void
GrainTracker::remapGrains()
{
// Don't remap grains if the current simulation step is before the specified tracking step
if (_t_step < _tracking_step)
return;
/**
* Loop over each grain and see if the bounding spheres of the current grain intersect with the spheres of any other grains
* represented by the same variable.
*/
unsigned times_through_loop = 0;
bool variables_remapped;
do
{
Moose::out << "Remap Loop: " << times_through_loop << std::endl;
variables_remapped = false;
for (std::map<unsigned int, UniqueGrain *>::iterator grain_it1 = _unique_grains.begin();
grain_it1 != _unique_grains.end(); ++grain_it1)
{
if (grain_it1->second->status == INACTIVE)
continue;
for (std::map<unsigned int, UniqueGrain *>::iterator grain_it2 = _unique_grains.begin();
grain_it2 != _unique_grains.end(); ++grain_it2)
{
// Don't compare a grain with itself and don't try to remap inactive grains
if (grain_it1 == grain_it2 || grain_it2->second->status == INACTIVE)
continue;
if (grain_it1->second->variable_idx == grain_it2->second->variable_idx && // Are the grains represented by the same variable?
boundingRegionDistance(grain_it1->second->sphere_ptrs, grain_it2->second->sphere_ptrs, false) < 0) // If so, do their spheres intersect?
{
// If so, remap one of them
swapSolutionValues(grain_it1, grain_it2, times_through_loop);
// Since something was remapped, we need to inspect all the grains again to make sure that previously ok grains
// aren't in some new nearly intersecting state. Setting this Boolean to true will trigger the loop again
variables_remapped = true;
// Since the current grain has just been remapped we don't want to loop over any more potential grains (the inner for loop)
break;
}
}
}
if (++times_through_loop >= 5 && processor_id() == 0)
mooseError(COLOR_RED << "Five passes through the remapping loop and grains are still being remapped, perhaps you need more op variables?" << COLOR_DEFAULT);
} while (variables_remapped);
Moose::out << "Done Remapping" << std::endl;
}
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;
}
