Is there any trick to dynamically color low-poly designs?

Question

I know the normal method is to fill the the areas with original color from the photo above which the triangles are residing. But I'm looking for an easy way to color them with random colors (all while maintaining the harmony ofcourse). In other words, inclusion of dynamic colors without disturbing the harmony if possible. The recolour option doesn't look so promising. I know one way is to manually fill every area as last resort. But anything other than that? I'm looking for something like these animals in these projects - https://www.behance.net/gallery/29670207/ADI-bank-Youth-Cards https://www.designcontest.com/blog/inspiration-gallery-low-poly-art/

Working with Affinity Designer and Adobe Illustrator.

Answer 1

They can be colored traditionally following a photo. Then the palette can be modified by using some rule or fully manually - that's the thing you consider not promising, but which surely will be the good way for an artist who already has imagined the result exactly.

A programmer can create his recoloring rules as scripts. Unfortunately I cannot give an example because I'm not a programmer. But I can give an example of rule based recoloring. In the following image every color has got hue and saturation shift

Rule based recolorings can be created also with blending modes:

Here the recoloring strength is controlled with a layer mask (opacity mask in Illustrator)

One more example. The top layer is a copy of the hue shifted version. It has blending mode multiply and the original hue shifted version has been transformed with a weird curve which inverts part of the midtones: