can select transparent images. You can even paste a transparent animated GIF and then hold Shift while dragging the selection to smear it across the canvas while it animates! Update: This was due to not-to-spec behavior in Chrome. I may reimplement this in the future as I really liked this feature.
• You can open SVG files (because browsers support SVG). It's still a completely raster image editor though. (And you can't choose a size to render the SVG at. It may open super large, or tiny.)
• You can crop the image by making a selection while holding Ctrl
• Keyboard shortcuts for rotation: Ctrl+. and Ctrl+, (< and >)
• Rotate by any arbitrary angle in Image > Flip/Rotate
• In Image > Stretch/Skew, you can stretch more than 500% at once
• Zoom to an arbitrary scale in View > Zoom > Custom...
• Non-contiguous fill: Replace a color in the entire image by holding Shift when using the fill tool
• Rudimentary multi-user support. Start up a session at jspaint.app/#session:multi-user-test and send the link to your friends! It isn't seamless; actions by other users interrupt what you're doing, and visa versa. Sessions are not private, and you may lose your work at any time. If you want better collaboration support, follow the development of Mopaint.
• Load many different palette formats with Colors > Get Colors. (I made a library for this.)
• Mobile support (altho fairly lacking in some areas. it'd be nice if you could pan and zoom with two fingers)
• Click/tap the selected colors area to swap the foreground and background colors

Possible future improvements:

• Extended Editing
• Proportionally resize the selection or canvas by holding Shift (or maybe that should be the default, really!)
• Alt as a shortcut for the eyedropper, as long as it doesn't conflict with keyboard navigation of menus
• Optional fill tolerance (slider that you enable from a settings menu?)
• Interactive tutorial(s)?

Limitations:

A lot of stuff isn't done yet. See: the big long todo list.

Full clipboard support in the web app requires a browser supporting the Async Clipboard API w/ Images, namely Chrome 76+ at the time of writing.

In other browsers you can still can copy with Ctrl+C, cut with Ctrl+X, and paste with Ctrl+V, but data copied from JS Paint can only be pasted into other instances of JS Paint. External images can be pasted in.

There's also a desktop app version you can install that has full clipboard support,
which also lets you set the wallpaper.

Extended Editing

I want to make JS Paint to be able to edit...

• Transparent PNGs - Done! Images that are partially transparent will automatically open in Transparent mode. To enable transparency for an image, go to Image > Attributes... or press Ctrl+E, select Transparent, and hit Okay. Then you'll want to remove some of the background. You can use the Eraser tool a bit, then use the Color Picker to pick up where you erased and then use the Fill tool to remove bigger areas.
• Animated GIFs (yes, that entails a fully featured (but simple) animation editor). - Currently you can only make GIFs of the document history, with Ctrl+Shift+G or from the Extras menu.
• Animated Transparent APNGs (better than GIFs, but with less support)
• Multi-size Icons (ICO for windows and ICNS for mac)
• Scalable Vector Graphics (kidding) - Actually, it could always open SVG files in browsers that can handle SVGs, and I've made it try not to save over the original SVG. That's pretty decent SVG support for a 100% raster image editor.
• Text files (definitely just kidding maybe)
• Tessellating patterns, and textures on 3D models; that might be a pipe dream, but then again... hm...

Did you know?

• There's a black and white mode with patterns instead of colors in the palette, which you can get to from Image > Attributes...

• You can drag the color box and tool box around if you grab them by the right place. You can even drag them out into little windows. You can dock the windows back to the side by double-clicking on their title bars.

• In addition to the left-click foreground color and the right-click background color, there's a third color you can access by holding Ctrl while you draw. It starts out with no color so you'll need to hold Ctrl and select a color first. The fancy thing about this color slot is you can press and release Ctrl to switch colors while drawing.

• You can apply image transformations like Flip/Rotate, Stretch/Skew or Invert (in the Image menu) either to the whole image or to a selection. Try scribbling with the Free-Form Select tool and then doing Image > Invert

• These Tips and Tricks from a tutorial for MS Paint also work in JS Paint:

  • Brush Scaling (+ & - on the Numpad to adjust brush size)
  • "Custom Brushes" (hold Shift and drag the selection to smear it)
  • The 'Stamp' "Tool" (hold Shift and click the selection to stamp it)
  • Image Scaling (+ & - on the Numpad to scale the selection by factors of 2)
  • Color Replacement (right mouse button with Eraser to selectively replace the foreground color with the background color)
  • The Grid (Ctrl+G & Zoom to 4x+)
  • Quick Undo (Pressing a second mouse button cancels the action you were performing. I also made it redoable, in case you do it by accident!)
  • Scroll Wheel Bug (Hmm, let's maybe not recreate this?)

Desktop App

I've started work on a desktop app, built with Electron and Electron Forge.

There are no releases yet, but the groundwork has been laid, and several features implemented.

If you want to help out, see Development Setup below, and comment on this issue to show your interest.

Development Setup

Clone the repo.

Install Node.js if you don't have it, then open up a command prompt / terminal in the project directory.

Web App (https://jspaint.app)

You just need an HTTP server.

Live Server is great; it auto reloads when you save changes.

You can install it globally with npm i -g live-server and run it with live-server

It's also included in package.json so if you've already installed dependencies (npm i) you can use npm run dev to run it.

Desktop App (Electron)

• Install dependencies with npm i
• Start the electron app with npm start

electron-debug and devtron are included, so you can use Ctrl+R to reload and F12/Ctrl+Shift+I to open the devtools, and there's a Devtron tab with tools specific to Electron like an IPC message inspector.

You can build for production with npm run make