3230cf99f9
This provides a reduction from 26 to 18 constraints for trilinear and from 162 to 75 for quadratic. The assembly of the constraints becomes trivial. In total the speedup for a trilinear 3x3x3 grid is about 3x. PiperOrigin-RevId: 902502398 Change-Id: I764772c7adef78da5a644f64701f842d36e4b543