Start devel of native support for KIM simulator models

* CMake change to use KIM-API SimulatorModels branch
* Minimal changes to pair_kim to illustrate use of KIM API
  interface. Only c++ interface is implemented for development.
* Added example input: in.kim.simulator-model

cmake/CMakeLists.txt

@@ -738,8 +738,10 @@ if(PKG_KIM)
     enable_language(Fortran)
     include(ExternalProject)
     ExternalProject_Add(kim_build
-      URL https://s3.openkim.org/kim-api/kim-api-2.0.2.txz
-      URL_MD5 537d9c0abd30f85b875ebb584f9143fa
+      GIT_REPOSITORY https://github.com/openkim/kim-api.git
+      GIT_TAG SimulatorModels
+      #URL https://s3.openkim.org/kim-api/kim-api-2.0.2.txz
+      #URL_MD5 537d9c0abd30f85b875ebb584f9143fa
       BINARY_DIR build
       CMAKE_ARGS -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
                  -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}

examples/kim/in.kim.simulator-model

@@ -0,0 +1,41 @@
+# 3d Lennard-Jones melt
+#
+# This example requires that the example models provided with
+# the kim-api package are installed.  see the ./lib/kim/README or
+# ./lib/kim/Install.py files for details on how to install these
+# example models.
+#
+
+variable	x index 1
+variable	y index 1
+variable	z index 1
+
+variable	xx equal 20*$x
+variable	yy equal 20*$y
+variable	zz equal 20*$z
+
+units		metal
+atom_style	atomic
+newton          off
+
+lattice		fcc 4.4300
+region		box block 0 ${xx} 0 ${yy} 0 ${zz}
+create_box	1 box
+create_atoms	1 box
+
+#pair_style	lj/cut 8.1500
+#pair_coeff	1 1 0.0104 3.4000
+
+pair_style      kim ex_sim_model_Si_mod_tersoff
+pair_coeff      * * Ar
+
+mass		1 39.95
+velocity	all create 200.0 232345 loop geom
+
+neighbor	0.3 bin
+neigh_modify	delay 0 every 1 check yes
+
+fix		1 all nve
+#fix		1 all npt temp 1.0 1.0 1.0 iso 1.0 1.0 3.0
+
+run 		100

src/KIM/pair_kim.cpp

@@ -87,6 +87,7 @@ PairKIM::PairKIM(LAMMPS *lmp) :
    chargeUnit(KIM_CHARGE_UNIT_unused),
    temperatureUnit(KIM_TEMPERATURE_UNIT_unused),
    timeUnit(KIM_TIME_UNIT_unused),
+   simulatorModel(NULL),
    pkim(NULL),
    pargs(NULL),
    kim_model_support_for_energy(KIM_SUPPORT_STATUS_notSupported),
@@ -396,8 +397,10 @@ void PairKIM::coeff(int narg, char **arg)
 
    // Assume all species arguments are valid
    // errors will be detected by below
+   std::string atom_type_sym_list;
    lmps_num_unique_elements = 0;
    for (i = 2; i < narg; i++) {
+     atom_type_sym_list += std::string(" ") + arg[i];
      for (j = 0; j < lmps_num_unique_elements; j++)
        if (strcmp(arg[i],lmps_unique_elements[j]) == 0) break;
      lmps_map_species_to_unique[i-1] = j;
@@ -422,6 +425,15 @@ void PairKIM::coeff(int narg, char **arg)
 
    if (count == 0) error->all(FLERR,"Incorrect args for pair coefficients");
 
+   if (simulatorModel)
+   {
+     simulatorModel->AddTemplateMap("atom-type-sym-list", atom_type_sym_list);
+     simulatorModel->CloseTemplateMap();
+
+     error->all(FLERR,(simulatorModel->ToString()).c_str());
+   }
+   else
+   {
    // setup mapping between LAMMPS unique elements and KIM species codes
    if (kim_particle_codes_ok)
    {
@@ -449,6 +461,7 @@ void PairKIM::coeff(int narg, char **arg)
         error->all(FLERR, msg.str().c_str());
       }
    }
+   }
 
    return;
 }
@@ -770,7 +783,13 @@ void PairKIM::kim_init()
        &requestedUnitsAccepted,
        &pkim);
    if (kimerror)
-     error->all(FLERR,"KIM ModelCreate failed");
+   {
+     kimerror = KIM::SimulatorModel::Create(kim_modelname,&simulatorModel);
+     if (kimerror)
+       error->all(FLERR,"KIM ModelCreate failed");
+     else
+       return;
+   }
    else {
      if (!requestedUnitsAccepted) {
        error->all(FLERR,"KIM Model did not accept the requested unit system");

src/KIM/pair_kim.h

@@ -68,6 +68,7 @@ class KIM_API_model;
 extern "C" {
 #include "KIM_SimulatorHeaders.h"
 }
+#include "KIM_SimulatorModel.hpp"
 #include <sstream>
 
 
@@ -121,6 +122,7 @@ namespace LAMMPS_NS {
       KIM_TemperatureUnit temperatureUnit;
       KIM_TimeUnit timeUnit;
 
+      KIM::SimulatorModel * simulatorModel;
       KIM_Model * pkim;
       KIM_ComputeArguments * pargs;