/// <summary>
/// Get a function to calculate properties for a set given edge attributes.
/// </summary>
/// <returns></returns>
public sealed override EdgeFactor Factor(IAttributeCollection attributes)
{
lock (_script)
{
// build lua table.
_attributesTable.Clear();
if (attributes == null || attributes.Count == 0)
{
return(EdgeFactor.NoFactor);
}
foreach (var attribute in attributes)
{
_attributesTable.Set(attribute.Key, DynValue.NewString(attribute.Value));
}
// call factor_and_speed function.
_resultsTable.Clear();
_script.Call(_script.Globals["factor"], _attributesTable, _resultsTable);
// get the results.
if (!_resultsTable.TryGetDouble("forward", out var forwardFactor))
{
forwardFactor = 0;
}
if (!_resultsTable.TryGetDouble("backward", out var backwardFactor))
{
backwardFactor = 0;
}
if (!_resultsTable.TryGetBool("canstop", out var canstop))
{
canstop = backwardFactor != 0 || forwardFactor != 0;
}
// the speeds are supposed to be in m/s.
if (!_resultsTable.TryGetDouble("forward_speed", out var speedForward))
{ // when forward_speed isn't explicitly filled, the assumption is that factors are in 1/(m/s)
speedForward = 0;
if (forwardFactor > 0)
{ // convert to m/s.
speedForward = 1.0 / forwardFactor;
}
}
else
{ // when forward_speed is filled, it's assumed to be in km/h, it needs to be convert to m/s.
speedForward /= 3.6;
}
if (!_resultsTable.TryGetDouble("backward_speed", out var speedBackward))
{ // when backward_speed isn't explicitly filled, the assumption is that factors are in 1/(m/s)
speedBackward = 0;
if (backwardFactor > 0)
{ // convert to m/s.
speedBackward = 1.0 / backwardFactor;
}
}
else
{ // when forward_speed is filled, it's assumed to be in km/h, it needs to be convert to m/s.
speedBackward /= 3.6;
}
return(new EdgeFactor((uint)(forwardFactor * 100), (uint)(backwardFactor * 100),
(ushort)(speedForward * 100), (ushort)(speedBackward * 100), canstop));
}
}
