/// <summary>
/// Method to place the street direction symbols
/// </summary>
/// <param name="map"></param>
/// <param name="lineString"></param>
/// <param name="graphics"></param>
private void OnRenderInternal(SharpMap.MapViewport map, GeoAPI.Geometries.ILineString lineString,
System.Drawing.Graphics graphics)
{
var length = lineString.Length;
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(lineString);
if (length < RepeatInterval + ArrowLength)
{
var start = System.Math.Max(0, (length - ArrowLength) / 2);
var end = System.Math.Min(length, (length + ArrowLength) / 2);
var arrow = (GeoAPI.Geometries.ILineString)lil.ExtractLine(start, end);
RenderArrow(map, graphics, arrow);
return;
}
var numArrows = (int)((lineString.Length - ArrowLength) / RepeatInterval);
var offset = (lineString.Length - numArrows * RepeatInterval - ArrowLength) * 0.5;
while (offset + ArrowLength < lineString.Length)
{
var arrow = (GeoAPI.Geometries.ILineString)lil.ExtractLine(offset, offset + ArrowLength);
RenderArrow(map, graphics, arrow);
offset += RepeatInterval;
}
}
/// <summary>
/// Method to place the street direction symbols
/// </summary>
/// <param name="map"></param>
/// <param name="lineString"></param>
/// <param name="graphics"></param>
private void OnRenderInternal(SharpMap.Map map, GeoAPI.Geometries.ILineString lineString,
System.Drawing.Graphics graphics)
{
var length = lineString.Length;
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(lineString);
if (length < RepeatInterval + ArrowLength)
{
var start = System.Math.Max(0, (length - ArrowLength)/2);
var end = System.Math.Min(length, (length + ArrowLength)/2);
var arrow = (GeoAPI.Geometries.ILineString) lil.ExtractLine(start, end);
RenderArrow(map, graphics, arrow);
return;
}
var numArrows = (int) ((lineString.Length - ArrowLength)/RepeatInterval);
var offset = (lineString.Length - numArrows*RepeatInterval - ArrowLength)*0.5;
while (offset + ArrowLength < lineString.Length)
{
var arrow = (GeoAPI.Geometries.ILineString) lil.ExtractLine(offset, offset + ArrowLength);
RenderArrow(map, graphics, arrow);
offset += RepeatInterval;
}
}
public SharpMap.Geometries.MultiLineString SplitLineString(
SharpMap.Geometries.LineString lineString,
System.Double length)
{
if (lineString == null || lineString.IsEmpty())
throw new System.ArgumentException("Linestring is null or Empty", "lineString");
var gf = new NetTopologySuite.Geometries.GeometryFactory();
var ntsLine = (NetTopologySuite.Geometries.LineString)
SharpMap.Converters.NTS.GeometryConverter.ToNTSGeometry(lineString, gf);
var ret = new SharpMap.Geometries.MultiLineString();
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(ntsLine);
double currentLength = 0d;
while (currentLength < ntsLine.Length)
{
var tmpLine = (NetTopologySuite.Geometries.LineString)
lil.ExtractLine(currentLength, currentLength + length);
ret.LineStrings.Add((SharpMap.Geometries.LineString)
SharpMap.Converters.NTS.GeometryConverter.ToSharpMapGeometry(tmpLine));
currentLength += length;
}
return ret;
}
public GeoAPI.Geometries.IMultiLineString SplitLineString(
GeoAPI.Geometries.ILineString lineString,
System.Double length)
{
if (lineString == null || lineString.IsEmpty)
{
throw new System.ArgumentException("Linestring is null or Empty", "lineString");
}
//var gf = new NetTopologySuite.Geometries.GeometryFactory();
//var ntsLine = (NetTopologySuite.Geometries.LineString)
// SharpMap.Converters.NTS.GeometryConverter.ToNTSGeometry(lineString, gf);
var ret = new System.Collections.Generic.List <GeoAPI.Geometries.ILineString>();
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(lineString);
double currentLength = 0d;
while (currentLength < lineString.Length)
{
var tmpLine = (GeoAPI.Geometries.ILineString)
lil.ExtractLine(currentLength, currentLength + length);
ret.Add(tmpLine);
currentLength += length;
}
return(lineString.Factory.CreateMultiLineString(ret.ToArray()));
}
public SharpMap.Geometries.MultiLineString SplitLineString(
SharpMap.Geometries.LineString lineString,
System.Double length)
{
if (lineString == null || lineString.IsEmpty())
{
throw new System.ArgumentException("Linestring is null or Empty", "lineString");
}
var gf = new NetTopologySuite.Geometries.GeometryFactory();
var ntsLine = (NetTopologySuite.Geometries.LineString)
SharpMap.Converters.NTS.GeometryConverter.ToNTSGeometry(lineString, gf);
var ret = new SharpMap.Geometries.MultiLineString();
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(ntsLine);
double currentLength = 0d;
while (currentLength < ntsLine.Length)
{
var tmpLine = (NetTopologySuite.Geometries.LineString)
lil.ExtractLine(currentLength, currentLength + length);
ret.LineStrings.Add((SharpMap.Geometries.LineString)
SharpMap.Converters.NTS.GeometryConverter.ToSharpMapGeometry(tmpLine));
currentLength += length;
}
return(ret);
}
public GeoAPI.Geometries.IMultiLineString SplitLineString(
GeoAPI.Geometries.ILineString lineString,
System.Double length)
{
if (lineString == null || lineString.IsEmpty)
throw new System.ArgumentException("Linestring is null or Empty", "lineString");
//var gf = new NetTopologySuite.Geometries.GeometryFactory();
//var ntsLine = (NetTopologySuite.Geometries.LineString)
// SharpMap.Converters.NTS.GeometryConverter.ToNTSGeometry(lineString, gf);
var ret = new System.Collections.Generic.List<GeoAPI.Geometries.ILineString>();
var lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(lineString);
double currentLength = 0d;
while (currentLength < lineString.Length)
{
var tmpLine = (GeoAPI.Geometries.ILineString)
lil.ExtractLine(currentLength, currentLength + length);
ret.Add(tmpLine);
currentLength += length;
}
return lineString.Factory.CreateMultiLineString(ret.ToArray());
}
private static BaseLabel CreatePathLabel(ILineString line, string text, SizeF textMeasure,
int priority, LabelStyle style, MapViewport map)
{
if (line == null)
{
return(null);
}
var factory = line.Factory;
// Simplify the line for smoother labeling
double avgCharacterSpace = 2d * textMeasure.Width / text.Length * map.PixelWidth;
var simplifier = new NetTopologySuite.Simplify.VWLineSimplifier(line.Coordinates, avgCharacterSpace);
line = factory.CreateLineString(simplifier.Simplify());
var labelLength = textMeasure.Width * map.PixelWidth;
var labelHeight = textMeasure.Height * map.PixelHeight;
var offsetX = style.Offset.X * map.PixelWidth; // positive = increasing measure
var offsetY = style.Offset.Y * map.PixelHeight; // positive = right side of line
var start = 0d;
if (style.HorizontalAlignment == LabelStyle.HorizontalAlignmentEnum.Center)
{
start = line.Length * 0.5 - labelLength * 0.5;
}
else if (style.HorizontalAlignment == LabelStyle.HorizontalAlignmentEnum.Right)
{
start = line.Length - labelLength;
}
start += offsetX;
// Constrain label length
if (labelLength > 0.95 * line.Length && !style.IgnoreLength ||
start + labelLength < 0 || start > line.Length)
{
return(null);
}
// LengthIndexedLine idea courtesy FObermaier
NetTopologySuite.LinearReferencing.LengthIndexedLine lil;
// optimize for detailed lines (eg labelling rivers at continental level)
// ratio and NumPoints based on instinct.... feel free to revise
var mid = start + labelLength / 2.0;
if (labelLength / line.Length < 0.5 && line.NumPoints > 200 && mid >= 0 && mid < line.Length)
{
lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(line);
var midPt = lil.ExtractPoint(mid);
// extract slightly more than label length to ensure offsetCurve follows line geometry
var halfLen = labelLength * 0.6;
// ensure non-negative indexes constrained to line length (due to special LengthIndexLine functionality)
line = (LineString)lil.ExtractLine(Math.Max(0, mid - halfLen), Math.Min(mid + halfLen, line.Length));
// reset start
lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(line);
mid = lil.IndexOf(midPt);
start = mid - labelLength / 2.0;
}
// basic extend
var end = start + labelLength;
if (start < 0 || end > line.Length)
{
line = ExtendLine(line,
start <0 ? -1 * start : 0,
end> line.Length ? end - line.Length : 0);
start = 0;
end = start + labelLength;
}
lil = new NetTopologySuite.LinearReferencing.LengthIndexedLine(line);
// reverse
var startPt = lil.ExtractPoint(start);
var endPt = lil.ExtractPoint(end);
if (LineNeedsReversing(startPt, endPt, false, map))
{
start = end;
end = start - labelLength;
}
line = (ILineString)lil.ExtractLine(start, end);
// Build offset curve
ILineString offsetCurve;
var bufferParameters =
new NetTopologySuite.Operation.Buffer.BufferParameters(4,
GeoAPI.Operation.Buffer.EndCapStyle.Flat);
// determine offset curve that will run through the vertical centre of the text
if (style.VerticalAlignment != LabelStyle.VerticalAlignmentEnum.Middle)
{
var ocb = new NetTopologySuite.Operation.Buffer.OffsetCurveBuilder(factory.PrecisionModel,
bufferParameters);
// Left side positive
var offsetCurvePoints = ocb.GetOffsetCurve(line.Coordinates,
((int)style.VerticalAlignment - 1) * 0.5 * labelHeight - offsetY);
offsetCurve = factory.CreateLineString(offsetCurvePoints);
}
else
{
offsetCurve = line;
}
// basic extend
var ratio = labelLength / offsetCurve.Length;
if (ratio > 1.01)
{
var diff = labelLength - offsetCurve.Length;
offsetCurve = ExtendLine(offsetCurve, diff / 2d, diff / 2d);
}
// enclosing polygon in world coords
var affectedArea = (IPolygon)offsetCurve.Buffer(0.5d * labelHeight, bufferParameters);
// fast, basic check (technically should use polygons for rotated views)
if (!map.Envelope.Contains(affectedArea.EnvelopeInternal))
{
return(null);
}
// using labelBox to pass text height to WarpedPath
return(new PathLabel(text, LineStringToPath(offsetCurve, map), 0, priority,
new LabelBox(0, 0, textMeasure.Width, textMeasure.Height), style)
{
AffectedArea = affectedArea
});
}
private void RenderLineLabel(TextSymbolizer textSymbolizer, Feature feature)
{
//TODO labels could be not strings
var str = feature.Attributes.Exists(textSymbolizer.LabelAttribute) ? feature.Attributes[textSymbolizer.LabelAttribute] as string : null;
if (string.IsNullOrWhiteSpace(str))
{
return;
}
var emSize = Graphics.DpiY * textSymbolizer.FontSize / 72;
//ref http://msdn.microsoft.com/en-us/library/xwf9s90b(v=vs.110).aspx
var font = FontCache[textSymbolizer];
var ascent = emSize * font.FontFamily.GetCellAscent(FontStyle.Bold) / font.FontFamily.GetEmHeight(FontStyle.Bold);
Graphics.SmoothingMode = SmoothingMode.HighQuality;
var size = Graphics.MeasureString(str, font);
float spacing = textSymbolizer.Spacing;
var coords = ProjectToCoordinate(feature.Geometry.Coordinates);
var coordsAsLine = new LineString(coords);
var lengthIndexed = new NetTopologySuite.LinearReferencing.LengthIndexedLine(coordsAsLine);
var labelCount = (int)((coordsAsLine.Length - spacing) / (size.Width + spacing));
if (labelCount < 1 || textSymbolizer.Spacing == 0)
{
labelCount = 1;
}
//work out spacing based on the amount of labels we'll be putting on
spacing = ((float)coordsAsLine.Length / labelCount) - size.Width;
for (var i = 0; i < labelCount; i++)
{
var labelCenterLength = (spacing + size.Width) * (0.5f + i);
var subLine = lengthIndexed.ExtractLine(labelCenterLength - (size.Width / 2), labelCenterLength + (size.Width / 2));
if (subLine.Coordinates.Length < 2)
{
continue;
}
var firstCoord = subLine.Coordinates[0];
var lastCoord = subLine.Coordinates[subLine.Coordinates.Length - 1];
var middleOfLabelLinePoint = lengthIndexed.ExtractPoint(labelCenterLength);
var midPoint = new PointF((float)(firstCoord.X + lastCoord.X + middleOfLabelLinePoint.X + middleOfLabelLinePoint.X) * 0.25f, (float)(firstCoord.Y + lastCoord.Y + middleOfLabelLinePoint.Y + middleOfLabelLinePoint.Y) * 0.25f);
var angle = (float)(Math.Atan2(lastCoord.Y - firstCoord.Y, lastCoord.X - firstCoord.X) * 180 / Math.PI);
//Keep the text up the right way
while (angle + Config.Angle > 90)
{
angle -= 180;
}
while (angle + Config.Angle < -90)
{
angle += 180;
}
TryRenderText(textSymbolizer, feature, emSize, str, midPoint, SizeF.Empty, new SizeF(size.Width, ascent), angle);
}
}