private double CalculateProb(NodeXY node1, NodeXY node2, out double gradient, double dist)
{
gradient = node1.Height - node2.Height;
double p;
double g = (gradient / _initNodeHeight) * 100.0;
double pp = Math.Sqrt(Math.Pow(_nodes[Target].Coords.X - node2.Coords.X, 2) + Math.Pow(_nodes[Target].Coords.Y - node2.Coords.Y, 2));;
if (gradient > 0)
{
//p = gradient / (dist + 1);
//p = gradient;
//p = Math.Pow(pBase, gradient) / (dist + 1) + pSeed;
p = Math.Pow(_pBase, g);
}
else if (gradient == 0)
{
p = Math.Pow(_pBase, g);
//p = rng.NextDouble() / 10;
//p = Math.Pow(pBase, gradient) / (dist + 1) + pSeed;
//p = delta / Distance(w, currentNode);
//p = delta / (dist + 1);
//p = _delta;
}
else
{
p = Math.Pow(_pBase, g);
//p = _omega;
//p = omega / (gradient * -1) / (dist + 1);
//p = _omega / (gradient * -1);
//p = Math.Pow(pBase, gradient) / (dist + 1) + pSeed;
}
return(p / Math.Pow(5, pp));
}
private double CalculateErosion(NodeXY node1, NodeXY node2)
{
double gradient = node1.Height - node2.Height;
double g = (gradient / _initNodeHeight) * 100.0;
double erosion;
if (gradient > 0.0)
{
//erosion = (_paramErosion / ((_nodes.Count - 1) * _populationSize)) * gradient;
erosion = Math.Pow(_pEBase, gradient);
}
else if (gradient == 0.0)
{
erosion = _eFlat;
//erosion = Math.Pow(pEBase_, gradient);
}
else
{
erosion = _eUp;
//erosion = Math.Pow(pEBase_, gradient);
}
return(erosion);
}
public Drop2()
{
sediment = 0;
path = new List <int>();
pathLength = 0;
bestPath = new List <int>();
bestPathLength = 999999;
evaporated = false;
canClimb = false;
currentNode = null;
}
private void ErodePath(Drop2 drop)
{
for (int i = 0; i < drop.path.Count - 1; i++)
{
NodeXY a = _nodes[drop.path[i]];
NodeXY b = _nodes[drop.path[i + 1]];
double erosion = CalculateErosion(a, b) / drop.pathLength;
a.Height -= erosion;
_erosionProduced += erosion;
}
}
private void moveDrop(Drop2 drop, double climbingProbability)
{
drop.evaporated = false;
drop.canClimb = false;
drop.path = new List <int>();
drop.pathLength = 0.0;
drop.sediment = 0.0;
drop.currentNode = _nodes[_source];
drop.path.Add(_source);
double rC = _rng.NextDouble();
if (rC <= climbingProbability)
{
drop.canClimb = true;
}
while (drop.currentNode.Index != _target && !drop.evaporated)
{
int nextNodeIdx = PickNextNode(drop.currentNode);
NodeXY nextNode = drop.currentNode.Neighbours[nextNodeIdx];
if (drop.path.Count >= _nodes.Count)
{
drop.evaporated = true;
break;
}
drop.pathLength += drop.currentNode.NeighbourDistance[nextNodeIdx];
drop.currentNode = nextNode;
drop.path.Add(nextNode.Index);
}
if (drop.evaporated)
{
}
else
{
ErodePath(drop);
if (drop.pathLength < drop.bestPathLength)
{
drop.bestPathLength = drop.pathLength;
drop.bestPath = new List <int>(drop.path);
}
if (drop.pathLength < _bestPathLength)
{
_bestPathLength = drop.pathLength;
_bestPath = new List <int>(drop.path);
}
}
}
private int PickNextNode(NodeXY currentNode)
{
List <NodeXY> neighbours = currentNode.Neighbours;
double[] probs = new double[neighbours.Count];
for (int i = 0; i < neighbours.Count; i++)
{
if (neighbours[i].Status == 1)
{
double gradient;
probs[i] = CalculateProb(currentNode, neighbours[i], out gradient, currentNode.NeighbourDistance[i]);
}
}
return(_rouletteWheel.ChooseAction(probs));
}