Unreal Material Simple gradient control

1. simple linear gradient

Linear gradient function is taking texture coordinate, masking out U(R) and V(G)

U gradient is from left to right

V gradient is from right to left

Here I'm using a Switch parameter node to switch between u gradient or v gradient.

Then multiply to a scalar parameter for direction. When using U gradient, this would allow us to switch between left and right. When using a V gradient, this would allow us to switch between up and down.

Then Subtracting the gradient to a scalar parameter would allow us to do the dissolve effect.

To make the transition more interesting, subtract a noise texture.

Quick Demo

2. Sphere gradient Control