Variable temperature inside the grid box

[cb LLC]

Hi We have rocks that are falling in lava. Closer they get to lava (bottom of the grid box) more they catch on fire. Anyway to have top part of grid box have lower temperature than lower part. That way they do not catch fire till they get closer to lava Thank you
we are using 2.2 version

[cb LLC]

UPDATE: we added gradient map to temperature slot. Problem is UVW gizmo travels with object unless you animate it to make it stationary but we will have 100s of rocks , Not sure if there is any way for gizmo to be stationary so rocks will be black on top (low temp) and more they travel whiter they get (high temp )

[cb LLC]

Ok we got it to work. So here is a trick there is a script called gizmolock it locks gizmo so when objects fall down they change color from black to white (and do not carry gizmo with them) therefore they go from smoking to catching fire by the time they reach the bottom. Hopefully this will help whoever needs it too. Not sure if there are proper ways to do it.