public static Canvas RenderLabelLayer(IViewport viewport, LabelLayer layer)
{
var canvas = new Canvas { Opacity = layer.Opacity };
// todo: take into account the priority
var features = layer.GetFeaturesInView(viewport.Extent, viewport.Resolution).ToList();
var layerStyles = BaseLayer.GetLayerStyles(layer);
foreach (var layerStyle in layerStyles)
{
foreach (var feature in features)
{
var style = (layerStyle is IThemeStyle) ? (layerStyle as IThemeStyle).GetStyle(feature) : layerStyle;
if ((style == null) ||
(style.Enabled == false) ||
(style.MinVisible > viewport.Resolution) ||
(style.MaxVisible < viewport.Resolution)) continue;
if (!(style is LabelStyle)) throw new Exception("Style of label is not a LabelStyle");
var labelStyle = style as LabelStyle;
labelStyle.Text = layer.GetLabelText(feature);
var postion = feature.Geometry.GetBoundingBox().GetCentroid();
var labelText = labelStyle.GetLabelText(feature);
canvas.Children.Add(SingleLabelRenderer.RenderLabel(postion, labelStyle, viewport, labelText));
}
}
return canvas;
}
private static ILayer CreateCityLabelLayer(IProvider citiesProvider)
{
var cityLabelLayer = new LabelLayer("City labels");
cityLabelLayer.DataSource = citiesProvider;
cityLabelLayer.DataSource.SRID = 3785;
cityLabelLayer.Enabled = true;
cityLabelLayer.LabelColumn = "NAME";
cityLabelLayer.Styles.Add(CreateCityLabelTheme());
cityLabelLayer.LabelFilter = LabelCollisionDetection.ThoroughCollisionDetection;
return cityLabelLayer;
}
private static LabelLayer CreateCountryLabelLayer(IProvider countryProvider)
{
var countryLabelLayer = new LabelLayer("Country labels");
countryLabelLayer.DataSource = countryProvider;
countryLabelLayer.DataSource.SRID = 3785;
countryLabelLayer.Enabled = true;
countryLabelLayer.LabelColumn = "NAME";
countryLabelLayer.MaxVisible = double.MaxValue;
countryLabelLayer.MinVisible = double.MinValue;
countryLabelLayer.MultipartGeometryBehaviour = LabelLayer.MultipartGeometryBehaviourEnum.Largest;
countryLabelLayer.Styles.Add(CreateCountryLabelTheme());
return countryLabelLayer;
}
public static Canvas RenderStackedLabelLayer(IViewport viewport, LabelLayer layer)
{
var canvas = new Canvas();
canvas.Opacity = layer.Opacity;
//todo: take into account the priority
var features = layer.GetFeaturesInView(viewport.Extent, viewport.Resolution);
var margin = viewport.Resolution * 50;
foreach (var layerStyle in layer.Styles)
{
var style = layerStyle;
var clusters = new List<Cluster>();
//todo: repeat until there are no more merges
ClusterFeatures(clusters, features, margin, layerStyle, viewport.Resolution);
foreach (var cluster in clusters)
{
Offset stackOffset = null;
foreach (var feature in cluster.Features.OrderBy(f => f.Geometry.GetBoundingBox().GetCentroid().Y))
{
if (layerStyle is IThemeStyle) style = (layerStyle as IThemeStyle).GetStyle(feature);
if ((style == null) || (style.Enabled == false) || (style.MinVisible > viewport.Resolution) || (style.MaxVisible < viewport.Resolution)) continue;
if (stackOffset == null) //first time
{
stackOffset = new Offset();
if (cluster.Features.Count > 1)
canvas.Children.Add(RenderBox(cluster.Box, viewport));
}
else stackOffset.Y += 18; //todo: get size from text, (or just pass stack nr)
if (!(style is LabelStyle)) throw new Exception("Style of label is not a LabelStyle");
var labelStyle = style as LabelStyle;
string labelText = layer.GetLabel(feature);
var position = new Mapsui.Geometries.Point(cluster.Box.GetCentroid().X, cluster.Box.Bottom);
canvas.Children.Add(RenderLabel(position, stackOffset, labelStyle, viewport, labelText));
}
}
}
return canvas;
}
public static Canvas Render(IViewport viewport, LabelLayer layer)
{
// todo: Move stack functionality to Mapsui core.
// step 1) Split RenderStackedLabelLayer into a method
// GetFeaturesInViewStacked en a RenderStackedLabel
// which can later be replace by normal label rendering.
// The method GetFeaturesInViewStacked
// returns a style with an offset determined by the stackoffset
// and a position determined by CenterX en Cluster.Box.Bottom.
// step 2) Move GetFeaturesInViewStacked to a GetFeaturesInView
// method of a new StackedLabelLayed.
var canvas = new Canvas { Opacity = layer.Opacity };
// todo: take into account the priority
var features = layer.GetFeaturesInView(viewport.Extent, viewport.Resolution).ToArray();
var margin = viewport.Resolution * 50;
const int symbolSize = 32; // todo: determine margin by symbol size
const int boxMargin = symbolSize / 2;
var clusters = new List<Cluster>();
//todo: repeat until there are no more merges
ClusterFeatures(clusters, features, margin, layer.Style, viewport.Resolution);
const int textHeight = 18;
foreach (var cluster in clusters)
{
var stackOffsetY = double.NaN;
var orderedFeatures = cluster.Features.OrderBy(f => f.Geometry.GetBoundingBox().GetCentroid().Y);
if (cluster.Features.Count > 1) canvas.Children.Add(RenderBox(cluster.Box, viewport));
foreach (var feature in orderedFeatures)
{
if (double.IsNaN(stackOffsetY)) // first time
stackOffsetY = textHeight * 0.5 + boxMargin;
else
stackOffsetY += textHeight; //todo: get size from text (or just pass stack nr)
LabelStyle style;
if (layer.Style is IThemeStyle)
{
style = (LabelStyle)((IThemeStyle)layer.Style).GetStyle(feature);
}
else
{
style = (LabelStyle)layer.Style;
}
var labelStyle = new LabelStyle(style)
{
Text = layer.GetLabelText(feature) //we only use the layer for the text, this should be returned by style
};
labelStyle.Offset.Y += stackOffsetY;
// since the box can be rotated, find the minimal Y value of all 4 corners
var rotatedBox = cluster.Box.Rotate(-viewport.Rotation);
var minY = rotatedBox.Vertices.Select(v => v.Y).Min();
var position = new Geometries.Point(cluster.Box.GetCentroid().X, minY);
var labelText = labelStyle.GetLabelText(feature);
canvas.Children.Add(SingleLabelRenderer.RenderLabel(position, labelStyle, viewport, labelText));
}
}
return canvas;
}
public static Map InitializeMap()
{
//Initialize a new map based on the simple map
var map = new Map();
//Layer osm = new Layer("OSM");
//string url = "http://labs.metacarta.com/wms-c/tilecache.py?version=1.1.1&request=GetCapabilities&service=wms-c";
//var tileSources = TileSourceWmsC.TileSourceBuilder(new Uri(url), null);
//var tileSource = new List<ITileSource>(tileSources).Find(source => source.Schema.Name == "osm-map");
//osm.DataSource = new TileProvider(tileSource, "OSM");
//map.Layers.Add(osm);
//Set up countries layer
var countryLayer = new Layer("Countries");
//Set the datasource to a shapefile in the App_data folder
countryLayer.DataSource = new ShapeFile("GeoData/World/countries.shp", true);
countryLayer.DataSource.SRID = 4326;
var style = new VectorStyle
{
Fill = new Brush { Color = Color.Green },
Outline = new Pen { Color = Color.Black }
};
countryLayer.Styles.Add(style);
map.Layers.Add(countryLayer);
//set up cities layer
var cityLayer = new Layer("Cities");
//Set the datasource to a shapefile in the App_data folder
cityLayer.DataSource = new ShapeFile("GeoData/World/cities.shp", true);
cityLayer.DataSource.SRID = 4326;
cityLayer.MaxVisible = 0.09;
map.Layers.Add(cityLayer);
//Set up a country label layer
var countryLabelLayer = new LabelLayer("Country labels");
countryLabelLayer.DataSource = countryLayer.DataSource;
countryLabelLayer.DataSource.SRID = 4326;
countryLabelLayer.Enabled = true;
countryLabelLayer.MaxVisible = 0.18;
countryLabelLayer.MinVisible = 0.054;
countryLabelLayer.LabelColumn = "NAME";
var labelStyle = new LabelStyle();
labelStyle.ForeColor = Color.Black;
labelStyle.Font = new Font { FontFamily = "GenericSerif", Size = 12 };
labelStyle.BackColor = new Brush { Color = new Color { A = 128, R = 255, G = 255, B = 255 } };
labelStyle.HorizontalAlignment = LabelStyle.HorizontalAlignmentEnum.Center;
countryLabelLayer.MultipartGeometryBehaviour = LabelLayer.MultipartGeometryBehaviourEnum.Largest;
countryLabelLayer.Styles.Add(labelStyle);
map.Layers.Add(countryLabelLayer);
//Set up a city label layer
var cityLabelLayer = new LabelLayer("City labels");
cityLabelLayer.DataSource = cityLayer.DataSource;
cityLabelLayer.DataSource.SRID = 4326;
cityLabelLayer.Enabled = true;
cityLabelLayer.LabelColumn = "NAME";
cityLabelLayer.MaxVisible = countryLabelLayer.MinVisible;
cityLabelLayer.MinVisible = 0;
cityLabelLayer.LabelFilter = LabelCollisionDetection.ThoroughCollisionDetection;
var cityLabelStyle = new LabelStyle();
cityLabelStyle.ForeColor = Color.Black;
cityLabelStyle.Font = new Font { FontFamily = "GenericSerif", Size = 11 };
cityLabelStyle.HorizontalAlignment = LabelStyle.HorizontalAlignmentEnum.Left;
cityLabelStyle.VerticalAlignment = LabelStyle.VerticalAlignmentEnum.Bottom;
cityLabelStyle.Offset = new Offset { X = 3, Y = 3 };
cityLabelStyle.Halo = new Pen { Color = Color.Yellow, Width = 2 };
cityLabelStyle.CollisionDetection = true;
cityLabelLayer.Styles.Add(cityLabelStyle);
map.Layers.Add(cityLabelLayer);
//Set a gradient theme on the countries layer, based on Population density
//First create two styles that specify min and max styles
//In this case we will just use the default values and override the fill-colors
//using a colorblender. If different line-widths, line- and fill-colors where used
//in the min and max styles, these would automatically get linearly interpolated.
IStyle min = new Style();
IStyle max = new Style();
//Create theme using a density from 0 (min) to 400 (max)
var popdens = new GradientTheme("PopDens", 0, 400, min, max);
//We can make more advanced coloring using the ColorBlend'er.
//Setting the FillColorBlend will override any fill-style in the min and max fills.
//In this case we just use the predefined Rainbow colorscale
popdens.FillColorBlend = ColorBlend.Rainbow5;
countryLayer.Styles.Add(popdens);
//Lets scale the labels so that big countries have larger texts as well
var lblMin = new LabelStyle();
var lblMax = new LabelStyle();
lblMin.ForeColor = Color.Black;
lblMin.Font = new Font { FontFamily = "Sans Serif", Size = 6 };
lblMax.ForeColor = Color.Black;
lblMax.BackColor = new Brush { Color = new Color { A = 128, R = 255, G = 255, B = 255 } };
lblMin.BackColor = lblMax.BackColor;
lblMax.Font = new Font { FontFamily = "Sans Serif", Size = 9 };
countryLabelLayer.Styles.Add(new GradientTheme("PopDens", 0, 400, lblMin, lblMax));
//Lets scale city icons based on city population
//cities below 1.000.000 gets the smallest symbol, and cities with more than 5.000.000 the largest symbol
var citymin = new SymbolStyle();
var citymax = new SymbolStyle();
const string iconPath = "Images/icon.png";
if (!File.Exists(iconPath))
{
throw new Exception(
String.Format("Error file '{0}' could not be found, make sure it is at the expected location",
iconPath));
}
citymin.Symbol = new Bitmap { Data = new FileStream(iconPath, FileMode.Open, FileAccess.Read) };
citymin.SymbolScale = 0.5f;
citymax.Symbol = new Bitmap { Data = new FileStream(iconPath, FileMode.Open, FileAccess.Read) };
citymax.SymbolScale = 1f;
cityLayer.Styles.Add(new GradientTheme("Population", 1000000, 5000000, citymin, citymax));
var geodanLayer = new Layer("Geodan");
geodanLayer.DataSource = new MemoryProvider(new Point(4.9130567, 52.3422033));
geodanLayer.Styles.Add(new SymbolStyle { Symbol = new Bitmap { Data = new FileStream(iconPath, FileMode.Open, FileAccess.Read) } });
map.Layers.Add(geodanLayer);
//limit the zoom to 360 degrees width
map.BackColor = Color.White;
return map;
}
public static Canvas Render(IViewport viewport, LabelLayer layer)
{
throw new NotImplementedException();
}
public static void Render(Graphics graphics, IViewport viewport, LabelLayer labelLayer)
{
var layerStyles = BaseLayer.GetLayerStyles(labelLayer);
foreach (var layerStyle in layerStyles)
{
if (layerStyle.Enabled && labelLayer.MaxVisible >= viewport.Resolution && labelLayer.MinVisible < viewport.Resolution)
{
if (labelLayer.DataSource == null)
throw (new ApplicationException("DataSource property not set"));
graphics.SmoothingMode = SmoothingMode.AntiAlias;
var features = labelLayer.GetFeaturesInView(viewport.Extent, viewport.Resolution);
//Initialize label collection
var labels = new List<Label>();
var style = layerStyle as LabelStyle;
//List<System.Drawing.Rectangle> LabelBoxes; //Used for collision detection
//Render labels
foreach (IFeature feature in features)
{
if (layerStyle is IThemeStyle) style = (layerStyle as IThemeStyle).GetStyle(feature) as LabelStyle;
float rotation = 0;
if (!String.IsNullOrEmpty(labelLayer.RotationColumn))
rotation = float.Parse(feature[labelLayer.RotationColumn].ToString(), NumberStyles.Any, CultureInfo.InvariantCulture);
int priority = labelLayer.Priority;
if (labelLayer.PriorityDelegate != null)
priority = labelLayer.PriorityDelegate(feature);
else if (!String.IsNullOrEmpty(labelLayer.PriorityColumn))
priority = int.Parse(feature[labelLayer.PriorityColumn].ToString(), NumberStyles.Any, CultureInfo.InvariantCulture);
string text;
if (labelLayer.LabelStringDelegate != null)
{
text = labelLayer.LabelStringDelegate(feature);
}
else
{
text = feature[labelLayer.LabelColumn].ToString();
}
if (!string.IsNullOrEmpty(text))
{
if (feature.Geometry is GeometryCollection)
{
var geometryCollection = feature.Geometry as GeometryCollection;
if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.All)
{
foreach (var geometry in geometryCollection)
{
var label = CreateLabel(geometry, text, rotation, priority, style, viewport, graphics);
if (label != null) labels.Add(label);
}
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.CommonCenter)
{
var label = CreateLabel(feature.Geometry, text, rotation, priority, style, viewport, graphics);
if (label != null) labels.Add(label);
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.First)
{
if ((feature.Geometry as GeometryCollection).Collection.Count > 0)
{
Label label = CreateLabel(geometryCollection.Collection[0], text, rotation, 0,
style, viewport, graphics);
if (label != null) labels.Add(label);
}
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.Largest)
{
var coll = (feature.Geometry as GeometryCollection);
if (coll.NumGeometries > 0)
{
double largestVal = 0;
int idxOfLargest = 0;
for (var j = 0; j < coll.NumGeometries; j++)
{
Geometry geom = coll.Geometry(j);
if (geom is LineString && ((LineString)geom).Length > largestVal)
{
largestVal = ((LineString)geom).Length;
idxOfLargest = j;
}
if (geom is MultiLineString && ((MultiLineString)geom).Length > largestVal)
{
largestVal = ((MultiLineString)geom).Length;
idxOfLargest = j;
}
if (geom is Polygon && ((Polygon)geom).Area > largestVal)
{
largestVal = ((Polygon)geom).Area;
idxOfLargest = j;
}
if (geom is MultiPolygon && ((MultiPolygon)geom).Area > largestVal)
{
largestVal = ((MultiPolygon)geom).Area;
idxOfLargest = j;
}
}
var label = CreateLabel(coll.Geometry(idxOfLargest), text, rotation, priority, style,
viewport, graphics);
if (label != null) labels.Add(label);
}
}
}
else
{
var label = CreateLabel(feature.Geometry, text, rotation, priority, style, viewport, graphics);
if (label != null) labels.Add(label);
}
}
}
if (labels.Count > 0) //We have labels to render...
{
if ((layerStyle is LabelStyle) && (layerStyle as LabelStyle).CollisionDetection && labelLayer.LabelFilter != null)
labelLayer.LabelFilter(labels);
foreach (Label label in labels)
{
if (!label.Show) continue;
LabelRenderer.DrawLabel(graphics, label.LabelPoint, label.Style.Offset, label.Style.Font,
label.Style.ForeColor, label.Style.BackColor, label.Halo, label.Rotation, label.Text, viewport);
}
}
}
}
}
public static List<IFeature> RenderStackedLabelLayer(IViewport viewport, LabelLayer layer)
{
var renderedFeatures = new List<IFeature> ();
var canvas = new CALayer ();
canvas.Opacity = (float)layer.Opacity;
//todo: take into account the priority
var features = layer.GetFeaturesInView(viewport.Extent, viewport.Resolution);
var margin = viewport.Resolution * 50;
if(layer.Style != null)
{
var clusters = new List<Cluster>();
//todo: repeat until there are no more merges
ClusterFeatures(clusters, features, margin, layer.Style, viewport.Resolution);
foreach (var cluster in clusters)
{
var feature = cluster.Features.OrderBy(f => f.Geometry.GetBoundingBox().GetCentroid().Y).FirstOrDefault();
//SetFeatureOutline (feature, layer.Name, cluster.Features.Count);
//var bb = RenderBox(cluster.Box, viewport);
//Zorg dat dit ALTIJD decimal zelfde ISet als ViewChanged is
//var feature = cluster.Features.FirstOrDefault ();
var styles = feature.Styles ?? Enumerable.Empty<IStyle>();
foreach (var style in styles)
{
if (feature.Styles != null && style.Enabled)
{
var styleKey = layer.Name; //feature.GetHashCode ().ToString ();
var renderedGeometry = (feature[styleKey] != null) ? (CALayer)feature[styleKey] : null;
var labelText = layer.GetLabelText(feature);
if (renderedGeometry == null) {
//Mapsui.Geometries.Point point, Offset stackOffset, LabelStyle style, IFeature feature, IViewport viewport, string text)
renderedGeometry = RenderLabel(feature.Geometry as Mapsui.Geometries.Point,
style as LabelStyle, feature, viewport, labelText);
feature [styleKey] = renderedGeometry;
feature ["first"] = true;
} else {
feature ["first"] = false;
}
}
}
renderedFeatures.Add (feature);
/*
Offset stackOffset = null;
foreach (var feature in cluster.Features.OrderBy(f => f.Geometry.GetBoundingBox().GetCentroid().Y))
{
if (layerStyle is IThemeStyle) style = (layerStyle as IThemeStyle).GetStyle(feature);
if ((style == null) || (style.Enabled == false) || (style.MinVisible > viewport.Resolution) || (style.MaxVisible < viewport.Resolution)) continue;
if (stackOffset == null) //first time
{
stackOffset = new Offset();
if (cluster.Features.Count > 1)
canvas.AddSublayer (RenderBox(cluster.Box, viewport));
}
else stackOffset.Y += 18; //todo: get size from text, (or just pass stack nr)
if (!(style is LabelStyle)) throw new Exception("Style of label is not a LabelStyle");
var labelStyle = style as LabelStyle;
string labelText = layer.GetLabel(feature);
var position = new Mapsui.Geometries.Point(cluster.Box.GetCentroid().X, cluster.Box.Bottom);
canvas.AddSublayer(RenderLabel(position, stackOffset, labelStyle, feature, viewport, labelText));
}
*/
}
}
return renderedFeatures;
}
public static CALayer RenderLabelLayer(IViewport viewport, LabelLayer layer, List<IFeature> features)
{
var canvas = new CALayer();
canvas.Opacity = (float)layer.Opacity;
//todo: take into account the priority
var stackOffset = new Offset();
if (layer.Style != null)
{
var style = layer.Style;
foreach (var feature in features)
{
if (style is IThemeStyle) style = (style as IThemeStyle).GetStyle(feature);
if ((style == null) || (style.Enabled == false) || (style.MinVisible > viewport.Resolution) || (style.MaxVisible < viewport.Resolution)) continue;
if (!(style is LabelStyle)) throw new Exception("Style of label is not a LabelStyle");
//var labelStyle = style as LabelStyle;
string labelText = layer.GetLabelText(feature);
var label = RenderLabel (feature.Geometry as Mapsui.Geometries.Point,
style as LabelStyle, feature, viewport, labelText);
canvas.AddSublayer(label);
}
}
return canvas;
}
public static void Render(Graphics g, IViewport viewport, LabelLayer labelLayer)
{
foreach (var layerStyle in labelLayer.Styles)
{
if (layerStyle.Enabled && labelLayer.MaxVisible >= viewport.Resolution && labelLayer.MinVisible < viewport.Resolution)
{
if (labelLayer.DataSource == null)
throw (new ApplicationException("DataSource property not set"));
#if !PocketPC
g.SmoothingMode = SmoothingMode.AntiAlias;
#endif
//!!!BoundingBox envelope = map.Envelope; //View to render
//!!!if (CoordinateTransformation != null)
//!!! envelope = GeometryTransform.TransformBox(envelope, CoordinateTransformation.MathTransform.Inverse());
labelLayer.DataSource.Open();
var features = labelLayer.DataSource.GetFeaturesInView(viewport.Extent, viewport.Resolution);
labelLayer.DataSource.Close();
//Initialize label collection
var labels = new List<Label>();
var style = layerStyle as LabelStyle;
//List<System.Drawing.Rectangle> LabelBoxes; //Used for collision detection
//Render labels
foreach (IFeature feature in features)
{
//!!!if (CoordinateTransformation != null)
//!!! features[i].Geometry = GeometryTransform.TransformGeometry(
//!!! features[i].Geometry, CoordinateTransformation. MathTransform);
if (layerStyle is IThemeStyle) style = (layerStyle as ThemeStyle).GetStyle(feature) as LabelStyle;
float rotation = 0;
if (!String.IsNullOrEmpty(labelLayer.RotationColumn))
rotation = float.Parse(feature[labelLayer.RotationColumn].ToString(), NumberStyles.Any, CultureInfo.InvariantCulture);
int priority = labelLayer.Priority;
if (labelLayer.PriorityDelegate != null)
priority = labelLayer.PriorityDelegate(feature);
else if (!String.IsNullOrEmpty(labelLayer.PriorityColumn))
priority = int.Parse(feature[labelLayer.PriorityColumn].ToString(), NumberStyles.Any, CultureInfo.InvariantCulture);
string text;
if (labelLayer.LabelStringDelegate != null)
text = labelLayer.LabelStringDelegate(feature);
else
text = feature[labelLayer.LabelColumn].ToString();
if (text != null && text != String.Empty)
{
if (feature.Geometry is GeometryCollection)
{
if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.All)
{
foreach (Geometry geom in (feature.Geometry as GeometryCollection))
{
Label lbl = CreateLabel(geom, text, rotation, priority, style, viewport, g, labelLayer);
if (lbl != null)
labels.Add(lbl);
}
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.CommonCenter)
{
Label lbl = CreateLabel(feature.Geometry, text, rotation, priority, style, viewport, g, labelLayer);
if (lbl != null)
labels.Add(lbl);
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.First)
{
//!!!
//if ((feature.Geometry as GeometryCollection).Collection.Count > 0)
//{
// Label lbl = CreateLabel((feature.Geometry as GeometryCollection).Collection[0], text,
// rotation, style, map, g, labelTheme);
// if (lbl != null)
// labels.Add(lbl);
//}
}
else if (labelLayer.MultipartGeometryBehaviour == LabelLayer.MultipartGeometryBehaviourEnum.Largest)
{
var coll = (feature.Geometry as GeometryCollection);
if (coll.NumGeometries > 0)
{
double largestVal = 0;
int idxOfLargest = 0;
for (int j = 0; j < coll.NumGeometries; j++)
{
Geometry geom = coll.Geometry(j);
if (geom is LineString && ((LineString)geom).Length > largestVal)
{
largestVal = ((LineString)geom).Length;
idxOfLargest = j;
}
if (geom is MultiLineString && ((MultiLineString)geom).Length > largestVal)
{
largestVal = ((LineString)geom).Length;
idxOfLargest = j;
}
if (geom is Polygon && ((Polygon)geom).Area > largestVal)
{
largestVal = ((Polygon)geom).Area;
idxOfLargest = j;
}
if (geom is MultiPolygon && ((MultiPolygon)geom).Area > largestVal)
{
largestVal = ((MultiPolygon)geom).Area;
idxOfLargest = j;
}
}
Label lbl = CreateLabel(coll.Geometry(idxOfLargest), text, rotation, priority, style,
viewport, g, labelLayer);
if (lbl != null)
labels.Add(lbl);
}
}
}
else
{
Label lbl = CreateLabel(feature.Geometry, text, rotation, priority, style, viewport, g, labelLayer);
if (lbl != null)
labels.Add(lbl);
}
}
}
if (labels.Count > 0) //We have labels to render...
{
if ((layerStyle as LabelStyle).CollisionDetection && labelLayer.LabelFilter != null)
labelLayer.LabelFilter(labels);
for (int i = 0; i < labels.Count; i++)
if (labels[i].Show)
GdiGeometryRenderer.DrawLabel(g, labels[i].LabelPoint, labels[i].Style.Offset,
labels[i].Style.Font, labels[i].Style.ForeColor,
labels[i].Style.BackColor, (layerStyle as LabelStyle).Halo, labels[i].Rotation,
labels[i].Text, viewport);
}
labels = null;
}
}
}
private static Label CreateLabel(IGeometry feature, string text, float rotation, int priority, LabelStyle style, IViewport viewport,
Graphics g, LabelLayer labelTheme)
{
SizeF gdiSize = g.MeasureString(text, style.Font.Convert());
var size = new Mapsui.Styles.Size { Width = gdiSize.Width, Height = gdiSize.Height };
Mapsui.Geometries.Point position = viewport.WorldToScreen(feature.GetBoundingBox().GetCentroid());
position.X = position.X - size.Width * (short)style.HorizontalAlignment * 0.5f;
position.Y = position.Y - size.Height * (short)style.VerticalAlignment * 0.5f;
if (position.X - size.Width > viewport.Width || position.X + size.Width < 0 ||
position.Y - size.Height > viewport.Height || position.Y + size.Height < 0)
return null;
else
{
Label lbl;
if (!style.CollisionDetection)
lbl = new Label(text, position, rotation, priority, null, style);
else
{
//Collision detection is enabled so we need to measure the size of the string
lbl = new Label(text, position, rotation, priority,
new LabelBox(position.X - size.Width * 0.5f - style.CollisionBuffer.Width,
position.Y + size.Height * 0.5f + style.CollisionBuffer.Height,
size.Width + 2f * style.CollisionBuffer.Width,
size.Height + style.CollisionBuffer.Height * 2f), style);
}
if (feature.GetType() == typeof(LineString))
{
var line = feature as LineString;
if (line.Length / viewport.Resolution > size.Width) //Only label feature if it is long enough
CalculateLabelOnLinestring(line, ref lbl, viewport);
else
return null;
}
return lbl;
}
}
private static Label CreateLabel(IGeometry feature, string text, float rotation, LabelStyle style, IViewport viewport, Graphics g, LabelLayer labelTheme)
{
return CreateLabel(feature, text, rotation, labelTheme.Priority, style, viewport, g, labelTheme);
}
