2.X Planned Hair Root->Tip Color Rolloff Only works in one direction.

[Captain Varghoss]

Basically, it seems like the way it blends the colors is not the same depending on the lightness/darkness of the colors chosen, making accurate results hit or miss at best.

To reproduce, use any medium to long length hair (past shoulders) to see greater variation.
Choose white for the root color and black for the tip color, slide the rolloff slider to see expected results.

Now use black for the root color and white as the tip color. Results expected (to me) would be the exact opposite of the previous test. Instead it seems to blend the entirety or the hair from one to the other.

 

[meshedvr]

For whatever reason the root to tip rolloff is not linear (this is code I adopted for VaM usage). It uses a pretty odd power of 2 function to determine the rolloff using that factor setting. I can sort of see why as with typical hair you can have a strong root color that rolls off pretty quick well before the tip. If it used a linear blend function this wouldn't be possible.

I won't be changing this for 1.X as it would mess up everyone's existing hair coloring. I'll rework this for 2.X to allow an editable curve to specify how the color rolloff should work. There are some other places where custom curves would work better as well.

Also moving this to suggestions as it isn't really a bug. It is just how it works.