public static void Draw(SKCanvas canvas, LabelStyle style, IFeature feature, float x, float y)
{
var text = style.GetLabelText(feature);
if (string.IsNullOrEmpty(text))
{
return;
}
DrawLabel(canvas, x, y, style, text);
}
public static void Draw(SKCanvas canvas, LabelStyle style, IFeature feature, Point destination,
float layerOpacity)
{
var text = style.GetLabelText(feature);
if (string.IsNullOrEmpty(text))
{
return;
}
DrawLabel(canvas, (float)destination.X, (float)destination.Y, style, text, layerOpacity);
}
private static List <IFeature> GetFeaturesInView(double resolution, LabelStyle labelStyle,
IEnumerable <IFeature>?features, Pen line, Brush?fill)
{
if (features == null)
{
return(new List <IFeature>());
}
var margin = resolution * 50;
var clusters = new List <Cluster>();
// todo: repeat until there are no more merges
ClusterFeatures(clusters, features, margin, labelStyle, resolution);
const int textHeight = 18;
var results = new List <IFeature>();
foreach (var cluster in clusters)
{
if (cluster.Features?.Count > 1)
{
results.Add(CreateBoxFeature(resolution, cluster, line, fill));
}
var offsetY = double.NaN;
var orderedFeatures = cluster.Features?.OrderBy(f => f.Extent.Centroid.Y);
if (orderedFeatures != null)
{
foreach (var pointFeature in orderedFeatures)
{
var position = CalculatePosition(cluster);
offsetY = CalculateOffsetY(offsetY, textHeight);
var labelText = labelStyle.GetLabelText(pointFeature);
var labelFeature = CreateLabelFeature(position, labelStyle, offsetY, labelText);
results.Add(labelFeature);
}
}
}
return(results);
}
public static void DrawAsBitmap(SKCanvas canvas, LabelStyle style, IFeature feature, float x, float y)
{
var text = style.GetLabelText(feature);
var key = text + "_" + style.Font.FontFamily + "_" + style.Font.Size + "_" + (float)style.Font.Size + "_" +
style.BackColor + "_" + style.ForeColor;
if (!LabelBitmapCache.Keys.Contains(key))
{
LabelBitmapCache[key] = new SKBitmapInfo {
Bitmap = CreateLabelAsBitmap(style, text)
}
}
;
var info = LabelBitmapCache[key];
BitmapHelper.RenderTexture(canvas, info.Bitmap, (int)Math.Round(x), (int)Math.Round(y),
offsetX: (float)style.Offset.X, offsetY: (float)-style.Offset.Y,
horizontalAlignment: style.HorizontalAlignment, verticalAlignment: style.VerticalAlignment);
}
public static void DrawAsBitmap(SKCanvas canvas, LabelStyle style, IFeature feature, float x, float y, float layerOpacity)
{
var text = style.GetLabelText(feature);
var key = text + "_" + style.Font.FontFamily + "_" + style.Font.Size + "_" + (float)style.Font.Size + "_" +
style.BackColor + "_" + style.ForeColor;
if (!LabelCache.Keys.Contains(key))
{
LabelCache[key] = new BitmapInfo {
Bitmap = CreateLabelAsBitmap(style, text, layerOpacity)
}
}
;
var info = LabelCache[key];
var offsetX = style.Offset.IsRelative ? info.Width * style.Offset.X : style.Offset.X;
var offsetY = style.Offset.IsRelative ? info.Height * style.Offset.Y : style.Offset.Y;
BitmapRenderer.Draw(canvas, info.Bitmap, (int)Math.Round(x), (int)Math.Round(y),
offsetX: (float)offsetX, offsetY: (float)-offsetY,
horizontalAlignment: style.HorizontalAlignment, verticalAlignment: style.VerticalAlignment);
}
public static void Draw(SKCanvas canvas, LabelStyle style, IFeature feature, float x, float y)
{
var text = style.GetLabelText(feature);
DrawLabel(canvas, x, y, style, text);
}
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 Point(cluster.Box.GetCentroid().X, minY);
var labelText = labelStyle.GetLabelText(feature);
canvas.Children.Add(SingleLabelRenderer.RenderLabel(position, labelStyle, viewport, labelText));
}
}
return(canvas);
}
