/// <summary>
/// Reads a <see cref="GeoAPI.Geometries.Coordinate"/> from the current position.
/// It's akin to <see cref="WktShapeParser.State"/> but for
/// a NTS Coordinate. Only the first 2 numbers are parsed; any remaining are ignored.
/// </summary>
/// <param name="state"></param>
/// <returns></returns>
protected virtual Coordinate Coordinate(WktShapeParser.State state)
{
double x = m_ctx.NormX(state.NextDouble());
m_ctx.VerifyX(x);
double y = m_ctx.NormY(state.NextDouble());
m_ctx.VerifyY(y);
state.SkipNextDoubles();
return(new Coordinate(x, y));
}
protected override IShape ParseShapeByType(WktShapeParser.State state, string shapeType)
{
if (shapeType.Equals("POLYGON", StringComparison.OrdinalIgnoreCase))
{
return(ParsePolygonShape(state));
}
else if (shapeType.Equals("MULTIPOLYGON", StringComparison.OrdinalIgnoreCase))
{
return(ParseMulitPolygonShape(state));
}
return(base.ParseShapeByType(state, shapeType));
}
/// <summary>
/// Reads a NTS Coordinate sequence from the current position.
/// <code>
/// '(' coordinate (',' coordinate )* ')'
/// </code>
/// </summary>
protected virtual Coordinate[] CoordinateSequence(WktShapeParser.State state)
{
List <Coordinate> sequence = new List <Coordinate>();
state.NextExpect('(');
do
{
sequence.Add(Coordinate(state));
} while (state.NextIf(','));
state.NextExpect(')');
return(sequence.ToArray(/*new Coordinate[sequence.Count]*/));
}
/// <summary>
/// Reads a list of NTS Coordinate sequences from the current position.
/// <code>
/// '(' coordinateSequence (',' coordinateSequence )* ')'
/// </code>
/// </summary>
protected virtual IList <Coordinate[]> CoordinateSequenceList(WktShapeParser.State state)
{
IList <Coordinate[]> sequenceList = new List <Coordinate[]>();
state.NextExpect('(');
do
{
sequenceList.Add(CoordinateSequence(state));
} while (state.NextIf(','));
state.NextExpect(')');
return(sequenceList);
}
/// <summary>
/// Bypasses <see cref="NtsSpatialContext.MakeLineString(IList{Shapes.IPoint})"/> so that we can more
/// efficiently get the <see cref="LineString"/> without creating a <see cref="List{T}">List{Shapes.IPoint}</see>.
/// </summary>
protected override IShape ParseLineStringShape(WktShapeParser.State state)
{
if (!m_ctx.UseNtsLineString)
{
return(base.ParseLineStringShape(state));
}
if (state.NextIfEmptyAndSkipZM())
{
return(m_ctx.MakeLineString(new List <Shapes.IPoint>()));
}
GeometryFactory geometryFactory = m_ctx.GeometryFactory;
Coordinate[] coordinates = CoordinateSequence(state);
return(MakeShapeFromGeometry(geometryFactory.CreateLineString(coordinates)));
}
/// <summary>
/// Parses a MULTIPOLYGON shape from the raw string.
/// <code>
/// '(' polygon (',' polygon )* ')'
/// </code>
/// </summary>
protected virtual IShape ParseMulitPolygonShape(WktShapeParser.State state)
{
if (state.NextIfEmptyAndSkipZM())
{
return(m_ctx.MakeCollection(new List <IShape>()));
}
IList <IShape> polygons = new List <IShape>();
state.NextExpect('(');
do
{
polygons.Add(ParsePolygonShape(state));
} while (state.NextIf(','));
state.NextExpect(')');
return(m_ctx.MakeCollection(polygons));
}
/// <summary>
/// Reads a polygon, returning a NTS polygon.
/// </summary>
protected virtual IPolygon Polygon(WktShapeParser.State state)
{
GeometryFactory geometryFactory = m_ctx.GeometryFactory;
IList <Coordinate[]> coordinateSequenceList = CoordinateSequenceList(state);
ILinearRing shell = geometryFactory.CreateLinearRing(coordinateSequenceList[0]);
ILinearRing[] holes = null;
if (coordinateSequenceList.Count > 1)
{
holes = new ILinearRing[coordinateSequenceList.Count - 1];
for (int i = 1; i < coordinateSequenceList.Count; i++)
{
holes[i - 1] = geometryFactory.CreateLinearRing(coordinateSequenceList[i]);
}
}
return(geometryFactory.CreatePolygon(shell, holes));
}
/// <summary>
/// Parses a POLYGON shape from the raw string. It might return a <see cref="IRectangle"/>
/// if the polygon is one.
/// <code>
/// coordinateSequenceList
/// </code>
/// </summary>
/// <param name="state"></param>
/// <returns></returns>
protected virtual IShape ParsePolygonShape(WktShapeParser.State state)
{
IGeometry geometry;
if (state.NextIfEmptyAndSkipZM())
{
GeometryFactory geometryFactory = m_ctx.GeometryFactory;
geometry = geometryFactory.CreatePolygon(geometryFactory.CreateLinearRing(
new Coordinate[] { }), null);
}
else
{
geometry = Polygon(state);
if (geometry.IsRectangle)
{
//TODO although, might want to never convert if there's a semantic difference (e.g. geodetically)
return(MakeRectFromPoly(geometry));
}
}
return(MakeShapeFromGeometry(geometry));
}
