/// <summary>
/// Creates and returns a full copy of this <see cref="ILinearRing"/> object.
/// (including all coordinates contained by it).
/// </summary>
/// <returns>A copy of this instance</returns>
public override IGeometry Copy()
{
return(new LinearRing(CoordinateSequence.Copy(), Factory));
}
/// <summary>
/// Convenience method which provides a standard way of copying <see cref="CoordinateSequence"/>s.
/// </summary>
/// <param name="seq">The sequence to copy.</param>
/// <returns>A deep copy of the sequence.</returns>
protected virtual CoordinateSequence Copy(CoordinateSequence seq)
{
return(seq.Copy());
}
private static IEnumerable <uint> Encode(CoordinateSequence sequence, TileGeometryTransform tgt,
ref int currentX, ref int currentY,
bool ring = false, bool ccw = false)
{
// how many parameters for LineTo command
int count = sequence.Count;
// if we have a ring we need to check orientation
if (ring)
{
if (ccw != Algorithm.Orientation.IsCCW(sequence))
{
sequence = sequence.Copy();
CoordinateSequences.Reverse(sequence);
}
}
var encoded = new List <uint>();
// Start point
encoded.Add(GenerateCommandInteger(MapboxCommandType.MoveTo, 1));
var position = tgt.Transform(sequence, 0, ref currentX, ref currentY);
encoded.Add(GenerateParameterInteger(position.x));
encoded.Add(GenerateParameterInteger(position.y));
// Add LineTo command (stub)
int lineToCount = 0;
encoded.Add(GenerateCommandInteger(MapboxCommandType.LineTo, lineToCount));
for (int i = 1; i < count; i++)
{
position = tgt.Transform(sequence, i, ref currentX, ref currentY);
if (position.x != 0 || position.y != 0)
{
encoded.Add(GenerateParameterInteger(position.x));
encoded.Add(GenerateParameterInteger(position.y));
lineToCount++;
}
}
if (lineToCount > 0)
{
encoded[3] = GenerateCommandInteger(MapboxCommandType.LineTo, lineToCount);
}
// Validate encoded data
if (ring)
{
// A ring has 1 MoveTo and 1 LineTo command.
// A ring is only valid if we have at least 3 points, otherwise collapse
if (encoded.Count - 2 >= 6)
{
encoded.Add(GenerateCommandInteger(MapboxCommandType.ClosePath, 1));
}
else
{
encoded.Clear();
}
}
else
{
// A line has 1 MoveTo and 1 LineTo command.
// A line is valid if it has at least 2 points
if (encoded.Count - 2 < 4)
{
encoded.Clear();
}
}
return(encoded);
}
