/// <summary>
/// Read a shapefile Point record.
/// </summary>
/// <param name="stream">Input stream.</param>
/// <param name="record">Shapefile record to be updated.</param>
private static void ReadPoint(Stream stream, ShapeFileRecord record)
{
// Points - add a single point.
Point p = new System.Windows.Point();
p.X = ShapeFile.ReadDouble64_LE(stream);
p.Y = ShapeFile.ReadDouble64_LE(stream);
record.Points.Add(p);
// Bounding Box.
record.XMin = p.X;
record.YMin = p.Y;
record.XMax = record.XMin;
record.YMax = record.YMin;
}
/// <summary>
/// Read a shapefile Polygon record.
/// </summary>
/// <param name="stream">Input stream.</param>
/// <param name="record">Shapefile record to be updated.</param>
private static void ReadPolygon(Stream stream, ShapeFileRecord record)
{
// Bounding Box.
record.XMin = ShapeFile.ReadDouble64_LE(stream);
record.YMin = ShapeFile.ReadDouble64_LE(stream);
record.XMax = ShapeFile.ReadDouble64_LE(stream);
record.YMax = ShapeFile.ReadDouble64_LE(stream);
// Num Parts and Points.
int numParts = ShapeFile.ReadInt32_LE(stream);
int numPoints = ShapeFile.ReadInt32_LE(stream);
// Parts.
for (int i = 0; i < numParts; i++)
{
record.Parts.Add(ShapeFile.ReadInt32_LE(stream));
}
// Points.
for (int i = 0; i < numPoints; i++)
{
Point p = new Point();
p.X = ShapeFile.ReadDouble64_LE(stream);
p.Y = ShapeFile.ReadDouble64_LE(stream);
record.Points.Add(p);
}
}
/// <summary>
/// Read a shapefile record.
/// </summary>
/// <param name="stream">Input stream.</param>
public ShapeFileRecord ReadShapeFileRecord(Stream stream)
{
ShapeFileRecord record = new ShapeFileRecord();
// Record Header.
record.RecordNumber = ShapeFile.ReadInt32_BE(stream);
record.ContentLength = ShapeFile.ReadInt32_BE(stream);
// Shape Type.
record.ShapeType = ShapeFile.ReadInt32_LE(stream);
// Read the shape geometry, depending on its type.
switch (record.ShapeType)
{
case (int)ShapeType.NullShape:
// Do nothing.
break;
case (int)ShapeType.Point:
ShapeFile.ReadPoint(stream, record);
break;
case (int)ShapeType.PolyLine:
// PolyLine has exact same structure as Polygon in shapefile.
ShapeFile.ReadPolygon(stream, record);
break;
case (int)ShapeType.Polygon:
ShapeFile.ReadPolygon(stream, record);
break;
case (int)ShapeType.Multipoint:
ShapeFile.ReadMultipoint(stream, record);
break;
default:
{
string msg = String.Format(System.Globalization.CultureInfo.InvariantCulture, "ShapeType {0} is not supported.", (int)record.ShapeType);
throw new FileFormatException(msg);
}
}
// Add the record to our internal list.
this.records.Add(record);
return record;
}
/// <summary>
/// Create a WPF shape given a shapefile record.
/// </summary>
/// <param name="shapeName">The name of the WPF shape.</param>
/// <param name="record">Shapefile record.</param>
/// <returns>The created WPF shape.</returns>
private Shape CreateWPFShape(string shapeName, ShapeFileRecord record)
{
// Create a new geometry.
Geometry geometry;
if ( this.geometryType == GeometryType.UsePathGeometry )
geometry = this.CreatePathGeometry(record);
else
geometry = this.CreateStreamGeometry(record);
// Transform the geometry based on current zoom and pan settings.
geometry.Transform = this.viewTransform;
// Create a new WPF Path.
System.Windows.Shapes.Path path = new System.Windows.Shapes.Path();
// Assign the geometry to the path and set its name.
path.Data = geometry;
path.Name = shapeName;
// Set path properties.
path.StrokeThickness = 0.5;
if ( record.ShapeType == (int)ShapeType.Polygon )
{
path.Stroke = this.strokeBrush;
path.Fill = this.GetRandomShapeBrush();
}
else
{
path.Stroke = Brushes.DimGray;
}
// Return the created WPF shape.
return path;
}
/// <summary>
/// Create a WPF shape to represent a shapefile point or
/// multipoint record.
/// </summary>
/// <param name="shapeName">The name of the WPF shape.</param>
/// <param name="record">Shapefile record.</param>
/// <returns>The created WPF shape.</returns>
private Shape CreateWPFPoint(string shapeName, ShapeFileRecord record)
{
// Create a new geometry.
GeometryGroup geometry = new GeometryGroup();
// Add ellipse geometries to the group.
foreach (Point pt in record.Points)
{
// Create a new ellipse geometry.
EllipseGeometry ellipseGeo = new EllipseGeometry();
// Transform center point of the ellipse from lon/lat to
// canvas coordinates.
ellipseGeo.Center = this.shapeTransform.Transform(pt);
// Set the size of the ellipse.
ellipseGeo.RadiusX = 0.1;
ellipseGeo.RadiusY = 0.1;
// Add the ellipse to the geometry group.
geometry.Children.Add(ellipseGeo);
}
// Transform the geometry based on current zoom and pan settings.
geometry.Transform = this.viewTransform;
// Add the geometry to a new Path and set path properties.
System.Windows.Shapes.Path path = new System.Windows.Shapes.Path();
path.Data = geometry;
path.Name = shapeName;
path.Fill = Brushes.Crimson;
path.StrokeThickness = 1;
path.Stroke = Brushes.DimGray;
// Return the created WPF shape.
return path;
}
/// <summary>
/// Create a StreamGeometry given a shapefile record.
/// </summary>
/// <param name="record">Shapefile record.</param>
/// <returns>A StreamGeometry instance.</returns>
private Geometry CreateStreamGeometry(ShapeFileRecord record)
{
// Create a new stream geometry.
StreamGeometry geometry = new StreamGeometry();
// Obtain the stream geometry context for drawing each part.
using (StreamGeometryContext ctx = geometry.Open())
{
// Draw figures.
for (int i = 0; i < record.NumberOfParts; i++)
{
// Determine the starting index and the end index
// into the points array that defines the figure.
int start = record.Parts[i];
int end;
if (record.NumberOfParts > 1 && i != (record.NumberOfParts - 1))
end = record.Parts[i + 1];
else
end = record.NumberOfPoints;
// Draw the figure.
for (int j = start; j < end; j++)
{
System.Windows.Point pt = record.Points[j];
// Transform from lon/lat to canvas coordinates.
pt = this.shapeTransform.Transform(pt);
// Decide if the line segments are stroked or not. For the
// PolyLine type it must be stroked.
bool isStroked = (record.ShapeType == (int)ShapeType.PolyLine) || !(this.geometryType == GeometryType.UseStreamGeometryNotStroked);
// Register the drawing instruction.
if (j == start)
ctx.BeginFigure(pt, true, false);
else
ctx.LineTo(pt, isStroked, true);
}
}
}
// Return the created stream geometry.
return geometry;
}
/// <summary>
/// Create a PathGeometry given a shapefile record.
/// </summary>
/// <param name="record">Shapefile record.</param>
/// <returns>A PathGeometry instance.</returns>
private Geometry CreatePathGeometry(ShapeFileRecord record)
{
// Create a new geometry.
PathGeometry geometry = new PathGeometry();
// Add figures to the geometry.
for (int i = 0; i < record.NumberOfParts; i++)
{
// Create a new path figure.
PathFigure figure = new PathFigure();
// Determine the starting index and the end index
// into the points array that defines the figure.
int start = record.Parts[i];
int end;
if (record.NumberOfParts > 1 && i != (record.NumberOfParts - 1))
end = record.Parts[i + 1];
else
end = record.NumberOfPoints;
// Add line segments to the figure.
for (int j = start; j < end; j++)
{
System.Windows.Point pt = record.Points[j];
// Transform from lon/lat to canvas coordinates.
pt = this.shapeTransform.Transform(pt);
if (j == start)
figure.StartPoint = pt;
else
figure.Segments.Add(new LineSegment(pt, true));
}
// Add the new figure to the geometry.
geometry.Figures.Add(figure);
}
// Return the created path geometry.
return geometry;
}