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Copy-paste your current colors.gml's file content in the text field on the right, and/or start defining {{colorspelling}}s.
Ranges are automatically calculated from the palette (it doesn't read them from the code.)
The text field will be updated in real time (and forced into this tool's format because it's easier for me, sorry!)
Copy-paste the code back into your colors.gml file once you're done.

Usage videos available here, here and here.
You can load a sprite to preview re{{colorspelling}}s (The tool is completely local, nothing gets uploaded anywhere.)
You can rename rows and slots by clicking on their name. This will update the header comment in the .gml file.
You can ctrl+c / ctrl+v a color as soon as you open it's picker.
The shading value input is purely to test out how that'll render, and will not be written to the gml code as a set_character_color_shading() line.

If you need help with animations hit/hurtboxes and attack scripts, check out RoABox!

Official doc about colors.gml here. Youtube video explanation here.
It uses TinyColor for parsing, so it should support all the correctly-formatted color formats you can throw at it.
Color picker heavily based on "a cool Color Picker with vue.js BY Florian Schulz."
Built with Vue.js.

{{ (autoMoveShades ? 'A' : 'Not a') + 'utomatically moving shades when palette rows are moved' }}
{{ (skipConfirmRecolor ? 'Not a' : 'A') + 'sking confirmation before recoloring big pictures' }}
U.K. mode 🇬🇧

- If you think a specific color in the range is being changed in an odd way (on desaturated shadows, for example), it'll happen in-game too. Might work to separate the range by that odd color on its own, if you have some free space left. This example is shown in the leftmost "usage video" as well.

- If some color range seem to be overlapping and the other range gets overwritten, it'll happen in-game too. Ranges later in the order will happen later, taking priority. Try to mess around with vertical order of the colors, if you're having trouble with it!

- New update some time ago added a bunch of function, among which is a function to "adjust" the amount of "shade" applied to the colors.
The function in question is set_character_color_shading( shade_slot, shading_value ). This function isn't put in colors.gml, so it won't be applied by this tool. However, you can preview the values!
You can read more about the function's usage elsewhere... hopefully?

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