package au.gov.amsa.animator;
   
   import java.awt.Color;
   import java.awt.Graphics2D;
   import java.awt.Rectangle;
   import java.awt.RenderingHints;
   import java.awt.geom.AffineTransform;
   import java.awt.geom.Point2D;
   import java.awt.geom.Point2D.Float;
  import java.awt.image.BufferedImage;
  import java.io.File;
  import java.io.IOException;
  
  import javax.imageio.ImageIO;
  
  import org.geotools.geometry.jts.ReferencedEnvelope;
  import org.geotools.map.MapContent;
  import org.geotools.referencing.crs.DefaultGeographicCRS;
  import org.geotools.renderer.lite.RendererUtilities;
  import org.geotools.renderer.lite.StreamingRenderer;
  
  public class ImageDemo {
  
      public static void main(String[] args) throws IOException {
          // Coastlines, country borders and a star on Canberra
          MapContent map = Map.createMap();
  
          // set the view bounds
          double minLon = 90;
          double maxLon = 175;
          double minLat = -50;
          double maxLat = 0;
          ReferencedEnvelope bounds = new ReferencedEnvelope(minLon, maxLon, minLat, maxLat, DefaultGeographicCRS.WGS84);
  
          // just set the width of the output image, the height will be set so that
          // referenced envelope fits exactly in the image bounds
          int width = 800;
          double ratio = (maxLat - minLat) / (maxLon - minLon);
          int proportionalHeight = (int) Math.round(width * ratio);
  
          // create a buffered image
          Rectangle imageBounds = new Rectangle(0, 0, width, proportionalHeight);
          BufferedImage image = createImage(imageBounds);
          Graphics2D gr = image.createGraphics();
          gr.setPaint(Color.WHITE);
          gr.fill(imageBounds);
          
          // paint the MapContent on to the image
          StreamingRenderer renderer = new StreamingRenderer();
          renderer.setMapContent(map);
          renderer.paint(gr, imageBounds, bounds);
          
          // the transform converts lat, long to image coordinates
          AffineTransform worldToScreen = RendererUtilities.worldToScreenTransform(bounds,
                  new Rectangle(0, 0, image.getWidth(), image.getHeight()));
  
          // Draw the string Canberra
          Float p = toScreen(worldToScreen, -35.2809, 149.1300);
          gr.setColor(Color.blue);
          gr.drawString("Canberra", p.x + 5, p.y);
          
          // output the buffered image to a file
          ImageIO.write(image, "png", new File("target/image.png"));
      }
  
      private static BufferedImage createImage(Rectangle imageBounds) {
          BufferedImage img = new BufferedImage(imageBounds.width, imageBounds.height, BufferedImage.TYPE_INT_RGB);
          Graphics2D g = img.createGraphics();
          g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
          g.setBackground(Color.white);
          return img;
      }
  
      private static Point2D.Float toScreen(AffineTransform worldToScreen, double lat, double lon) {
          Point2D.Float a = new Point2D.Float((float) lon, (float) lat);
          Point2D.Float b = new Point2D.Float();
          worldToScreen.transform(a, b);
          return b;
      }
  
  }