Redistributing modified assets from the base game

[SyncViews]

Am I allowed to create and distribute a mod by modifying existing Factorio content (e.g. a new item by taking sprites from data/base/graphics/ and recolouring it for say a new fluid), and is the terms and conditions for doing so formally documented somewhere?

[DaveMcW]

Yes it's allowed. No it's not formally documented. viewtopic.php?p=49122#p49122

[bobingabout]

I read the question, my answer is... Well, it better be! I've been doing it for years!!!
I even re-introduce old icons sometimes.

[prg]

If you just want to recolor an entity without changing the graphics otherwise, you can just add something like tint = {r=1.0, g=0.8, b=0.0, a=1.0} next to the relevant filename in the prototype definition.

This doesn't seem to work for icons though, you still need to copy and recolor them manually.

[bobingabout]

Although that works, the entire entity is recoloured.

what I did for some of them was create a mask to recolour only part of it.