/// <summary>
/// Calculate the distance between x,y and the datapoint.
/// </summary>
/// <param name="datapoint">The datapoint constituting the one end of the line.</param>
/// <param name="x">The x-value of the other end of the line.</param>
/// <param name="y">The y-value of the other end of the line.</param>
/// <returns>The euclidean distance between the two points.</returns>
private double GetDistance(HeatDatapoint datapoint, double x, double y)
{
if (_config.ManhattanDistance)
{
return(Math.Abs(datapoint.X - x) + Math.Abs(datapoint.Y - y));
}
else
{
return(Math.Sqrt(Math.Pow(datapoint.X - x, 2) + Math.Pow(datapoint.Y - y, 2)));
}
}
/// <summary>
/// Gets the value of the datapoint according to the given tile center.
/// </summary>
/// <param name="x">The x-value of the center of the heat tile.</param>
/// <param name="y">The y-value of the center of the heat tile.</param>
/// <param name="datapoint">The datapoint to weight.</param>
/// <returns>Either the actual value of the datapoint or the same weighted by the distance to the tile center.</returns>
private double GetWeightedValue(double x, double y, HeatDatapoint datapoint)
{
if (_config.WeightByDistance)
{
// Weight datapoint value by the distance to the tiles center
return((1.0 - GetDistance(datapoint, x, y) / Radius) * datapoint.GetValue(_config.DataIndex));
}
else
{
return(datapoint.GetValue(_config.DataIndex));
}
}