// This is where the real work is done.
public void AddLine(double x, double y, double?z, double?m)
{
// If we've already found a point, then we're done. We just need to keep ignoring these
// pesky calls.
if (_foundPoint != null)
{
return;
}
// Make a point for our current position.
var thisPoint = CheckShapePointAndGet(m, Ext.GetPoint(x, y, z, m, _srid));
// is the found point between this point and the last, or past this point?
if (m != null && _measure.IsWithinRange(_lastPoint.M.Value, m.Value))
{
// now we need to do the hard work and find the point in between these two
_foundPoint = Functions.LRS.Geometry.InterpolateBetweenGeom(_lastPoint, thisPoint, _measure);
if (_lastPoint.IsWithinTolerance(_foundPoint, _tolerance))
{
_foundPoint = _lastPoint;
IsShapePoint = true;
}
else if (thisPoint.IsWithinTolerance(_foundPoint, _tolerance))
{
_foundPoint = thisPoint;
IsShapePoint = true;
}
}
else
{
// it's past this point---just step along the line
_lastPoint = thisPoint;
}
}
/// <summary>
/// Utility Method for removing the consecutive duplicate vertices
/// </summary>
/// <param name="geometry"></param>
/// <param name="tolerance"></param>
/// <returns></returns>
public static SqlGeometry RemoveDuplicateVertices(SqlGeometry geometry, double tolerance = Constants.Tolerance)
{
if (!geometry.STIsValid())
{
Ext.ThrowIfInvalidGeometry();
}
return(geometry.Reduce(tolerance));
}
// Start the figure. Note that since we only operate on LineStrings, this should only be executed
// once.
public void BeginFigure(double x, double y, double?z, double?m)
{
if (_foundPoint != null)
{
return;
}
// Memorize the point.
_lastPoint = CheckShapePointAndGet(m, Ext.GetPoint(x, y, z, m, _srid));
}
// This is where the real work is done.
public void AddLine(double x, double y, double?z, double?m)
{
// To unify code for ascending and descending measures - clipPointMeasure
double?clipPointMeasure = GetClipPointMeasure(m);
double newX, newY;
// If current measure is between start measure and end measure,
// we should add segment to the result linestring
if (m.IsWithinRange(_clipStartMeasure, _clipEndMeasure))
{
// if the geometry is started, just add the point to line
if (_started)
{
_target.AddLine(x, y, z, m);
}
// Else we need to begin the geom figure first
else
{
var isShapePoint = false;
// if clip point is shape point measure then add the point without computation
if (m.EqualsTo(clipPointMeasure))
{
_target.BeginFigure(x, y, null, m);
isShapePoint = true;
}
else
{
ComputePointCoordinates(clipPointMeasure, m, x, y, out newX, out newY);
// if computed point is within tolerance of last point then begin figure with last point
if (Ext.IsWithinTolerance(_previousX, _previousY, newX, newY, _tolerance))
{
_target.BeginFigure(_previousX, _previousY, null, _retainClipMeasure ? _clipStartMeasure : _previousM);
}
// check with current point against new computed point
else if (Ext.IsWithinTolerance(x, y, newX, newY, _tolerance))
{
_target.BeginFigure(x, y, null, m);
isShapePoint = true;
}
// else begin figure with clipped point
else
{
_target.BeginFigure(newX, newY, null, clipPointMeasure);
}
}
_started = true;
if (_clipStartMeasure.EqualsTo(_clipEndMeasure) || isShapePoint)
{
UpdateLastPoint(x, y, m);
return;
}
_target.AddLine(x, y, z, m);
}
}
// We may still need to add last segment,
// if current point is the first one after we passed range of interest
else
{
if (!_started)
{
var isShapePoint = false;
if (clipPointMeasure.IsWithinRange(m, _previousM))
{
ComputePointCoordinates(clipPointMeasure, m, x, y, out newX, out newY);
// if computed point is within tolerance of last point then begin figure with last point
if (Ext.IsWithinTolerance(_previousX, _previousY, newX, newY, _tolerance))
{
_target.BeginFigure(_previousX, _previousY, null, _retainClipMeasure ? clipPointMeasure : _previousM);
}
// check with current point against new computed point
else if (Ext.IsWithinTolerance(x, y, newX, newY, _tolerance))
{
_target.BeginFigure(x, y, null, _retainClipMeasure ? clipPointMeasure : m);
isShapePoint = true;
}
// else begin figure with clipped point
else
{
_target.BeginFigure(newX, newY, null, clipPointMeasure);
}
_started = true;
if (_clipStartMeasure.EqualsTo(_clipEndMeasure) || isShapePoint)
{
UpdateLastPoint(x, y, m);
return;
}
}
}
if (_started && !_finished)
{
// re calculate clip point measure as it can be changed from above condition.
clipPointMeasure = GetClipPointMeasure(m);
if (clipPointMeasure.IsWithinRange(m, _previousM))
{
ComputePointCoordinates(clipPointMeasure, m, x, y, out newX, out newY);
var isWithinLastPoint = Ext.IsWithinTolerance(_previousX, _previousY, newX, newY, _tolerance);
var isWithinCurrentPoint = Ext.IsWithinTolerance(x, y, newX, newY, _tolerance);
// if computed point is within tolerance of last point then skip
if (!isWithinLastPoint)
{
// if within current point then add current point
if (isWithinCurrentPoint)
{
_target.AddLine(x, y, null, _retainClipMeasure ? clipPointMeasure : m);
}
// else add computed point
else
{
_target.AddLine(newX, newY, null, clipPointMeasure);
}
}
_finished = true;
}
}
}
// re-assign the current co-ordinates to match for next iteration.
UpdateLastPoint(x, y, m);
}
public static SqlGeometry ExtractGeometry(SqlGeometry sqlGeometry, int elementIndex, int ringIndex = 0)
{
if (sqlGeometry.IsNullOrEmpty())
{
return(sqlGeometry);
}
// GEOMETRYCOLLECTION
if (sqlGeometry.IsGeometryCollection())
{
if (elementIndex == 0 || elementIndex > sqlGeometry.STNumGeometries())
{
Ext.ThrowInvalidElementIndex();
}
// reset geometry and element index and pass through
sqlGeometry = sqlGeometry.STGeometryN(elementIndex);
elementIndex = 1;
// if the resultant is MULTILINE; reset the ring index and assign it to element index
if (sqlGeometry.IsMultiLineString())
{
elementIndex = ringIndex;
ringIndex = 0;
}
}
// Handle for Curve Polygon with Compound Curve
if (sqlGeometry.IsCurvePolygon())
{
if (elementIndex != 1)
{
Ext.ThrowInvalidElementIndex();
}
if (ringIndex == 0)
{
return(sqlGeometry);
}
// re-assign sub component; if it is a COMPOUND CURVE
var subComponent = ringIndex == 1 ? sqlGeometry.STExteriorRing() : sqlGeometry.STInteriorRingN(ringIndex - 1); // subtracting exterior ring count
if (subComponent.IsCompoundCurve())
{
sqlGeometry = subComponent;
elementIndex = 1;
ringIndex = 1;
}
}
var isSimpleType = sqlGeometry.IsPoint() || sqlGeometry.IsLineString() || sqlGeometry.IsCircularString();
// if simple type then return input geometry when index is 1 or 0
if (isSimpleType)
{
if (elementIndex != 1)
{
Ext.ThrowInvalidElementIndex();
}
if (ringIndex > 1)
{
Ext.ThrowInvalidSubElementIndex();
}
if (isSimpleType && ringIndex <= 1)
{
return(sqlGeometry);
}
}
// MULTIPOINT
if (sqlGeometry.IsMultiPoint())
{
if (elementIndex != 1)
{
Ext.ThrowInvalidElementIndex();
}
if (ringIndex == 0)
{
return(sqlGeometry);
}
var obtainedGeom = sqlGeometry.STGeometryN(ringIndex);
if (obtainedGeom == null || obtainedGeom.IsNull)
{
Ext.ThrowInvalidSubElementIndex();
}
return(obtainedGeom);
}
// MULTILINESTRING
if (sqlGeometry.IsMultiLineString())
{
if (elementIndex > sqlGeometry.STNumGeometries())
{
Ext.ThrowInvalidElementIndex();
}
if (ringIndex > 1)
{
Ext.ThrowInvalidSubElementIndex();
}
return(sqlGeometry.STGeometryN(elementIndex));
}
// COMPOUND CURVE
if (sqlGeometry.IsCompoundCurve())
{
if (elementIndex != 1)
{
Ext.ThrowInvalidElementIndex();
}
if (ringIndex > 1)
{
Ext.ThrowInvalidSubElementIndex();
}
return(sqlGeometry);
}
// POLYGON and CURVEPOLYGON
if (sqlGeometry.IsPolygon() || sqlGeometry.IsCurvePolygon())
{
if (elementIndex != 1)
{
Ext.ThrowInvalidElementIndex();
}
// if sub element index is zero then return the input geometry
if (ringIndex == 0)
{
return(sqlGeometry);
}
if (ringIndex > sqlGeometry.STNumInteriorRing() + 1)
{
Ext.ThrowInvalidSubElementIndex();
}
return(GetPolygon(sqlGeometry, ringIndex));
}
// MULTIPOLYGON
if (sqlGeometry.IsMultiPolygon())
{
if (elementIndex == 0 || elementIndex > sqlGeometry.STNumGeometries())
{
Ext.ThrowInvalidElementIndex();
}
sqlGeometry = sqlGeometry.STGeometryN(elementIndex);
// if sub element index is zero then return the input geometry
if (ringIndex == 0)
{
return(sqlGeometry);
}
if (ringIndex > sqlGeometry.STNumInteriorRing() + 1)
{
Ext.ThrowInvalidSubElementIndex();
}
return(GetPolygon(sqlGeometry, ringIndex));
}
return(sqlGeometry);
}
