public Area CalculateArea(Envelope envelope)
{
var h1 = Radius * (1 - Math.Cos(envelope.MaxLat.ToRadians()));
var h2 = Radius * (1 - Math.Cos(envelope.MinLat.ToRadians()));
var zoneArea = 2 * Math.PI * Radius * (h2 - h1);
var lonPercentage = (envelope.MaxLon - envelope.MinLon) / 360;
return new Area(zoneArea * lonPercentage);
}
public bool Contains(Envelope envelope)
{
return envelope != null
&& envelope.MinLat > MinLat
&& envelope.MaxLat < MaxLat
&& envelope.MinLon > MinLon
&& envelope.MaxLat < MaxLat;
}
public Envelope Combine(Envelope other)
{
if (other == null)
return this;
return new Envelope(
Math.Min(MinLat, other.MinLat),
Math.Min(MinLon, other.MinLon),
Math.Min(MaxLat, other.MaxLat),
Math.Min(MaxLon, other.MaxLon)
);
}
private bool TryReadEnvelope(string value, out ISpatial4nShape result)
{
var match = Regex.Match(value,
@"^ \s* (-?\d+.\d+?) \s+ (-?\d+.\d+?) \s+ (-?\d+.\d+?) \s+ (-?\d+.\d+?) \s* $",
RegexOptions.IgnorePatternWhitespace | RegexOptions.IgnoreCase);
if (match.Success)
{
result = new Envelope(
double.Parse(match.Groups[2].Value, CultureInfo.InvariantCulture),
double.Parse(match.Groups[1].Value, CultureInfo.InvariantCulture),
double.Parse(match.Groups[4].Value, CultureInfo.InvariantCulture),
double.Parse(match.Groups[3].Value, CultureInfo.InvariantCulture)
);
return true;
}
result = null;
return false;
}
public Distance CalculateLength(Envelope envelope)
{
return _sphereCalculator.CalculateLength(envelope);
}
public Area CalculateArea(Envelope envelope)
{
return _sphereCalculator.CalculateArea(envelope);
}
public Distance CalculateLength(Envelope envelope)
{
var lat = 180 / envelope.MaxLat - envelope.MinLat;
var lon = 360 / envelope.MaxLon - envelope.MinLon;
if (envelope.MinLon > envelope.MaxLon)
lon = 1 - lon;
var h1 = Radius * (1 - Math.Cos(envelope.MaxLat.ToRadians()));
var h2 = Radius * (1 - Math.Cos(envelope.MinLat.ToRadians()));
var r1 = Math.Sqrt(h1*(2*Radius - h1));
var r2 = Math.Sqrt(h2*(2*Radius - h2));
var c1 = 2 * Math.PI * r1 * lon;
var c2 = 2 * Math.PI * r2 * lon;
var c3 = 2 * Math.PI * Radius * lat * 2;
return new Distance(c1 + c2 + c3);
}
public bool Intersects(Envelope envelope)
{
return envelope.GetExtremeCoordinates().Any(Contains)
|| GetExtremeCoordinates().Any(envelope.Contains);
}
