Image editor (save/load supported!)
IMPORTANT: Please post image codes (especially big ones) in the forum thread at https://scratch.mit.edu/discuss/topic/32129/ -- comments on this project might not let you post the whole thing!
Before you can do anything, you need create a new image (or load one that you have already). You can use the "File" menu at the top of the stage to create, save, load, and export images. Use the buttons on the left to switch tools, and click the color rectangle above them to change the drawing color.
The "Image" and "Filter" menus let you change the image in various ways.
Images with width greater 56 and/or height greater than 51 will be too big to fit on the stage.
When you save an image, you'll be given an "image code," which can be used to load your image into the project later.
The eraser tool creates transparent pixels.
While setting the color, you can click on the numbers to change them directly.
B to switch to paintbrush
P to switch to color picker
E to switch to eraser
F to switch to bucket fill
S to switch to smudge
Shift + N to make a new image
Shift + S to save
Shift + L to load an image
For the ones that use shift, several other keys including alt and control will do the same thing.
Images can be exported as SVG, XPM, or BBCode. These formats can be used elsewhere, but can't be loaded back into this project.
SVG exporting is mainly useful if you want to use your image as a costume in a Scratch project, or if you just want it in a format that can be used by lots of programs.
XPM might be useful if you want your image to stay pixel-based, and don't mind if there aren't quite so many programs that can open it.
BBCode lets you post images in the forums using colored characters, but please don't use it to spam! It might be best to just put a small image in your signature.
Uses a few "hacked" blocks (for information about that, see https://wiki.scratch.mit.edu/wiki/JSON_Tutorial )
The forum thread for this project is https://scratch.mit.edu/discuss/topic/32129/
I have some pages about the image format used in this project at https://zatnik.github.io/zatnik-images/
Also maybe check out https://scratch.mit.edu/projects/158350887/ where you can turn 16x16 images from this project into Minecraft-style blocks
Or https://scratch.mit.edu/projects/208211604/ which turns an image into an actual Minecraft structure file
The block for detecting special keypresses is from a project by @griffpatch, and the RGB to HSV conversion algorithm came from rapidtables.com.