bool
GrainTracker::attemptGrainRenumber(MooseSharedPointer<FeatureData> grain, unsigned int grain_id, unsigned int depth, unsigned int max)
{
// End the recursion of our breadth first search
if (depth > max)
return false;
unsigned int curr_var_idx = grain->_var_idx;
std::map<Node *, CacheValues> cache;
std::vector<std::list<GrainDistance> > min_distances(_vars.size());
/**
* We have two grains that are getting close represented by the same order parameter.
* We need to map to the variable whose closest grain to this one is furthest away by sphere to sphere distance.
*/
computeMinDistancesFromGrain(grain, min_distances);
/**
* We have a vector of the distances to the closest grains represented by each of our variables. We just need to pick
* a suitable grain to replace with. We will start with the maximum of this this list: (max of the mins), but will settle
* for next to largest and so forth as we make more attempts at remapping grains. This is a graph coloring problem so
* more work will be required to optimize this process.
*
* Note: We don't have an explicit check here to avoid remapping a variable to itself. This is unnecessary since the
* min_distance of a variable is explicitly set up above.
*/
std::sort(min_distances.begin(), min_distances.end(), GrainDistanceSorter());
_console << "\n********************************************\nDistances list for grain " << grain_id << '\n';
for (unsigned int i = 0; i < min_distances.size(); ++i)
{
for (std::list<GrainDistance>::iterator min_it = min_distances[i].begin(); min_it != min_distances[i].end(); ++min_it)
_console << min_it->_distance << ": " << min_it->_grain_id << ": " << min_it->_var_index << '\n';
_console << '\n';
}
for (unsigned int i = 0; i < min_distances.size(); ++i)
{
std::list<GrainDistance>::const_iterator target_it = min_distances[i].begin();
if (target_it == min_distances[i].end())
continue;
// If the distance is positive we can just remap and be done
if (target_it->_distance > 0)
{
Moose::out
<< COLOR_GREEN
<< "- Depth " << depth << ": Remapping grain #" << grain_id << " from variable index " << curr_var_idx
<< " to " << target_it->_var_index << " whose closest grain (#" << target_it->_grain_id
<< ") is at a distance of " << target_it->_distance << "\n"
<< COLOR_DEFAULT;
swapSolutionValues(grain, target_it->_var_index, cache, BYPASS, depth);
return true;
}
// If the distance isn't positive we just need to make sure that none of the grains represented by the
// target variable index would intersect this one if we were to remap
std::list<GrainDistance>::const_iterator next_target_it = target_it;
bool intersection_hit = false;
std::ostringstream oss;
while (!intersection_hit && next_target_it != min_distances[i].end())
{
if (next_target_it->_distance > 0)
break;
mooseAssert(_unique_grains.find(next_target_it->_grain_id) != _unique_grains.end(), "Error in indexing target grain in attemptGrainRenumber");
MooseSharedPointer<FeatureData> next_target_grain = _unique_grains[next_target_it->_grain_id];
// If any grains touch we're done here
if (setsIntersect(grain->_halo_ids.begin(), grain->_halo_ids.end(),
next_target_grain->_halo_ids.begin(), next_target_grain->_halo_ids.end()))
intersection_hit = true;
else
oss << " #" << next_target_it->_grain_id;
++next_target_it;
}
if (!intersection_hit)
{
Moose::out
<< COLOR_GREEN
<< "- Depth " << depth << ": Remapping grain #" << grain_id << " from variable index " << curr_var_idx
<< " to " << target_it->_var_index << " whose closest grain(s):" << oss.str()
<< " are inside our bounding sphere but whose halo(s) are not touching.\n"
<< COLOR_DEFAULT;
swapSolutionValues(grain, target_it->_var_index, cache, BYPASS, depth);
return true;
}
// If we reach this part of the loop, there is no simple renumbering that can be done.
mooseAssert(_unique_grains.find(target_it->_grain_id) != _unique_grains.end(), "Error in indexing target grain in attemptGrainRenumber");
MooseSharedPointer<FeatureData> target_grain = _unique_grains[target_it->_grain_id];
// Make sure this grain isn't marked. If it is, we can't recurse here
if (target_grain->_merged)
return false;
// Save the solution values in case we overright them during recursion
swapSolutionValues(grain, target_it->_var_index, cache, FILL, depth);
// TODO: Make sure this distance is -1 or higher or fine intersections only exist for a single variable
// Propose a new variable index for the current grain and recurse
grain->_var_idx = target_it->_var_index;
grain->_merged = true;
if (attemptGrainRenumber(target_grain, target_it->_grain_id, depth+1, max))
{
// SUCCESS!
Moose::out
<< COLOR_GREEN
<< "- Depth " << depth << ": Remapping grain #" << grain_id << " from variable index " << curr_var_idx
<< " to " << target_it->_var_index << '\n'
<< COLOR_DEFAULT;
// NOTE: swapSolutionValues currently reads the current variable index off the grain. We need to set
// back here before calling this method.
grain->_var_idx = curr_var_idx;
swapSolutionValues(grain, target_it->_var_index, cache, USE, depth);
return true;
}
else
// Need to set our var index back after failed recursive step
grain->_var_idx = curr_var_idx;
// Always "unmark" the grain after the recursion so it can be used by other remap operations
grain->_merged = false;
}
return false;
}
void
GrainTracker::swapSolutionValues(std::map<unsigned int, UniqueGrain *>::iterator & grain_it1,
std::map<unsigned int, UniqueGrain *>::iterator & grain_it2,
unsigned int attempt_number)
{
NumericVector<Real> & solution = _nl.solution();
NumericVector<Real> & solution_old = _nl.solutionOld();
NumericVector<Real> & solution_older = _nl.solutionOlder();
unsigned int curr_var_idx = grain_it1->second->variable_idx;
/**
* We have two grains that are getting close represented by the same order parameter.
* We need to map to the variable whose closest grain to this one is furthest away by sphere to sphere distance.
*/
std::vector<Real> min_distances(_vars.size(), std::numeric_limits<Real>::max());
// Make sure that we don't attempt to remap to the same variable
min_distances[curr_var_idx] = -std::numeric_limits<Real>::max();
for (std::map<unsigned int, UniqueGrain *>::iterator grain_it3 = _unique_grains.begin();
grain_it3 != _unique_grains.end(); ++grain_it3)
{
if (grain_it3->second->status == INACTIVE || grain_it3->second->variable_idx == curr_var_idx)
continue;
unsigned int potential_var_idx = grain_it3->second->variable_idx;
Real curr_bounding_sphere_diff = boundingRegionDistance(grain_it1->second->sphere_ptrs, grain_it3->second->sphere_ptrs, false);
if (curr_bounding_sphere_diff < min_distances[potential_var_idx])
min_distances[potential_var_idx] = curr_bounding_sphere_diff;
}
/**
* We have a vector of the distances to the closest grains represented by each of our variables. We just need to pick
* a suitable grain to replace with. We will start with the maximum of this this list: (max of the mins), but will settle
* for next to largest and so forth as we make more attempts at remapping grains. This is a graph coloring problem so
* more work will be required to optimize this process.
* Note: We don't have an explicit check here to avoid remapping a variable to itself. This is unecessary since the
* min_distance of a variable is explicitly set up above.
*/
unsigned int nth_largest_idx = min_distances.size() - attempt_number - 1;
// nth element destroys the original array so we need to copy it first
std::vector<Real> min_distances_copy(min_distances);
std::nth_element(min_distances_copy.begin(), min_distances_copy.end()+nth_largest_idx, min_distances_copy.end());
// Now find the location of the nth element in the original vector
unsigned int new_variable_idx = std::distance(min_distances.begin(),
std::find(min_distances.begin(),
min_distances.end(),
min_distances_copy[nth_largest_idx]));
Moose::out
<< COLOR_YELLOW
<< "Grain #: " << grain_it1->first << " intersects Grain #: " << grain_it2->first
<< " (variable index: " << grain_it1->second->variable_idx << ")\n"
<< COLOR_DEFAULT;
if (min_distances[new_variable_idx] < 0)
{
Moose::out
<< COLOR_YELLOW
<< "*****************************************************************************************************\n"
<< "Warning: No suitable variable found for remapping. Will attempt to remap in next loop if necessary...\n"
<< "*****************************************************************************************************\n"
<< COLOR_DEFAULT;
return;
}
Moose::out
<< COLOR_GREEN
<< "Remapping to: " << new_variable_idx << " whose closest grain is at a distance of " << min_distances[new_variable_idx] << "\n"
<< COLOR_DEFAULT;
MeshBase & mesh = _mesh.getMesh();
// Remap the grain
std::set<Node *> updated_nodes_tmp; // Used only in the elemental case
for (std::set<dof_id_type>::const_iterator entity_it = grain_it1->second->entities_ptr->begin();
entity_it != grain_it1->second->entities_ptr->end(); ++entity_it)
{
if (_is_elemental)
{
Elem *elem = mesh.query_elem(*entity_it);
if (!elem)
continue;
for (unsigned int i=0; i < elem->n_nodes(); ++i)
{
Node *curr_node = elem->get_node(i);
if (updated_nodes_tmp.find(curr_node) == updated_nodes_tmp.end())
{
updated_nodes_tmp.insert(curr_node); // cache this node so we don't attempt to remap it again within this loop
swapSolutionValuesHelper(curr_node, curr_var_idx, new_variable_idx, solution, solution_old, solution_older);
}
}
}
else
swapSolutionValuesHelper(mesh.query_node_ptr(*entity_it), curr_var_idx, new_variable_idx, solution, solution_old, solution_older);
}
// Update the variable index in the unique grain datastructure
grain_it1->second->variable_idx = new_variable_idx;
// Close all of the solution vectors
solution.close();
solution_old.close();
solution_older.close();
_fe_problem.getNonlinearSystem().sys().update();
}