Infinite run after adding osm service in a map content and using the paint method of the StreamingRenderer class

Question

When I add osm service in a mapContent

mapContent.addLayer(new AsyncTileLayer(new OSMService("Mapnik", "http://tile.openstreetmap.org/")));

Then when I use the paint method of StreamingRenderer class, there is an infinite run. More precisely the infinite run occurs in the line 563 of the StreamingRenderer class file with :

painterFuture.get();

I call paint method to paint what I add to the mapContent, i.e. here the featureLayer and the osm map.

MapContent mapContent = new MapContent();
mapContent.addLayer(new AsyncTileLayer(new OSMService("Mapnik", "http://tile.openstreetmap.org/")));

CoordinateReferenceSystem crs = CRS.decode("EPSG:4326", true);
ReferencedEnvelope envelope = new ReferencedEnvelope(566516.1128181651, 571832.3519307065, 5275726.889218023, 5281104.067690026, crs);
mapContent.getViewport().setBounds(envelope);

GTRenderer renderer = new StreamingRenderer();
renderer.setMapContent(mapContent);

Rectangle imageBounds;
ReferencedEnvelope mapBounds;
try {
    mapBounds = mapContent.getMaxBounds();
    double heightToWidth = mapBounds.getSpan(1) / mapBounds.getSpan(0);
    imageBounds = new Rectangle(5, 5, 1000, (int) Math.round(1000 * heightToWidth));
} catch (Exception e) {
    throw new RuntimeException(e);
}

BufferedImage mapBufferedImage = new BufferedImage(imageBounds.width, imageBounds.height, BufferedImage.TYPE_INT_ARGB);
Graphics2D gr = mapBufferedImage.createGraphics();
renderer.paint(gr, imageBounds, mapBounds);

Here is the content of the painterFuture object : state = 0, callable = java.util.concurrent.Executors$RunnableAdapter@3533df16[Wrapped task = org.geotools.renderer.lite.StreamingRenderer$PainterThread@15d0849], outcome = null, runner = "Thread[pool-1-thread-1,5,main]", waiters = null

When there is just the featureLayer and not the osm service, the painterFuture object is marked as Completed normally and contains : state = 2, callable = null, outcome = null, runner = null, waiters = null.

With this following code I get an image but that doesn't seems to be the good projection.

ReferencedEnvelope re = layer.getBounds();
mapContent.addLayer(new AsyncTileLayer(new OSMService("Mapnik", "http://tile.openstreetmap.org/")));

CoordinateReferenceSystem source = CRS.decode("EPSG:25832");
CoordinateReferenceSystem target = CRS.decode("EPSG:4326");

MathTransform transform = CRS.findMathTransform(source, target, true);
Envelope targetGeometry = JTS.transform(re, transform);

ReferencedEnvelope envelope = new ReferencedEnvelope(targetGeometry, target);

mapContent.getViewport().setBounds(envelope);

Answer 1

The problem seems to be that you are asking for an area the size of millions of Earths across, so it takes a long time to calculate all the possible (empty) tiles that need to be requested from the OSM server.

CoordinateReferenceSystem crs = CRS.decode("EPSG:4326", true);
ReferencedEnvelope envelope = new ReferencedEnvelope(566516.1128181651, 571832.3519307065, 5275726.889218023, 5281104.067690026, crs);
mapContent.getViewport().setBounds(envelope);

is the problem, those coordinates are clearly not in EPSG:4326 (which is in degrees and runs from -180,180 and -90,90. I suspect you mean EPSG:3857 (Web Mercator).

Fixing that lead to another problem which was that you were exceeding the MaxTileLimit of 128 and also requesting tiles of size 0x0 in the tile layer.

This is because your screen area was 0x0 - so adding the line:

mapContent.getViewport().setScreenArea(imageBounds);

made it run with out error.

Update

Here is the code I used to test.

package spike;

import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;

import org.geotools.data.FileDataStore;
import org.geotools.data.shapefile.ShapefileDataStore;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.map.FeatureLayer;
import org.geotools.map.Layer;
import org.geotools.map.MapContent;
import org.geotools.referencing.CRS;
import org.geotools.renderer.GTRenderer;
import org.geotools.renderer.lite.StreamingRenderer;
import org.geotools.styling.SLD;
import org.geotools.tile.impl.osm.OSMService;
import org.geotools.tile.util.AsyncTileLayer;
import org.geotools.util.URLs;
import org.opengis.referencing.FactoryException;
import org.opengis.referencing.NoSuchAuthorityCodeException;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import org.opengis.referencing.operation.TransformException;

public class OSMLayer {

  public static void main(String[] args)
      throws IOException, NoSuchAuthorityCodeException, TransformException, FactoryException {

    FileDataStore ds = new ShapefileDataStore(URLs.fileToUrl(new File("/home/ian/Data/states/states.shp")));


    Layer featureLayer = new FeatureLayer(ds.getFeatureSource().getFeatures(), SLD.createSimpleStyle(ds.getSchema()));
    MapContent mapContent = new MapContent();
    mapContent.addLayer(new AsyncTileLayer(new OSMService("Mapnik", "http://tile.openstreetmap.org/")));
    mapContent.addLayer(featureLayer);
    CoordinateReferenceSystem crs = CRS.decode("EPSG:3857", true);
    ReferencedEnvelope envelope = new ReferencedEnvelope(566516.1128181651, 571832.3519307065, 5275726.889218023,
        5281104.067690026, crs);
    mapContent.getViewport().setBounds(featureLayer.getBounds().transform(crs, false));

    GTRenderer renderer = new StreamingRenderer();
    renderer.setMapContent(mapContent);

    Rectangle imageBounds;
    ReferencedEnvelope mapBounds;
    try {
      mapBounds = mapContent.getViewport().getBounds();
      double heightToWidth = mapBounds.getSpan(1) / mapBounds.getSpan(0);
      imageBounds = new Rectangle(5, 5, 1000, (int) Math.round(1000 * heightToWidth));
    } catch (Exception e) {
      throw new RuntimeException(e);
    }

    BufferedImage mapBufferedImage = new BufferedImage(imageBounds.width, imageBounds.height,
        BufferedImage.TYPE_INT_ARGB);
    mapContent.getViewport().setScreenArea(imageBounds);
    Graphics2D gr = mapBufferedImage.createGraphics();
    renderer.paint(gr, imageBounds, mapBounds);
    try (FileOutputStream fileOutputStream = new FileOutputStream(new File("out.png"));
        ImageOutputStream outputImageFile = ImageIO.createImageOutputStream(fileOutputStream)) {

      ImageIO.write(mapBufferedImage, "png", outputImageFile);
    } catch (IOException ex) {
      ex.printStackTrace();
    }
  }

}

With my US States layer (mapContent.getViewport().setBounds(featureLayer.getBounds().transform(crs, false)); ) it gives this output:

With your bounding box (mapContent.getViewport().setBounds(envelope);)it gives: