Colormap Renderer

Demonstrates how to use a colormap renderer on raster layer. Colormap renderers can be used to replace values on a raster layer with a color based on the original value brightness.

How it works

To apply a ColormapRenderer to a RasterLayer:

  1. Create a Raster from a raster file.
  2. Create a raster layer from the raster.
  3. Create a List<Integer> representing colors. Colors at the beginning of the list replace the darkest values in the raster and colors at the end of the list replaced the brightest values of the raster.
  4. Create a colormap renderer with the color list and apply it to the raster layer with rasterLayer.setRasterRenderer(colormapRenderer).

Code

/*
 * Copyright 2017 Esri.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.esri.samples.raster.colormap_renderer;

import java.io.File;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

import com.esri.arcgisruntime.layers.RasterLayer;
import com.esri.arcgisruntime.loadable.LoadStatus;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.Basemap;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.raster.ColormapRenderer;
import com.esri.arcgisruntime.raster.Raster;

public class ColormapRendererSample extends Application {

  private MapView mapView;

  @Override
  public void start(Stage stage) {

    try {
      // create stack pane and application scene
      StackPane stackPane = new StackPane();
      Scene scene = new Scene(stackPane);

      // set title, size, and add scene to stage
      stage.setTitle("Colormap Renderer Sample");
      stage.setWidth(800);
      stage.setHeight(700);
      stage.setScene(scene);
      stage.show();

      // create a raster from a local raster file
      Raster raster = new Raster(new File("./samples-data/raster/ShastaBW.tif").getAbsolutePath());

      // create a raster layer
      RasterLayer rasterLayer = new RasterLayer(raster);

      // create a Map with imagery basemap
      ArcGISMap map = new ArcGISMap(Basemap.createImagery());

      // add the map to a map view
      mapView = new MapView();
      mapView.setMap(map);

      // add the raster as an operational layer
      map.getOperationalLayers().add(rasterLayer);

      // create a color map where values 0-150 are red (0xFFFF0000) and 150-250 are yellow (0xFFFFFF00)
      List<Integer> colors = IntStream.range(0, 250)
          .boxed()
          .map(i -> i < 150 ? 0xFFFF0000 : 0xFFFFFF00)
          .collect(Collectors.toList());

      // create a colormap renderer
      ColormapRenderer colormapRenderer = new ColormapRenderer(colors);

      // set the colormap renderer on the raster layer
      rasterLayer.setRasterRenderer(colormapRenderer);

      // set viewpoint on the raster
      rasterLayer.addDoneLoadingListener(() -> {
        if (map.getLoadStatus() == LoadStatus.LOADED) {
          mapView.setViewpointGeometryAsync(rasterLayer.getFullExtent(), 150);
        } else {
          Alert alert = new Alert(Alert.AlertType.ERROR, "Raster Layer Failed to Load!");
          alert.show();
        }
      });

      // add the map view to stack pane
      stackPane.getChildren().addAll(mapView);
    } catch (Exception e) {
      // on any error, display the stack trace.
      e.printStackTrace();
    }
  }

  /**
   * Stops and releases all resources used in application.
   */
  @Override
  public void stop() {

    if (mapView != null) {
      mapView.dispose();
    }
  }

  /**
   * Opens and runs application.
   *
   * @param args arguments passed to this application
   */
  public static void main(String[] args) {

    Application.launch(args);
  }

}


In this topic
  1. How it works
  2. Code