internal static IList <double[]> GetLimits([NotNull] SegmentProxy segmentProxy,
[NotNull] IPolygon buffer)
{
// TODO this method would be extremely expensive when called on WksSegmentProxy instances
var result = new List <double[]>();
// Remark: segmentLine is altered by ITopologicalOperator.Intersect in such a way
// that equal segments may not be considered as equal anymore
IPolyline segmentLine = segmentProxy.GetPolyline(true);
//IPolyline segmentLine = segmentProxy.GetPolyline();
var intersects = (IGeometryCollection)
((ITopologicalOperator)buffer).Intersect(
segmentLine,
esriGeometryDimension.esriGeometry1Dimension);
int intersectCount = intersects.GeometryCount;
for (var i = 0; i < intersectCount; i++)
{
var part = (IPath)intersects.Geometry[i];
double t0 = 0;
double t1 = 0;
double offset = 0;
var rightSide = false;
// TODO if called frequently, create abstract GetSegmentDistance(IPoint) on SegmentProxy,
// with custom implementation on WksSegmentProxy.
// Currently this seems to be called for AoSegmentProxys only, but this is not obvious.
// TODO use a template point and part.QueryFromPoint() / part.QueryToPoint()?
segmentLine.QueryPointAndDistance(esriSegmentExtension.esriExtendTangents,
part.FromPoint, true, HelpPoint,
ref t0, ref offset, ref rightSide);
segmentLine.QueryPointAndDistance(esriSegmentExtension.esriExtendTangents,
part.ToPoint, true, HelpPoint,
ref t1, ref offset, ref rightSide);
double tMin = Math.Min(t0, t1);
double tMax = Math.Max(t0, t1);
result.Add(new[] { tMin, tMax });
}
// Handle spatial tolerance problems for segments near tolerance size!
if (intersectCount == 0 && !((IRelationalOperator)buffer).Disjoint(segmentLine))
{
((ITopologicalOperator)segmentLine).Simplify();
if (segmentLine.IsEmpty)
{
result.Add(new[] { 0.0, 1.0 });
}
}
return(result);
}
public static double GetClosestPointFraction([NotNull] SegmentProxy segmentProxy,
[NotNull] Pnt nearPoint,
out double?offset,
out bool?onRightSide,
bool as3D)
{
if (segmentProxy.IsLinear)
{
Pnt p0s = segmentProxy.GetStart(as3D);
Pnt p0e = segmentProxy.GetEnd(as3D);
Pnt l0 = p0e - p0s;
offset = null;
onRightSide = null;
return(GetAlongFraction(nearPoint - p0s, l0));
}
const bool forceCreation = true;
IPolyline segmentLine = segmentProxy.GetPolyline(forceCreation);
IPoint near = new PointClass();
near.PutCoords(nearPoint.X, nearPoint.Y);
IPoint onPoint = new PointClass();
double fraction = 0;
double offsetValue = 0;
var rightSide = false;
const bool asRatio = true;
segmentLine.QueryPointAndDistance(esriSegmentExtension.esriNoExtension, near,
asRatio, onPoint, ref fraction,
ref offsetValue, ref rightSide);
offset = offsetValue;
onRightSide = rightSide;
return(fraction);
}
private static bool GetCoincident([NotNull] SegmentProxy segment,
[NotNull] SegmentProxy hull,
bool is3D,
out NearSegment hullStartNear,
out NearSegment hullEndNear)
{
hullStartNear = NearSegment.NotNear; // TODO
hullEndNear = NearSegment.NotNear; // TODO
IPolyline segLine = segment.GetPolyline(false);
IPolyline hullLine = hull.GetPolyline(false);
if (!((IRelationalOperator)segLine).Equals(hullLine))
{
return(false);
}
var coincident = true;
Pnt segmentStart = segment.GetStart(is3D);
Pnt segmentEnd = segment.GetEnd(is3D);
Pnt hullStart = hull.GetStart(is3D);
Pnt hullEnd = hull.GetEnd(is3D);
double distFromSegFromHull;
{
double dx = segmentStart.X - hullStart.X;
double dy = segmentStart.Y - hullStart.Y;
distFromSegFromHull = dx * dx + dy * dy;
}
double distFromSegToHull;
{
double dx = segmentStart.X - hullEnd.X;
double dy = segmentStart.Y - hullEnd.Y;
distFromSegToHull = dx * dx + dy * dy;
}
bool isInverse = (distFromSegFromHull > distFromSegToHull);
Pnt hullMatchSegFrom;
Pnt hullMatchSegTo;
if (!isInverse)
{
hullMatchSegFrom = hullStart;
hullMatchSegTo = hullEnd;
}
else
{
hullMatchSegFrom = hullEnd;
hullMatchSegTo = hullStart;
}
if (is3D)
{
double zPrecision = 0;
ISpatialReference spatialReference = segment.SpatialReference;
if (spatialReference != null && spatialReference.HasZPrecision())
{
double falseZ;
double zUnits;
spatialReference.GetZFalseOriginAndUnits(out falseZ, out zUnits);
zPrecision = 1 / zUnits;
}
if (Math.Abs(hullMatchSegFrom[2] - segmentStart[2]) > zPrecision ||
Math.Abs(hullMatchSegTo[2] - segmentStart[2]) > zPrecision)
{
coincident = false;
}
}
if (coincident)
{
if (!isInverse)
{
hullStartNear = NearSegment.NearStart;
hullEndNear = NearSegment.NearEnd;
}
else
{
hullStartNear = NearSegment.NearEnd;
hullEndNear = NearSegment.NearStart;
}
}
return(coincident);
}
