GitLab

of just 1.  Backwards compatibility is provided by making the 2nd force constant
default to -1, which is reinterpreted as "copy the first force constant".

Updates both the reference and CUDA kernels.

Converted the array containing atom block indices for the neighbor list from ushort2 to int.  This removes the hard limit of 2 million atoms.

When converting to fixed point, multiply by 0x100000000 instead of 0xFFFFFFFF.  This should be (very very slightly) more accurate, since its reciprocal can be exactly represented in floating point.

Simple fix to combining rules allowing AMOEBA VdW parameters to be zero.  Zero parameter excludes all interactions involving that particle, in agreement with TINKER.

Commented out some minor optimizations in AMOEBA that were making the forces incorrect.  AMOEBA energies and forces now agree with TINKER to within 1e-9 (fractional energy) 1e-5 (fractional RMS force error) for NPT simulations on rectangular water boxes with PME and direct or mutual polarizability.

Modified calculateElectrostaticPotentialForAtomGridPoint_kernel to apply periodic boundary conditions
Unit test for multipole grid potential changed to system comprised of 216 water molecules; 
Tinker potential values now based on PBC

Refactored code for calculating system multipole moments and multipole potential on a grid
to separate files (removed from kCalculateAmoebaCudaRotateFrame.cu and kCalculateAmoebaCudaElectrostatic.cu)

Added new tests to TestCudaAmoebaVdwForce; fixed bug in AmoebaVdw tapering; non-default AmoebaVdw rules for calculating combinded epsilon 
value changed to agree w/ TINKER

Added AmoebaMultipoleForce::getSystemMultipoleMoments() to get system multipole moments; based on TINKER subroutine moments()

fixed problem w/ storage of PME induced dipoles