/* ~~~ FUNCTION (public) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* This function computes the route to the next vertex to explore.
*
* INPUTS:
* currentVertex - The current vertex in the maze.
*
* OUTPUTS:
* outputRoute - This will be populated with a fastest route from the current vertex to the next
* vertex to explore.
*
* RETURNS:
* A boolean value.
* If true then there remain vertices to explore and outputRoute is outputted as above.
* If false then there are no more vertices to explore and outputRoute is set to empty.
*
*/
bool CMazeMapper::ComputeNextVertex(const int& currentVertex, std::vector<int>& outputRoute)
{
DEBUG_METHOD();
// Generate graph from the CMap
// TODO: Fix this when you now how you will generate the graph / receive the map
vector< vector<double> > distanceMatrix;
vector<int> vertexLabels;
CGraph currentGraph { distanceMatrix, vertexLabels };
// Check there remain vertices to explore
if (m_vertsToExplore.size() > 0)
return false;
// Find closest of the vertices left to explore
int nextVertex { m_vertsToExplore[0] };
double currentFastestDist = currentGraph.ShortestDistance(currentVertex, m_vertsToExplore[0], true, outputRoute);
for (unsigned int i = 1; i < m_vertsToExplore.size(); ++i)
{
vector<int> newOutputRoute;
double newDist = currentGraph.ShortestDistance(currentVertex, m_vertsToExplore[i], true, newOutputRoute);
if (newDist < currentFastestDist)
{
currentFastestDist = newDist;
outputRoute = newOutputRoute;
nextVertex = m_vertsToExplore[i];
}
else if (newDist == currentFastestDist
&& VertexScore(m_vertsToExplore[i]) < VertexScore(nextVertex))
{
// If there is a tie in distances, choose the one which is closest to the bottom left of the maze
// If this is also a tie then do not update nextVertex. This is equivalent to choosing the vertex
// which is closer to the top left.
outputRoute = newOutputRoute;
nextVertex = m_vertsToExplore[i];
}
}
return true;
}
