/// <summary>
/// Calculates the intersection of a polygon shape without relying on the NTS geometry
/// </summary>
/// <param name="polygonShape"></param>
/// <param name="otherShape"></param>
/// <returns></returns>
public static bool Intersects(ShapeRange polygonShape, ShapeRange otherShape)
{
if (polygonShape.FeatureType != FeatureTypes.Polygon)
{
throw new ArgumentException("The First parameter should be a point shape, but it was featuretype:" + polygonShape.FeatureType);
}
// Extents will have already been tested by this point.
// Regardless of what the other shapetype is, a coordinate inside this polygon indicates a hit.
if (ContainsVertex(polygonShape, otherShape)) return true;
// There is no other way for this polygon to intersect the other points
if(otherShape.FeatureType == FeatureTypes.Point || otherShape.FeatureType ==FeatureTypes.MultiPoint)
return false;
// For lines and polygons, if any segment intersects any segment of this polygon shape, return true.
// This is essentially looking for the rare case of crossing in and crossing out again with
// no actual points inside this polygonShape.
if (LineShape.SegmentsIntersect(polygonShape, otherShape)) return true;
// There is no other way for this polygon to intersect the other lines
if (otherShape.FeatureType == FeatureTypes.Line) return false;
// If the other polygon completely contains this polygon every other test has returned false,
// but this will test for that case with only a single point.
Vertex v = polygonShape.First();
ShapeRange onlyFirstPoint = new ShapeRange(polygonShape.First());
return ContainsVertex(otherShape, onlyFirstPoint);
}
/// <summary>
/// Creates a shape based on the specified feature. This shape will be standing alone,
/// all by itself. The fieldnames and field types will be null.
/// </summary>
/// <param name="feature"></param>
public Shape(IFeature feature)
{
_shapeRange = new ShapeRange(feature.FeatureType);
_attributes = feature.DataRow.ItemArray;
IList<Coordinate> coords = feature.Coordinates;
_vertices = new double[feature.NumPoints*2];
_z = new double[feature.NumPoints];
_m = new double[feature.NumPoints];
for (int i = 0; i < coords.Count; i++)
{
Coordinate c = coords[i];
_vertices[i*2] = c.X;
_vertices[i*2 + 1] = c.Y;
_z[i] = c.Z;
_m[i] = c.M;
}
int offset = 0;
for(int ig = 0; ig < feature.NumGeometries; ig++)
{
IBasicGeometry g = feature.GetBasicGeometryN(ig);
PartRange prt = new PartRange(_vertices, 0, offset, feature.FeatureType);
_shapeRange.Parts.Add(prt);
offset += g.NumPoints;
}
}
/// <summary>
/// Calculates the intersection of a polygon shape without relying on the NTS geometry
/// </summary>
/// <param name="lineShape"></param>
/// <param name="otherShape"></param>
/// <returns></returns>
public static bool Intersects(ShapeRange lineShape, ShapeRange otherShape)
{
if (lineShape.FeatureType != FeatureTypes.Line)
{
throw new ArgumentException("The First parameter should be a point shape, but it was featuretype:" + lineShape.FeatureType);
}
// Implmented in PolygonShape
if(otherShape.FeatureType == FeatureTypes.Polygon)
{
return otherShape.Intersects(lineShape);
}
// Test for point on a line
if(otherShape.FeatureType == FeatureTypes.Point || otherShape.FeatureType == FeatureTypes.MultiPoint)
{
return IntersectsVertex(lineShape, otherShape);
}
// There is no other way for this polygon to intersect the other points
if (otherShape.FeatureType == FeatureTypes.Point || otherShape.FeatureType == FeatureTypes.MultiPoint)
return false;
// For lines and polygons, if any segment intersects any segment of this polygon shape, return true.
// This is essentially looking for the rare case of crossing in and crossing out again with
// no actual points inside this polygonShape.
return SegmentsIntersect(lineShape, otherShape);
}
/// <summary>
/// Calculates the intersection of a polygon shape without relying on the NTS geometry
/// </summary>
/// <param name="pointShape"></param>
/// <param name="otherShape"></param>
/// <returns></returns>
public static bool Intersects(ShapeRange pointShape, ShapeRange otherShape)
{
if(pointShape.FeatureType != FeatureTypes.Point && pointShape.FeatureType != FeatureTypes.MultiPoint)
{
throw new ArgumentException("The First parameter should be a point shape, but it was featuretype:" + pointShape.FeatureType);
}
// Implmented in PolygonShape or line shape. Point shape is the simplest and just looks for overlapping coordinates.
if (otherShape.FeatureType == FeatureTypes.Polygon || otherShape.FeatureType == FeatureTypes.Line)
{
return otherShape.Intersects(pointShape);
}
// For two point-type shapes, test if any vertex from one overlaps with any vertex of the other within Epsilon tollerance
return VerticesIntersect(pointShape, otherShape);
}
/// <summary>
/// Returns true if any vertices overlap
/// </summary>
/// <returns></returns>
public static bool VerticesIntersect(ShapeRange pointShape, ShapeRange otherPointShape)
{
foreach (PartRange part in pointShape.Parts)
{
foreach (PartRange oPart in otherPointShape.Parts)
{
foreach(Vertex v1 in part)
{
foreach (Vertex v2 in oPart)
{
if(v1 == v2) return true;
}
}
}
}
return false;
}
/// <summary>
/// Creates a new shape type where the shaperange exists and has a type specified
/// </summary>
/// <param name="type"></param>
public Shape(FeatureTypes type)
{
_shapeRange = new ShapeRange(type);
}
private static void ReadMultiPolygon(Stream data, FeatureSetPack results)
{
int numPolygons = ReadInt32(data);
ShapeRange lShp = new ShapeRange(FeatureTypes.Polygon);
List<double[]> rings = new List<double[]>();
int partOffset = 0;
for (int iPoly = 0; iPoly < numPolygons; iPoly++ )
{
data.Seek(5, SeekOrigin.Current); // endian and geometry type
int numRings = ReadInt32(data);
for (int iRing = 0; iRing < numRings; iRing++)
{
int numPoints = ReadInt32(data); // ring structures are like a linestring without the final point.
double[] coords = ReadDouble(data, 2 * numPoints);
if (iRing == 0)
{
// By shapefile standard, the shell should be clockwise
if (IsCounterClockwise(coords)) ReverseCoords(coords);
}
else
{
// By shapefile standard, the holes should be counter clockwise.
if (!IsCounterClockwise(coords)) ReverseCoords(coords);
}
PartRange lPrt = new PartRange(FeatureTypes.Polygon);
lPrt.PartOffset = partOffset;
lPrt.NumVertices = numPoints;
lShp.Parts.Add(lPrt);
partOffset += coords.Length / 2;
rings.Add(coords);
}
}
double[] allVertices = new double[partOffset * 2];
int offset = 0;
foreach (double[] ring in rings)
{
Array.Copy(ring, 0, allVertices, offset, ring.Length);
offset += ring.Length;
}
results.Add(allVertices, lShp);
}
/// <summary>
/// For each coordinate in the other part, if it falls in the extent of this polygon, a
/// ray crossing test is used for point in polygon testing. If it is not in the extent,
/// it is skipped.
/// </summary>
/// <param name="polygonShape">The part of the polygon to analyze polygon</param>
/// <param name="otherPart">The other part</param>
/// polygonshape and the shape extent is the same as the part extent.</param>
/// <returns>Boolean, true if any coordinate falls inside the polygon</returns>
private static bool ContainsVertex(ShapeRange polygonShape, PartRange otherPart)
{
// Create an extent for faster checking in most cases
Extent ext = polygonShape.Extent;
foreach (Vertex point in otherPart)
{
// This extent check shortcut should help speed things up for large polygon parts
if (!ext.Intersects(point)) continue;
// Imagine a ray on the horizontal starting from point.X -> infinity. (In practice this can be ext.XMax)
// Count the intersections of segments with that line. If the resulting count is odd, the point is inside.
double x1 = point.X;
double y1 = point.Y;
double x2 = ext.XMax;
Segment ray = new Segment(point.X, point.Y, ext.XMax, point.Y);
int[] numCrosses = new int[polygonShape.NumParts]; // A cross is a complete cross. Coincident doesn't count because it is either 0 or 2 crosses.
int totalCrosses = 0;
int iPart = 0;
foreach (PartRange ring in polygonShape.Parts)
{
foreach (Segment segment in ring.Segments)
{
if(segment.IntersectionCount(ray) != 1) continue;
numCrosses[iPart]++;
totalCrosses++;
}
iPart++;
}
// If we didn't actually have any polygons we cant intersect with anything
if (polygonShape.NumParts < 1) return false;
// For shapes with only one part, we don't need to test part-containment.
if(polygonShape.NumParts == 1 && totalCrosses % 2 == 1) return true;
// Regardless of number of parts or holiness, 1 crossing can only be inside.
if(totalCrosses == 1) return true;
totalCrosses = 0;
for (iPart = 0; iPart < numCrosses.Length; iPart++)
{
int count = numCrosses[iPart];
// If this part does not contain the point, don't bother trying to figure out if the part is a hole or not.
if (count % 2 == 0) continue;
// If this particular part is a hole, subtract the total crosses by 1, otherwise add one.
// This takes time, so we want to do this as few times as possible.
if(polygonShape.Parts[iPart].IsHole())
{
totalCrosses--;
}
else
{
totalCrosses++;
}
}
return totalCrosses > 0;
}
return false;
}
/// <summary>
/// returns only the features that have envelopes that
/// intersect with the specified envelope. If in indexMode, this uses the ShapeIndices to create
/// features on demand, rather than loading all the features. It is much faster to use selectIndices
/// when in index mode.
/// </summary>
/// <param name="region">The specified region to test for intersect with</param>
/// <param name="affectedRegion">This returns the geographic extents that contains the modified contents.</param>
/// <returns>A List of the IFeature elements that are contained in this region</returns>
public virtual List<IFeature> Select(IEnvelope region, out IEnvelope affectedRegion)
{
List<IFeature> result = new List<IFeature>();
if(IndexMode)
{
ShapeRange aoi = new ShapeRange(new Extent(region));
IEnvelope env = region.Copy();
Extent affected = new Extent();
List<ShapeRange> shapes = ShapeIndices;
if(shapes != null)
{
for(int shp = 0; shp < shapes.Count; shp++)
{
if (!shapes[shp].Intersects(aoi)) continue;
IFeature f = GetFeature(shp);
affected.ExpandToInclude(shapes[shp].Extent);
result.Add(f);
}
}
affectedRegion = affected.ToEnvelope();
return result;
}
affectedRegion = new Envelope();
foreach (IFeature feature in Features)
{
if (!feature.Envelope.Intersects(region)) continue;
result.Add(feature);
affectedRegion.ExpandToInclude(feature.Envelope);
}
return result;
}
/// <summary>
/// Obtains a typed list of ShapefilePoint structures with double values associated with the various coordinates.
/// </summary>
/// <param name="filename">A string filename</param>
/// <param name="progressHandler">A progress indicator</param>
private void FillPoints(string filename, IProgressHandler progressHandler)
{
// Check to ensure the filename is not null
if (filename == null)
{
throw new NullReferenceException(MessageStrings.ArgumentNull_S.Replace("%S",filename));
}
if (File.Exists(filename) == false)
{
throw new FileNotFoundException(MessageStrings.FileNotFound_S.Replace("%S", filename));
}
// Reading the headers gives us an easier way to track the number of shapes and their overall length etc.
List<ShapeHeader> shapeHeaders = ReadIndexFile(filename);
// Get the basic header information.
ShapefileHeader header = new ShapefileHeader(filename);
Extent = new Extent(new[] { header.Xmin, header.Ymin, header.Xmax, header.Ymax });
Envelope = Extent.ToEnvelope();
// Check to ensure that the filename is the correct shape type
if (header.ShapeType != ShapeTypes.Point && header.ShapeType != ShapeTypes.PointM && header.ShapeType != ShapeTypes.PointZ)
{
throw new ApplicationException(MessageStrings.FileNotPoints_S.Replace("%S", filename));
}
// This will set up a reader so that we can read values in huge chunks, which is much faster than one value at a time.
IO.BufferedBinaryReader bbReader = new IO.BufferedBinaryReader(filename, progressHandler);
if (bbReader.FileLength == 100)
{
bbReader.Close();
// the file is empty so we are done reading
return;
}
// Skip the shapefile header by skipping the first 100 bytes in the shapefile
bbReader.Seek(100, SeekOrigin.Begin);
int numShapes = shapeHeaders.Count;
byte[] bigEndian = new byte[numShapes * 8];
byte[] allCoords = new byte[numShapes * 16];
bool isM = false;
bool isZ = false;
if(header.ShapeType == ShapeTypes.PointM || header.ShapeType == ShapeTypes.PointZ)
{
isM = true;
}
if (header.ShapeType == ShapeTypes.PointZ)
{
isZ = true;
}
byte[] allM = new byte[8];
if(isM) allM = new byte[numShapes * 8];
byte[] allZ = new byte[8];
if(isZ) allZ = new byte[numShapes * 8];
for (int shp = 0; shp < numShapes; shp++)
{
// Read from the index file because some deleted records
// might still exist in the .shp file.
long offset = (shapeHeaders[shp].ByteOffset);
bbReader.Seek(offset, SeekOrigin.Begin);
bbReader.Read(bigEndian, shp * 8, 8);
ShapeTypes type = (ShapeTypes)bbReader.ReadInt32();
//bbReader.Seek(4, SeekOrigin.Current);
bbReader.Read(allCoords, shp * 16, 16);
if(isZ)
{
bbReader.Read(allZ, shp*8, 8);
}
if (isM)
{
bbReader.Read(allM, shp*8, 8);
}
ShapeRange shape = new ShapeRange(FeatureTypes.Point);
shape.StartIndex = shp;
shape.ContentLength = 8;
shape.NumPoints = 1;
shape.NumParts = 1;
ShapeIndices.Add(shape);
}
double[] vert = new double[2 * numShapes];
Buffer.BlockCopy(allCoords, 0, vert, 0, numShapes*16);
Vertex = vert;
if(isM)
{
double[] m = new double[numShapes];
Buffer.BlockCopy(allM, 0, m, 0, numShapes * 8);
M = m;
}
if(isZ)
{
double[] z = new double[numShapes];
Buffer.BlockCopy(allZ, 0, z, 0, numShapes * 8);
Z = z;
}
for (int shp = 0; shp < numShapes; shp++)
{
PartRange part = new PartRange(vert, shp, 0, FeatureTypes.Point);
part.NumVertices = 1;
ShapeRange shape = ShapeIndices[shp];
shape.Parts.Add(part);
shape.Extent = new Extent(new[] {vert[shp*2], vert[shp*2 + 1], vert[shp*2], vert[shp*2 + 1]});
}
bbReader.Dispose();
}
/// <summary>
/// Tests to see if any vertices from the other shape are coincident with a segment from this line shape.
/// </summary>
/// <param name="lineShape"></param>
/// <param name="otherShape"></param>
/// <returns></returns>
public static bool IntersectsVertex(ShapeRange lineShape, ShapeRange otherShape)
{
foreach (PartRange part in lineShape.Parts)
{
foreach (Segment segment in part.Segments)
{
foreach (PartRange oPart in otherShape.Parts)
{
foreach (Vertex v in oPart)
{
if(segment.IntersectsVertex(v)) return true;
}
}
}
}
return false;
}
/// <summary>
/// Returns true if any segment from a line or polygon shape interesect any segments from the line or polygon shape.
/// </summary>
/// <param name="lineShape">A Line or Polygon shape</param>
/// <param name="otherShape">Another line or polygon shape</param>
/// <returns></returns>
public static bool SegmentsIntersect(ShapeRange lineShape, ShapeRange otherShape)
{
if(lineShape.FeatureType != FeatureTypes.Line && lineShape.FeatureType != FeatureTypes.Polygon)
throw new ArgumentException("Expected lineShape to be a line or polygon feature type, got " + lineShape.FeatureType);
if (otherShape.FeatureType != FeatureTypes.Line && otherShape.FeatureType != FeatureTypes.Polygon)
throw new ArgumentException("Expected otherShape to be a line or polygon feature type, got " + otherShape.FeatureType);
foreach (PartRange part in lineShape.Parts)
{
foreach (Segment segment in part.Segments)
{
foreach (PartRange oPart in otherShape.Parts)
{
int iSeg = 0;
foreach (Segment oSegment in oPart.Segments)
{
iSeg++;
if(iSeg == 279)
{
bool stop = true;
}
if (segment.Intersects(oSegment))
{
return true;
}
}
}
}
}
// If the other segment is a polygon, we need to check the "
return false;
}
// X Y MultiPoints: Total Length = 28 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 8 Integer 1 Little
// Byte 12 Xmin Double 1 Little
// Byte 20 Ymin Double 1 Little
// Byte 28 Xmax Double 1 Little
// Byte 36 Ymax Double 1 Little
// Byte 48 NumPoints Integer 1 Little
// Byte X Points Point NumPoints Little
// X Y M MultiPoints: Total Length = 34 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 28 Integer 1 Little
// Byte 12 Box Double 4 Little
// Byte 44 NumPoints Integer 1 Little
// Byte X Points Point NumPoints Little
// Byte Y* Mmin Double 1 Little
// Byte Y + 8* Mmax Double 1 Little
// Byte Y + 16* Marray Double NumPoints Little
// X Y Z M MultiPoints: Total Length = 44 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 18 Integer 1 Little
// Byte 12 Box Double 4 Little
// Byte 44 NumPoints Integer 1 Little
// Byte X Points Point NumPoints Little
// Byte Y Zmin Double 1 Little
// Byte Y + 8 Zmax Double 1 Little
// Byte Y + 16 Zarray Double NumPoints Little
// Byte Z* Mmin Double 1 Little
// Byte Z+8* Mmax Double 1 Little
// Byte Z+16* Marray Double NumPoints Little
private void FillPoints(string filename, IProgressHandler progressHandler)
{
// Check to ensure the filename is not null
if (filename == null)
{
throw new NullReferenceException(MessageStrings.ArgumentNull_S.Replace("%S", filename));
}
if (File.Exists(filename) == false)
{
throw new FileNotFoundException(MessageStrings.FileNotFound_S.Replace("%S", filename));
}
// Get the basic header information.
ShapefileHeader header = new ShapefileHeader(filename);
Extent = new Extent(new[] { header.Xmin, header.Ymin, header.Xmax, header.Ymax });
// Check to ensure that the filename is the correct shape type
if (header.ShapeType != ShapeTypes.MultiPoint &&
header.ShapeType != ShapeTypes.MultiPointM &&
header.ShapeType != ShapeTypes.MultiPointZ)
{
throw new ArgumentException(MessageStrings.FileNotLines_S.Replace("%S", filename));
}
// Reading the headers gives us an easier way to track the number of shapes and their overall length etc.
List<ShapeHeader> shapeHeaders = ReadIndexFile(filename);
// This will set up a reader so that we can read values in huge chunks, which is much faster than one value at a time.
IO.BufferedBinaryReader bbReader = new IO.BufferedBinaryReader(filename, progressHandler);
if (bbReader.FileLength == 100)
{
// The shapefile is empty so we can simply return here
bbReader.Close();
return;
}
// Skip the shapefile header by skipping the first 100 bytes in the shapefile
bbReader.Seek(100, SeekOrigin.Begin);
int numShapes = shapeHeaders.Count;
byte[] bigEndians = new byte[numShapes * 8];
byte[] allBounds = new byte[numShapes * 32];
ByteBlock allCoords = new ByteBlock(BLOCKSIZE);
bool isM = (header.ShapeType == ShapeTypes.MultiPointZ || header.ShapeType == ShapeTypes.MultiPointM);
bool isZ = (header.ShapeType == ShapeTypes.PolyLineZ);
ByteBlock allZ = null;
ByteBlock allM = null;
if (isZ)
{
allZ = new ByteBlock(BLOCKSIZE);
}
if (isM)
{
allM = new ByteBlock(BLOCKSIZE);
}
int pointOffset = 0;
for (int shp = 0; shp < numShapes; shp++)
{
// Read from the index file because some deleted records
// might still exist in the .shp file.
long offset = (shapeHeaders[shp].ByteOffset);
bbReader.Seek(offset, SeekOrigin.Begin);
// time: 200 ms
ShapeRange shape = new ShapeRange(FeatureTypes.MultiPoint);
shape.RecordNumber = bbReader.ReadInt32(false); // Byte 0 Record Number Integer 1 Big
shape.ContentLength = bbReader.ReadInt32(false); // Byte 4 Content Length Integer 1 Big
//bbReader.Read(bigEndians, shp * 8, 8);
shape.ShapeType = (ShapeTypes)bbReader.ReadInt32();
shape.StartIndex = pointOffset;
if (shape.ShapeType == ShapeTypes.NullShape)
{
continue;
}
bbReader.Read(allBounds, shp * 32, 32);
shape.NumParts = 1;
shape.NumPoints = bbReader.ReadInt32();
allCoords.Read(shape.NumPoints * 16, bbReader);
pointOffset += shape.NumPoints;
if (header.ShapeType == ShapeTypes.MultiPointM)
{
// These are listed as "optional" but there isn't a good indicator of how to determine if they were added.
// To handle the "optional" M values, check the contentLength for the feature.
// The content length does not include the 8-byte record header and is listed in 16-bit words.
if (shape.ContentLength * 2 > 44 + 4 * shape.NumParts + 16 * shape.NumPoints)
{
double mMin = bbReader.ReadDouble();
double mMax = bbReader.ReadDouble();
//bbReader.Seek(16, SeekOrigin.Current);
if (allM != null) allM.Read(shape.NumPoints * 8, bbReader);
}
}
if (header.ShapeType == ShapeTypes.MultiPointZ)
{
bool hasM = shape.ContentLength * 2 > 60 + 4 * shape.NumParts + 24 * shape.NumPoints;
double zMin = bbReader.ReadDouble();
double zMax = bbReader.ReadDouble();
// For Z shapefiles, the Z part is not optional.
if (allZ != null) allZ.Read(shape.NumPoints * 8, bbReader);
// These are listed as "optional" but there isn't a good indicator of how to determine if they were added.
// To handle the "optional" M values, check the contentLength for the feature.
// The content length does not include the 8-byte record header and is listed in 16-bit words.
if (hasM)
{
double mMin = bbReader.ReadDouble();
double mMax = bbReader.ReadDouble();
if (allM != null) allM.Read(shape.NumPoints * 8, bbReader);
}
}
// Now that we have read all the values, create the geometries from the points and parts arrays.
ShapeIndices.Add(shape);
}
double[] vert = allCoords.ToDoubleArray();
Vertex = vert;
if (isM) M = allM.ToDoubleArray();
if (isZ) Z = allZ.ToDoubleArray();
Array.Reverse(bigEndians);
List<ShapeRange> shapes = ShapeIndices;
double[] bounds = new double[numShapes * 4];
Buffer.BlockCopy(allBounds, 0, bounds, 0, allBounds.Length);
for (int shp = 0; shp < numShapes; shp++)
{
ShapeRange shape = shapes[shp];
shape.Extent = new Extent(bounds, shp * 4);
int endIndex = shape.NumPoints + shape.StartIndex;
int startIndex = shape.StartIndex;
int count = endIndex - startIndex;
PartRange partR = new PartRange(vert, shape.StartIndex, 0, FeatureTypes.MultiPoint);
partR.NumVertices = count;
shape.Parts.Add(partR);
}
GC.Collect();
bbReader.Dispose();
}
/// <summary>
/// This cycles through all the vertices, which are stored as {X1, Y1, X2, Y2...Xn, Yn} and tests
/// if any of those vertices falls within the polygon shape.
/// </summary>
/// <param name="polygonShape"></param>
/// <param name="otherShape"></param>
/// <returns></returns>
public static bool ContainsVertex(ShapeRange polygonShape, ShapeRange otherShape)
{
foreach (PartRange otherPart in otherShape.Parts)
{
if(ContainsVertex(polygonShape, otherPart))
{
return true;
}
}
return false;
}
/// <summary>
/// Appends the specified polygon to the graphics path.
/// </summary>
private static void BuildPolygon(double[] vertices, ShapeRange shpx, GraphicsPath borderPath, MapArgs args, bool clip)
{
double minX = args.MinX;
double maxY = args.MaxY;
double dx = args.Dx;
double dy = args.Dy;
borderPath.FillMode = FillMode.Winding;
for (int prt = 0; prt < shpx.Parts.Count; prt++)
{
PartRange prtx = shpx.Parts[prt];
int start = prtx.StartIndex;
int end = prtx.EndIndex;
List<double[]> points = new List<double[]>();
for (int i = start; i <= end; i++)
{
double[] pt = new double[2];
pt[X] = (vertices[i * 2] - minX) * dx;
pt[Y] = (maxY - vertices[i*2+1]) * dy;
points.Add(pt);
}
if (clip)
{
points = SoutherlandHodgman.Clip(points);
}
List<System.Drawing.Point> intPoints = DuplicationPreventer.Clean(points);
if (intPoints.Count < 2)
{
points.Clear();
continue;
}
borderPath.StartFigure();
System.Drawing.Point[] pointArray = intPoints.ToArray();
borderPath.AddLines(pointArray);
points.Clear();
}
}
private static void FastBuildLine(GraphicsPath graphPath, double[] vertices, ShapeRange shpx, double minX, double maxY, double dx, double dy)
{
for (int prt = 0; prt < shpx.Parts.Count; prt++)
{
PartRange prtx = shpx.Parts[prt];
int start = prtx.StartIndex;
int end = prtx.EndIndex;
List<System.Drawing.Point> partPoints = new List<System.Drawing.Point>();
System.Drawing.Point previousPoint = new System.Drawing.Point();
for (int i = start; i <= end; i++)
{
if (double.IsNaN(vertices[i*2]) || double.IsNaN(vertices[i * 2 + 1])) continue;
System.Drawing.Point pt = new System.Drawing.Point();
pt.X = Convert.ToInt32((vertices[i * 2] - minX) * dx);
pt.Y = Convert.ToInt32((maxY - vertices[i * 2 + 1]) * dy);
if (i == 0 || (pt.X != previousPoint.X || pt.Y != previousPoint.Y))
{
// Don't add the same point twice
partPoints.Add(pt);
previousPoint = pt;
}
}
if (partPoints.Count < 2) continue; // we need two distinct points to make a line
graphPath.StartFigure();
graphPath.AddLines(partPoints.ToArray());
}
}
/// <summary>
/// This assumes that the byte order and shapetype have already been read.
/// </summary>
/// <param name="data"></param>
/// <param name="results"></param>
private static void ReadPoint(Stream data, FeatureSetPack results)
{
ShapeRange sr = new ShapeRange(FeatureTypes.MultiPoint);
PartRange prt = new PartRange(FeatureTypes.MultiPoint);
prt.NumVertices = 1;
sr.Parts.Add(prt);
double[] coord = ReadDouble(data, 2);
results.Add(coord, sr);
}
/// <summary>
/// This calculations processes the intersections
/// </summary>
/// <param name="shape">The shape to do intersection calculations with.</param>
public bool Intersects(ShapeRange shape)
{
// Extent check first. If the extents don't intersect, then this doesn't intersect.
if (!Extent.Intersects(shape.Extent)) return false;
switch (FeatureType)
{
case FeatureTypes.Polygon:
PolygonShape.Epsilon = Epsilon;
return PolygonShape.Intersects(this, shape);
case FeatureTypes.Line:
LineShape.Epsilon = Epsilon;
return LineShape.Intersects(this, shape);
case FeatureTypes.Point:
PointShape.Epsilon = Epsilon;
return PointShape.Intersects(this, shape);
default:
return false;
}
}
private static void ReadMultiPoint(Stream data, FeatureSetPack results)
{
int count = ReadInt32(data);
ShapeRange sr = new ShapeRange(FeatureTypes.MultiPoint);
PartRange prt = new PartRange(FeatureTypes.MultiPoint);
prt.NumVertices = count;
sr.Parts.Add(prt);
double[] vertices = new double[count*2];
for(int iPoint = 0; iPoint < count; iPoint++)
{
data.ReadByte(); // ignore endian
ReadInt32(data); // ignore geometry type
double[] coord = ReadDouble(data, 2);
Array.Copy(coord, 0, vertices, iPoint*2, 2);
}
results.Add(vertices, sr);
}
/// <summary>
/// Occurs when the vertices are being re-calculated.
/// </summary>
protected virtual void OnInitializeVertices()
{
int count = 0;
foreach (IFeature f in _features)
{
count += f.NumPoints;
}
_vertices = new double[count*2];
int i = 0;
foreach(IFeature f in _features)
{
IList<Coordinate> coords = f.Coordinates; // this should be all the coordinates, for all parts of the geometry.
if (coords == null) continue;
foreach (Coordinate c in coords)
{
_vertices[i*2] = c.X;
_vertices[i*2+1] = c.Y;
// vertexValues.Add(c.Values); // essentially add a reference pointer to the internal array of values
i++;
}
}
//_vertices = vertexValues.ToArray(); // not sure, but I bet arrays a smidge faster at indexed access than lists
_shapeIndices = new List<ShapeRange>();
int vIndex = 0;
for(int shp = 0; shp < _features.Count; shp++)
{
IFeature f = _features[shp];
ShapeRange shx = new ShapeRange(FeatureType);
shx.Extent = new Extent(f.Envelope);
_shapeIndices.Add(shx);
f.ShapeIndex = shx;
// for simplicity in looping, there is always at least one part.
// That way, the shape range can be ignored and the parts loop used instead.
shx.Parts = new List<PartRange>();
int shapeStart = vIndex;
for (int part = 0; part < f.NumGeometries; part++)
{
PartRange prtx = new PartRange(_vertices, shapeStart, vIndex-shapeStart, FeatureType);
IBasicPolygon bp = f.GetBasicGeometryN(part) as IBasicPolygon;
if(bp != null)
{
// Account for the Shell
prtx.NumVertices = bp.Shell.NumPoints;
vIndex += bp.Shell.NumPoints;
// The part range should be adjusted to no longer include the holes
foreach (var hole in bp.Holes)
{
PartRange holex = new PartRange(_vertices, shapeStart, vIndex - shapeStart, FeatureType);
holex.NumVertices = hole.NumPoints;
shx.Parts.Add(holex);
vIndex += hole.NumPoints;
}
}
else
{
int numPoints = f.GetBasicGeometryN(part).NumPoints;
// This is not a polygon, so just add the number of points.
vIndex += numPoints;
prtx.NumVertices = numPoints;
}
shx.Parts.Add(prtx);
}
}
// _vertices = vertexValues.ToArray();
_verticesAreValid = true;
}
private static void ReadLineString(Stream data, FeatureSetPack results)
{
int count = ReadInt32(data);
double[] coords = ReadDouble(data, 2 * count);
ShapeRange lShp = new ShapeRange(FeatureTypes.Line);
PartRange lPrt = new PartRange(FeatureTypes.Line);
lPrt.NumVertices = count;
lShp.Parts.Add(lPrt);
results.Add(coords, lShp);
}
private static void ReadMultiLineString(Stream data, FeatureSetPack results)
{
int numLineStrings = ReadInt32(data);
ShapeRange shp = new ShapeRange(FeatureTypes.Line);
List<double[]> strings = new List<double[]>();
int partOffset = 0;
for(int iString = 0; iString < numLineStrings; iString++)
{
// Each of these needs to read a full WKBLineString
data.Seek(5, SeekOrigin.Current); //ignore header
int numPoints = ReadInt32(data);
double[] coords = ReadDouble(data, 2*numPoints);
PartRange lPrt = new PartRange(FeatureTypes.Line);
lPrt.PartOffset = partOffset;
lPrt.NumVertices = numPoints;
shp.Parts.Add(lPrt);
partOffset += coords.Length/2;
strings.Add(coords);
}
double[] allVertices = new double[partOffset * 2];
int offset = 0;
foreach (double[] ring in strings)
{
Array.Copy(ring, 0, allVertices, offset, ring.Length);
offset += ring.Length;
}
results.Add(allVertices, shp);
}
// X Y Poly Lines: Total Length = 28 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 3 Integer 1 Little
// Byte 12 Xmin Double 1 Little
// Byte 20 Ymin Double 1 Little
// Byte 28 Xmax Double 1 Little
// Byte 36 Ymax Double 1 Little
// Byte 44 NumParts Integer 1 Little
// Byte 48 NumPoints Integer 1 Little
// Byte 52 Parts Integer NumParts Little
// Byte X Points Point NumPoints Little
// X Y M Poly Lines: Total Length = 34 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 23 Integer 1 Little
// Byte 12 Box Double 4 Little
// Byte 44 NumParts Integer 1 Little
// Byte 48 NumPoints Integer 1 Little
// Byte 52 Parts Integer NumParts Little
// Byte X Points Point NumPoints Little
// Byte Y* Mmin Double 1 Little
// Byte Y + 8* Mmax Double 1 Little
// Byte Y + 16* Marray Double NumPoints Little
// X Y Z M Poly Lines: Total Length = 44 Bytes
// ---------------------------------------------------------
// Position Value Type Number Byte Order
// ---------------------------------------------------------
// Byte 0 Record Number Integer 1 Big
// Byte 4 Content Length Integer 1 Big
// Byte 8 Shape Type 13 Integer 1 Little
// Byte 12 Box Double 4 Little
// Byte 44 NumParts Integer 1 Little
// Byte 48 NumPoints Integer 1 Little
// Byte 52 Parts Integer NumParts Little
// Byte X Points Point NumPoints Little
// Byte Y Zmin Double 1 Little
// Byte Y + 8 Zmax Double 1 Little
// Byte Y + 16 Zarray Double NumPoints Little
// Byte Z* Mmin Double 1 Little
// Byte Z+8* Mmax Double 1 Little
// Byte Z+16* Marray Double NumPoints Little
private void FillPolygons(string filename, IProgressHandler progressHandler)
{
// Check to ensure the filename is not null
if (filename == null)
{
throw new NullReferenceException(MessageStrings.ArgumentNull_S.Replace("%S", filename));
}
if (File.Exists(filename) == false)
{
throw new FileNotFoundException(MessageStrings.FileNotFound_S.Replace("%S", filename));
}
// Get the basic header information.
ShapefileHeader header = new ShapefileHeader(filename);
Extent = new Extent(new[]{header.Xmin, header.Ymin, header.Xmax, header.Ymax});
// Check to ensure that the filename is the correct shape type
if (header.ShapeType != ShapeTypes.Polygon &&
header.ShapeType != ShapeTypes.PolygonM &&
header.ShapeType != ShapeTypes.PolygonZ)
{
throw new ArgumentException(MessageStrings.FileNotLines_S.Replace("%S", filename));
}
// Reading the headers gives us an easier way to track the number of shapes and their overall length etc.
List<ShapeHeader> shapeHeaders = ReadIndexFile(filename);
// This will set up a reader so that we can read values in huge chunks, which is much faster than one value at a time.
IO.BufferedBinaryReader bbReader = new IO.BufferedBinaryReader(filename, progressHandler);
if (bbReader.FileLength == 100)
{
// The shapefile is empty so we can simply return here
bbReader.Close();
return;
}
// Skip the shapefile header by skipping the first 100 bytes in the shapefile
bbReader.Seek(100, SeekOrigin.Begin);
int numShapes = shapeHeaders.Count;
int [] partOffsets = new int[numShapes];
byte[] bigEndians = new byte[numShapes * 8];
byte[] allBounds = new byte[numShapes * 32];
ByteBlock allParts = new ByteBlock(BLOCKSIZE); // probably all will be in one block, but use a byteBlock just in case.
ByteBlock allCoords = new ByteBlock(BLOCKSIZE);
bool isM = (header.ShapeType == ShapeTypes.PolyLineM || header.ShapeType == ShapeTypes.PolyLineZ);
bool isZ = (header.ShapeType == ShapeTypes.PolyLineZ);
ByteBlock allZ = null;
ByteBlock allM = null;
if (isZ)
{
allZ = new ByteBlock(BLOCKSIZE);
}
if (isM)
{
allM = new ByteBlock(BLOCKSIZE);
}
int pointOffset = 0;
for (int shp = 0; shp < numShapes; shp++)
{
// Read from the index file because some deleted records
// might still exist in the .shp file.
long offset = (shapeHeaders[shp].ByteOffset);
bbReader.Seek(offset, SeekOrigin.Begin);
// Position Value Type Number Byte Order
ShapeRange shape = new ShapeRange(FeatureTypes.Polygon); //--------------------------------------------------------------------
shape.RecordNumber = bbReader.ReadInt32(false); // Byte 0 Record Number Integer 1 Big
shape.ContentLength = bbReader.ReadInt32(false); // Byte 4 Content Length Integer 1 Big
shape.ShapeType = (ShapeTypes)bbReader.ReadInt32(); // Byte 8 Shape Type Integer 1 Little
shape.StartIndex = pointOffset;
if (shape.ShapeType == ShapeTypes.NullShape)
{
continue;
}
bbReader.Read(allBounds, shp*32, 32);
//double xMin = bbReader.ReadDouble(); // Byte 12 Xmin Double 1 Little
// double yMin = bbReader.ReadDouble(); // Byte 20 Ymin Double 1 Little
//double xMax = bbReader.ReadDouble(); // Byte 28 Xmax Double 1 Little
//double yMax = bbReader.ReadDouble(); // Byte 36 Ymax Double 1 Little
shape.NumParts = bbReader.ReadInt32(); // Byte 44 NumParts Integer 1 Little
//feature.NumPoints = bbReader.ReadInt32(); // Byte 48 NumPoints Integer 1 Little
shape.NumPoints = bbReader.ReadInt32();
// Create an envelope from the extents box in the file.
//feature.Envelope = new Envelope(xMin, xMax, yMin, yMax);
partOffsets[shp] = allParts.IntOffset();
allParts.Read(shape.NumParts * 4, bbReader);
allCoords.Read(shape.NumPoints * 16, bbReader);
pointOffset += shape.NumPoints;
if (header.ShapeType == ShapeTypes.PolygonM)
{
// These are listed as "optional" but there isn't a good indicator of how to determine if they were added.
// To handle the "optional" M values, check the contentLength for the feature.
// The content length does not include the 8-byte record header and is listed in 16-bit words.
if (shape.ContentLength * 2 > 44 + 4 * shape.NumParts + 16 * shape.NumPoints)
{
double mMin = bbReader.ReadDouble();
double mMax = bbReader.ReadDouble();
if(allM != null)allM.Read(shape.NumPoints * 8, bbReader);
}
}
if (header.ShapeType == ShapeTypes.PolygonZ)
{
bool hasM = shape.ContentLength * 2 > 60 + 4 * shape.NumParts + 24 * shape.NumPoints;
double zMin = bbReader.ReadDouble();
double zMax = bbReader.ReadDouble();
// For Z shapefiles, the Z part is not optional.
if (allZ != null) allZ.Read(shape.NumPoints * 8, bbReader);
// These are listed as "optional" but there isn't a good indicator of how to determine if they were added.
// To handle the "optional" M values, check the contentLength for the feature.
// The content length does not include the 8-byte record header and is listed in 16-bit words.
if (hasM)
{
double mMin = bbReader.ReadDouble();
double mMax = bbReader.ReadDouble();
if (allM != null) allM.Read(shape.NumPoints * 8, bbReader);
}
}
ShapeIndices.Add(shape);
}
double[] vert = allCoords.ToDoubleArray();
Vertex = vert;
if (isM) M = allM.ToDoubleArray();
if (isZ) Z = allZ.ToDoubleArray();
List<ShapeRange> shapes = ShapeIndices;
double[] bounds = new double[numShapes * 4];
Buffer.BlockCopy(allBounds, 0, bounds, 0, allBounds.Length);
int[] parts = allParts.ToIntArray();
ProgressMeter = new ProgressMeter(ProgressHandler, "Testing Parts and Holes", numShapes);
for (int shp = 0; shp < numShapes; shp++)
{
ShapeRange shape = shapes[shp];
shape.Extent = new Extent(bounds, shp * 4);
for (int part = 0; part < shape.NumParts; part++)
{
int offset = partOffsets[shp];
int endIndex = shape.NumPoints + shape.StartIndex;
int startIndex = parts[offset + part] + shape.StartIndex;
if (part < shape.NumParts - 1) endIndex = parts[offset + part + 1] + shape.StartIndex;
int count = endIndex - startIndex;
PartRange partR = new PartRange(vert, shape.StartIndex, parts[offset + part], FeatureTypes.Polygon);
partR.NumVertices = count;
shape.Parts.Add(partR);
}
ProgressMeter.CurrentValue = shp;
}
ProgressMeter.Reset();
GC.Collect();
}
