0

I am trying to Print map where the layer in the web application is a RasterLayer

The slider in the web app mask's the RasterLayer.

I am using ArcGIS JS API 3.33

Following is the code smaple

NOTE: To run the sample you would need to update the printing service URL at line number 127

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no">
<title>Raster Layer with Pixel Filter</title>

<link rel="stylesheet" href="https://js.arcgis.com/3.33/dijit/themes/claro/claro.css">
<link rel="stylesheet" href="https://js.arcgis.com/3.33/esri/css/esri.css">

<style>
html, body, #map
{
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
}
#status
{
  background-color: #000;
  color: #FFF;
  border: solid 1px #FFF;
  -moz-border-radius: 5px;
  -webkit-border-radius: 5px;
  border-radius: 5px;
  padding: 3px;
  position: absolute;
  right: 10px;
  bottom: 10px;
  z-index: 99;
}
.shadow
{
  -moz-border-radius: 6px;
  -webkit-border-radius: 6px;
  border-radius: 6px;
  background-color: #FFF;
  padding: 8px;
}
#footer
{
  height: 90px;
  width: 50%;
  margin: 0 auto;
  padding: 15px;
  position: absolute;
  bottom: 20px;
  left: 20px;
  z-index: 30;
}

      /* make all dijit buttons the same width */
      .dijitButton .dijitButtonNode, #drawingWrapper, #printButton {
        width: 160px;
      }
</style>

<script type="text/javascript" src="https://js.arcgis.com/3.33/"></script>
<script>
 require([
        "esri/map",
        
        "esri/domUtils",
        // "dojo/parser",
        // "dojo/dom",
        // "dojo/dom-construct",
        "dojo/on",
        "dijit/registry",
        "esri/layers/RasterLayer",
        "esri/geometry/Extent",
        "esri/SpatialReference",
        "dijit/form/HorizontalSlider",
        "dojox/form/RangeSlider",
        "dijit/form/HorizontalRule",
        "dijit/form/HorizontalRuleLabels",
        "esri/layers/ImageServiceParameters",
        "esri/layers/MosaicRule",
        "esri/layers/RasterFunction",
        "esri/layers/DimensionalDefinition",

         "esri/toolbars/draw", "esri/dijit/Print",
        "esri/layers/ArcGISTiledMapServiceLayer", "esri/layers/ArcGISDynamicMapServiceLayer",
        "esri/layers/LayerDrawingOptions",
        "esri/symbols/SimpleMarkerSymbol", "esri/symbols/SimpleLineSymbol", 
        "esri/symbols/SimpleFillSymbol", "esri/graphic",
        "esri/renderers/ClassBreaksRenderer",
        "esri/config",
        "dojo/_base/array", "esri/Color", "dojo/parser", 
        "dojo/query", "dojo/dom", "dojo/dom-construct", 
        "dijit/form/CheckBox", "dijit/form/Button",

        "dijit/layout/BorderContainer", "dijit/layout/ContentPane", "dojo/domReady!"
      ], function(
        Map, 

         domUtils, on, registry, RasterLayer, Extent,
    SpatialReference, HorizontalSlider, RangeSlider, HorizontalRule, HorizontalRuleLabels,
    ImageServiceParameters, MosaicRule, RasterFunction, DimensionalDefinition,

        Draw, Print,
        ArcGISTiledMapServiceLayer, ArcGISDynamicMapServiceLayer,
        LayerDrawingOptions,
        SimpleMarkerSymbol, SimpleLineSymbol,
        SimpleFillSymbol, Graphic,
        ClassBreaksRenderer,
        esriConfig,
        arrayUtils, Color, parser, 
        query, dom, domConstruct, 
        CheckBox, Button
      ) {
  parser.parse();
  var currentMin, currentMax;
  var rasterUrl = "https://sampleserver6.arcgisonline.com/arcgis/rest/services/ScientificData/SeaTemperature/ImageServer";

  //set up slider
  var slider = registry.byId("pixelSlider");

  var initExtent = new Extent(-130, -68, 150, 68, new SpatialReference(4326));
  var map = new Map("map", {
    extent: initExtent,
    basemap: "gray"
  });

   var printer = new Print({
    map: map,
    url: "UPDATE_YOUR_PRINTING_SERVICE_URL"
  }, dom.byId("printButton"));
  printer.startup();


  var sliderMin = -3;  //min sea surface temp of -3 deg C
  var sliderMax = 37;  //max sea surface temp of 37 deg C
  slider.minimum = sliderMin;
  slider.maximum = sliderMax;
  slider.value = [sliderMin, sliderMax];

  // hook up slider events
  slider.on("mouseup", setPixelFilter);
  slider.on("change", setPixelFilter);

  //set up slider labels
  var sliderLabels = new HorizontalRuleLabels({
    container: "bottomDecoration",
    labels: [sliderMin.toFixed(0).toString(), sliderMax.toFixed(0).toString()]
  }, domConstruct.create("div", {}, dom.byId("pixelLabels")));

  //set up blue to red color ramp inside array
  var colorRamp = [];
  for (var i = 0; i < 256; i++) {
    colorRamp.push( [i, 30, 255 - i] );
  }

  /***************************************************************
  * This image service has multiple dimensions including depth and time.
  * If you are only interested in viewing temperatures at a specific time
  * and at a specific depth, use dimensional definisions
  **************************************************************/

  var dim = [];   //define dimensional definition as array
  //DEPTH: show only temperatures at sea surface
  dim.push(new DimensionalDefinition({
    variableName: "water_temp",
    dimensionName: "StdZ",  //water depth
    values: [0],  //sea surface or 0ft
    isSlice: true
  }));
  //TIME: only show temperatures for the week of April 7, 2014
  dim.push(new DimensionalDefinition({
    "variableName": "water_temp",
    "dimensionName": "StdTime", //time temp was recorded
    "values": [1396828800000], //Week of April 7, 2014
    "isSlice": true
  }));

  var defaultMosaic = {};
  defaultMosaic.multidimensionalDefinition = dim;
  var params = new ImageServiceParameters();
  params.mosaicRule = new MosaicRule(defaultMosaic);

  //the service has a default "Stretched" function and a "None" function, we want original data "None"
  var rf = new RasterFunction();
  rf.functionName = "None";
  params.renderingRule = rf;

  //Define the raster layer and add to map
  var rasterLayer = new RasterLayer(rasterUrl, {
    opacity: 1,
    pixelFilter: maskPixels,
    imageServiceParameters: params
  });
  map.addLayer(rasterLayer);

  rasterLayer.on("update-start", function () {
    domUtils.show(dom.byId("status"));
  });
  rasterLayer.on("update-end", function () {
    domUtils.hide(dom.byId("status"));
  });

  // The pixel filter
  function maskPixels(pixelData) {
    if (pixelData == null || pixelData.pixelBlock == null) {
      return;
    }
    if (currentMin === undefined || currentMax === undefined) {
      setPixelFilter();
    }
    var pixelBlock = pixelData.pixelBlock;
    var pixels = pixelBlock.pixels;
    var mask = pixelBlock.mask;
    var numPixels = pixelBlock.width * pixelBlock.height;
    var minVal = rasterLayer.bands[0].min;
    var maxVal = rasterLayer.bands[0].max;
    var factor = 255.0 / (maxVal - minVal);
    if (pixels == null) {
      return;
    }
    var p1 = pixels[0];
    var pr = new Uint8Array(p1.length); //set up array for red values
    var pg = new Uint8Array(p1.length); //set up array for green values
    var pb = new Uint8Array(p1.length); //set up array for blue values

    if (mask == null) {
      mask = new Uint8Array(p1.length);   //mask = new Uint8Array(p1.length);
      pixelBlock.mask = mask;
    }
    var p = [];
    //if pixel value lies between slider min and max, display it (set value to 1)
    //if not, don't display it (set the value to 0)
    for (var i = 0; i < numPixels; i++) {
      mask[i] = (p1[i] >= Math.floor(currentMin) && p1[i] <= Math.floor(currentMax)) ? 1 : 0;

      //apply color based on temperature value of each pixel
      if (mask[i]) {
        p[i] = Math.floor((p1[i] - minVal) * factor);
        pr[i] = colorRamp[p[i]][0];  //red
        pg[i] = colorRamp[p[i]][1];  //green
        pb[i] = colorRamp[p[i]][2];  //blue
      }
    }

    pixelData.pixelBlock.pixels = [pr, pg, pb];  //assign rgb values to each pixel
    pixelData.pixelBlock.statistics = null;
    pixelData.pixelBlock.pixelType = "U8";
  }

  //Redraw raster layer and dynamically change text on slider move
  function setPixelFilter() {
    var val = slider.get("value");
    currentMin = Math.floor(val[0]);
    currentMax = Math.floor(val[1]);
    if (val) {
      dom.byId("pixelVal").innerHTML = "Currently displaying locations with sea temperatures from " + currentMin + "°C to " + currentMax + "°C";
    }
    else {
      dom.byId("pixelVal").innerHTML = "Currently displaying all temperatures.";
    }
    rasterLayer.redraw();
  }
});
</script>
</head>

<body class="claro">
  <div id="map" >
     <div id="printButton"></div>
    <div id="status">
        Loading...
    </div>
    <div id="footer" class="shadow">
      <span style='font-weight: 600; font-size: 130%;' id='elevSpan'>Sea Surface Temperature (°C) on April 7, 2014</span><br><br>
      <div id='pixelVal'></div>
      <div id="pixelSlider" data-dojo-type="dojox/form/HorizontalRangeSlider" data-dojo-props="showButtons:'false', intermediateChanges:'false', slideDuration:'0'">
        <div data-dojo-type="dijit/form/HorizontalRule"></div>
        <div id="pixelLabels"></div>
      </div>
    </div>
  </div>
</body>

</html>

Following is how the app looks like: enter image description here

The printing result looks like following: enter image description here

Notice the threshold applied for masking values in the web application are not acknowledged by the print service.

2

This is a known limitation of the print service. If a Raster or Imagery layer has a pixel filter, the updated values will not be acknowledged by the print service.

In ArcGIS API for JavaScript 4.x, we have a workaround where you can use a view.takeScreenshot() method: https://developers.arcgis.com/javascript/latest/sample-code/sceneview-screenshot/index.html

There is no workaround for ArcGIS API for JavaScript 3.x.

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.