I want to immediately notice that I googled and tried different solutions before coming up with a question here, but alas ... Maybe someone will tell you which way to dig or give advice on how to solve, the essence is as follows:
When I try to implement a gradient, not the essence of what type (linear, radial ...), the gradient itself for some reason is shown to be of very poor quality, i.e. there is no smooth transition from one color to another.
The code of the modules is laid out like a gist on the github: https://gist.github.com/SpaceMotion/fcdb8cd4e234b1d32afcd65b877d8dfe.
Thank you in advance!
I don't know why, but on real device system shows high quality gradient. Well, real user use real device, so the problem was gone in a magic way :)