/// <summary>
/// Check a neighbour of the current node to see if it needs to be added to the tentative list
/// or the shortest route to it needs to be updated.
/// </summary>
/// <param name="neighbour">The neighbour to check.</param>
/// <param name="current">The current node.</param>
/// <param name="dist">The distance from the root to the current node.</param>
/// <param name="link">The link between current and neighbour.</param>
private void checkNeighbour(DijkstraNode neighbour, DijkstraNode current, float dist, IMLink link)
{
float newDistance = dist + link.Weight;
try {
//If the new route from root to neighbour is shorter than the old route or there was no old route
//set the current node as the first step towards the root from neighbour
if (_cont && !_tentative.Contains(neighbour))
{
_tentative.AddFirst(neighbour);
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
}
else if (_cont && newDistance <= neighbour.GetDistanceFromRoot(ID))
{
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
}
} catch (KeyNotFoundException e) {
//If the AddLink being checked is no Keyer in the list of links the algorithm needs to stop
_cont = false;
if (_visualise)
{
VisualisedNode = null;
}
Logger.Debug("Trying to work with a neighbour (" + neighbour.Name + ") which is not actually connected to " +
current.Name + " (root = " + Name + ")");
}
//Incase another thread has modified the distance
if (_cont && newDistance < neighbour.GetDistanceFromRoot(ID))
{
neighbour.SetDistanceFromRoot(ID, newDistance, neighbour, link);
}
}
/// <summary>
/// The main loop which is the body of the algorithm.
/// Loops through every neighbour of the current node checking to see if they:
/// A. Have been visited before
/// B. Have been visited before but are now a shorter route
/// </summary>
/// <param name="current">The node currently being checked.</param>
/// <param name="prev">The previous node that was checked.</param>
/// <returns>The last node to be checked.</returns>
private void MainLoop(DijkstraNode current, DijkstraNode prev)
{
while (_cont && current != null && !hitTarget(current))
{
//If necessary display text and wait
if (_cont && _text && _visualise)
{
current.Say("4. Iterating through neighbours excluding neighbours in Confirmed");
Pause();
}
//Get the current distance to the target
float dist = current.GetDistanceFromRoot(ID);
foreach (var n in current.Neighbours)
{
IMLink link = current.Links[n.ID];
if (_visualise)
{
_links.AddFirst(link);
}
var neighbour = this.GetAlgNode <DijkstraNode>(n.ID);
if (_cont && !_confirmed.Contains(neighbour))
{
if (_visualise && _text)
{
VisualiseCheckNeighbourText(neighbour, current, dist, link);
}
else if (_visualise)
{
VisualiseCheckNeighbour(neighbour, current, dist, link);
}
checkNeighbour(neighbour, current, dist, link);
}
if (!_cont)
{
break;
}
}
//Store the old previous node
prev = current;
if (_cont && _text && _visualise)
{
Say("Finished iterating through current's (" + current.Name +
"'s) neighbours, getting next current from tentative list");
Pause();
}
//Get the next node to be checked (the one which has the shortest path to it)
current = getNext(current);
}
FinishedReset(current, prev);
}
/// <summary>
/// Visualise the process of choosing the next node. Will output text about what is going on if necessary.
/// </summary>
/// <param name="next">The next node to be current.</param>
/// <param name="prev">The node that was previously current.</param>
private void VisualiseChooseNext(DijkstraNode next, DijkstraNode prev)
{
if (_cont && !next.Equals(this))
{
if (_cont && _text)
{
Say("8. There are nodes in the tentative list. Finding the node in tentative with the smallest cost");
Pause();
}
Pause(3f);
if (_cont && _text)
{
Say("9. new current = " + next.Name + " with cost " + next.GetDistanceFromRoot(ID));
Pause();
Say("10. Adding link between ct (" + prev.Name + ") and new current (" + next.Name + ") to the shortest path");
Pause();
}
}
prev.Reset();
IMLink confirmedLink = next.GetWIPRoute(ID);
if (_cont && confirmedLink != null)
{
Pause(6f);
confirmedLink.Colour = Color.Red;
}
if (_cont && _text)
{
Say((next.Equals(this) ? "2a" : "11a") + ". Adding " +
(next.Equals(this) ? "root" : "new current") + " (" + next.Name + ") to Confirmed");
Pause();
Say((next.Equals(this) ? "2b" : "11b") + ". Setting current to " +
(next.Equals(this) ? "root" : "new current") + " (" + next.Name + ")");
}
next.Reset();
next.Selected = currentGlow;
next.Colour = Color.White;
if (_cont && _text && !next.Equals(this))
{
Pause();
Say("11c. Going to step 4");
Pause();
}
}
/// <summary>
/// Visualise the process of choosing the next node. Will output text about what is going on if necessary.
/// </summary>
/// <param name="next">The next node to be current.</param>
/// <param name="prev">The node that was previously current.</param>
private void VisualiseChooseNext(DijkstraNode next, DijkstraNode prev)
{
if (_cont && !next.Equals(this)) {
if (_cont && _text) {
Say("8. There are nodes in the tentative list. Finding the node in tentative with the smallest cost");
Pause();
}
Pause(3f);
if (_cont && _text) {
Say("9. new current = " + next.Name + " with cost " + next.GetDistanceFromRoot(ID));
Pause();
Say("10. Adding link between ct (" + prev.Name + ") and new current (" + next.Name + ") to the shortest path");
Pause();
}
}
prev.Reset();
IMLink confirmedLink = next.GetWIPRoute(ID);
if (_cont && confirmedLink != null) {
Pause(6f);
confirmedLink.Colour = Color.Red;
}
if (_cont && _text) {
Say((next.Equals(this) ? "2a" : "11a") + ". Adding " +
(next.Equals(this) ? "root" : "new current") + " (" + next.Name + ") to Confirmed");
Pause();
Say((next.Equals(this) ? "2b" : "11b") + ". Setting current to " +
(next.Equals(this) ? "root" : "new current") + " (" + next.Name + ")");
}
next.Reset();
next.Selected = currentGlow;
next.Colour = Color.White;
if (_cont && _text && !next.Equals(this)) {
Pause();
Say("11c. Going to step 4");
Pause();
}
}
/// <summary>
/// Visualises the process of checking a neighbour node and prints out text explaining what is happening.
/// </summary>
/// <param name="neighbour">The neighbour to check.</param>
/// <param name="current">The current node.</param>
/// <param name="dist">The distance from the root to the current node.</param>
/// <param name="link">The link between current and neighbour.</param>
private void VisualiseCheckNeighbourText(DijkstraNode neighbour, DijkstraNode current, float dist, IMLink link)
{
if (!_visualise && !_text)
return;
float newDistance = dist + link.Weight;
if (_cont) {
//if (_cont && _text)
// current.Say("Examining neighbour " + neighbour.Name);
Pause(4f);
link.Colour = Color.Blue;
if (_cont && _text) {
Pause();
current.Say("5. Test cost to " + neighbour.Name + " = " + dist + " + " + link.Weight + " = " +
newDistance);
Pause();
}
Pause(4f);
}
try {
if (_cont && !_tentative.Contains(neighbour)) {
if (_cont && _text)
current.Say(neighbour.Name + " is not in tentative list");
_tentative.AddFirst(neighbour);
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
if (_cont) {
Pause(4f);
neighbour.Selected = tentativeGlow;
if (_cont && _text) {
current.Say("6a. Adding " + neighbour.Name + " to the tentative list");
Pause();
current.Say("6b. " + neighbour.Name + ".cost = test cost (" + newDistance + ")");
}
}
}
//If the new route from root to neighbour is shorter than the old route or there was no old route
//set the current node as the first step towards the root from neighbour
else if (_cont && newDistance <= neighbour.GetDistanceFromRoot(ID)) {
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
if (_cont && _text) {
current.Say(neighbour.Name + ".cost (" + neighbour.GetDistanceFromRoot(ID) + ") > test cost (" +
newDistance + ")");
Pause();
current.Say("7. " + neighbour.Name + ".cost = test cost (" + newDistance + ")");
Pause();
}
}
} catch (KeyNotFoundException e) {
//If the AddLink being checked is no Keyer in the list of links the algorithm needs to stop
_cont = false;
if (_visualise)
VisualisedNode = null;
Logger.Debug("Trying to work with a neighbour (" + neighbour.Name + ") which is not actually connected to " +
current.Name + " (root = " + Name + ")");
}
if (_cont && newDistance < neighbour.GetDistanceFromRoot(ID))
neighbour.SetDistanceFromRoot(ID, newDistance, neighbour, link);
if (_cont) {
Pause(4f);
link.Colour = Color.White;
Pause(6f);
}
}
/// <summary>
/// The main loop which is the body of the algorithm.
/// Loops through every neighbour of the current node checking to see if they:
/// A. Have been visited before
/// B. Have been visited before but are now a shorter route
/// </summary>
/// <param name="current">The node currently being checked.</param>
/// <param name="prev">The previous node that was checked.</param>
/// <returns>The last node to be checked.</returns>
private void MainLoop(DijkstraNode current, DijkstraNode prev)
{
while (_cont && current != null && !hitTarget(current)) {
//If necessary display text and wait
if (_cont && _text && _visualise) {
current.Say("4. Iterating through neighbours excluding neighbours in Confirmed");
Pause();
}
//Get the current distance to the target
float dist = current.GetDistanceFromRoot(ID);
foreach (var n in current.Neighbours) {
IMLink link = current.Links[n.ID];
if (_visualise)
_links.AddFirst(link);
var neighbour = this.GetAlgNode<DijkstraNode>(n.ID);
if (_cont && !_confirmed.Contains(neighbour)) {
if (_visualise && _text)
VisualiseCheckNeighbourText(neighbour, current, dist, link);
else if (_visualise)
VisualiseCheckNeighbour(neighbour, current, dist, link);
checkNeighbour(neighbour, current, dist, link);
}
if (!_cont)
break;
}
//Store the old previous node
prev = current;
if (_cont && _text && _visualise) {
Say("Finished iterating through current's (" + current.Name +
"'s) neighbours, getting next current from tentative list");
Pause();
}
//Get the next node to be checked (the one which has the shortest path to it)
current = getNext(current);
}
FinishedReset(current, prev);
}
/// <summary>
/// Check a neighbour of the current node to see if it needs to be added to the tentative list
/// or the shortest route to it needs to be updated.
/// </summary>
/// <param name="neighbour">The neighbour to check.</param>
/// <param name="current">The current node.</param>
/// <param name="dist">The distance from the root to the current node.</param>
/// <param name="link">The link between current and neighbour.</param>
private void checkNeighbour(DijkstraNode neighbour, DijkstraNode current, float dist, IMLink link)
{
float newDistance = dist + link.Weight;
try {
//If the new route from root to neighbour is shorter than the old route or there was no old route
//set the current node as the first step towards the root from neighbour
if (_cont && !_tentative.Contains(neighbour)) {
_tentative.AddFirst(neighbour);
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
} else if (_cont && newDistance <= neighbour.GetDistanceFromRoot(ID))
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
} catch (KeyNotFoundException e) {
//If the AddLink being checked is no Keyer in the list of links the algorithm needs to stop
_cont = false;
if (_visualise)
VisualisedNode = null;
Logger.Debug("Trying to work with a neighbour (" + neighbour.Name + ") which is not actually connected to " +
current.Name + " (root = " + Name + ")");
}
//Incase another thread has modified the distance
if (_cont && newDistance < neighbour.GetDistanceFromRoot(ID))
neighbour.SetDistanceFromRoot(ID, newDistance, neighbour, link);
}
/// <summary>
/// Visualises the process of checking a neighbour node and prints out text explaining what is happening.
/// </summary>
/// <param name="neighbour">The neighbour to check.</param>
/// <param name="current">The current node.</param>
/// <param name="dist">The distance from the root to the current node.</param>
/// <param name="link">The link between current and neighbour.</param>
private void VisualiseCheckNeighbourText(DijkstraNode neighbour, DijkstraNode current, float dist, IMLink link)
{
if (!_visualise && !_text)
{
return;
}
float newDistance = dist + link.Weight;
if (_cont)
{
//if (_cont && _text)
// current.Say("Examining neighbour " + neighbour.Name);
Pause(4f);
link.Colour = Color.Blue;
if (_cont && _text)
{
Pause();
current.Say("5. Test cost to " + neighbour.Name + " = " + dist + " + " + link.Weight + " = " +
newDistance);
Pause();
}
Pause(4f);
}
try {
if (_cont && !_tentative.Contains(neighbour))
{
if (_cont && _text)
{
current.Say(neighbour.Name + " is not in tentative list");
}
_tentative.AddFirst(neighbour);
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
if (_cont)
{
Pause(4f);
neighbour.Selected = tentativeGlow;
if (_cont && _text)
{
current.Say("6a. Adding " + neighbour.Name + " to the tentative list");
Pause();
current.Say("6b. " + neighbour.Name + ".cost = test cost (" + newDistance + ")");
}
}
}
//If the new route from root to neighbour is shorter than the old route or there was no old route
//set the current node as the first step towards the root from neighbour
else if (_cont && newDistance <= neighbour.GetDistanceFromRoot(ID))
{
neighbour.SetDistanceFromRoot(ID, newDistance, current, link);
if (_cont && _text)
{
current.Say(neighbour.Name + ".cost (" + neighbour.GetDistanceFromRoot(ID) + ") > test cost (" +
newDistance + ")");
Pause();
current.Say("7. " + neighbour.Name + ".cost = test cost (" + newDistance + ")");
Pause();
}
}
} catch (KeyNotFoundException e) {
//If the AddLink being checked is no Keyer in the list of links the algorithm needs to stop
_cont = false;
if (_visualise)
{
VisualisedNode = null;
}
Logger.Debug("Trying to work with a neighbour (" + neighbour.Name + ") which is not actually connected to " +
current.Name + " (root = " + Name + ")");
}
if (_cont && newDistance < neighbour.GetDistanceFromRoot(ID))
{
neighbour.SetDistanceFromRoot(ID, newDistance, neighbour, link);
}
if (_cont)
{
Pause(4f);
link.Colour = Color.White;
Pause(6f);
}
}