This sample shows how to add an instance of a multidimensional ImageryTileLayer to a Map in a MapView from a portalItem. The ImageryTileLayer in this sample contains the soil moisture and soil temperature information at different altitudes as recorded between 10/22/2015 8:00:00 PM GMT-07:00 and 10/23/2015 11:00:00 AM GMT-07:00. The data was downloaded from NCEP Products Inventory.
How it works
When the application starts, an ImageryTileLayer is initialized with a multidimensionalSubset. The multidimensionalSubset returns only the dimensional slices that meet the criteria. In this case, the soil temperature info will not be available at altitude of 3 meters. This means if user moves the altitude slider thumb to 3 meters while soil temperature information is visible then nothing will be displayed on the map since this information is not available within the layer's multidimensionalSubset.
// Set the multidimensionalSubset on the layer. Limit the
// stdZ dimension from 0 - 1.6m for the soil temperature variable.
// Nothing will be displayed at 3 meters when tsoil@dbll variable info
// is being displayed
const multidimensionalSubset = new MultidimensionalSubset({
subsetDefinitions: [
{
variableName: "soilw@dbll", // soil moisture
dimensionName: "StdTime",
values: [1445569200000, 1445623200000],
isSlice: false
},
{
variableName: "soilw@dbll", // soil moisture
dimensionName: "StdZ",
values: [0, 3],
isSlice: false
},
{
variableName: "tsoil@dbll", // soil temperature
dimensionName: "StdTime",
values: [1445569200000, 1445623200000],
isSlice: false
},
{
variableName: "tsoil@dbll", // soil temperature
dimensionName: "StdZ",
values: [0, 1.6],
isSlice: false
}
]
});
const layer = new ImageryTileLayer({
portalItem: {
id: "b231d6901d474f6584bdb9655ef2be4e"
},
title: "Soil temp, moisture",
multidimensionalSubset
});
Users can choose to display the soil moisture or soil temperature variable in the Map by picking a variable name from the drop down list. This will update the layer's multidimensionalDefinition to display the selected variable. Then, the statistics of the layer's renderer will be updated to match the variable's statistics.
// Change the layer's variable name corresponding the selected variable in the drop down
// variable names in this case represent soil moisture or soil temperature
function changeVariableName(variableName) {
const multidimensionalDefinition = layer.multidimensionalDefinition;
// filter the data by the variable that user selected set the layer's
// multidimensionalDefinition by changing the dimensional definition variable name.
multidimensionalDefinition.forEach((def) => (def.variableName = variableName));
layer.multidimensionalDefinition = multidimensionalDefinition;
// update statistics for the layer's stretch renderer to match
// statistics associated with the chosen variable
// layer.rasterInfo.multidimensionalInfo - returns multidimensional info from the service
const renderer = layer.renderer.clone();
const dimensions = layer.rasterInfo.multidimensionalInfo;
const variable = dimensions.variables.find((variable) => variable.name === variableName);
renderer.statistics = variable.statistics;
layer.renderer = renderer;
}
Users can also visualize how soil moisture or temperature changes at different altitudes by moving the altitude slider thumb, or how it changes over time by playing the TimeSlider widget. The following function runs whenever the altitude slider thumb is moved.
// this function will be called as user adjusts the slider thumb to change the
// altitude slider. Layer's stdZ dimension will be updated on the map to show the soil temp
// or soil moisture at that altitude.
function updateRenderer (dimensionName, sliderData) {
if (!sliderData || !layer.loaded) {
return;
}
// set the altitude or StdZ dimension of the layer corresponding to the slider's thumb location
const multidimensionalDefinition = layer.multidimensionalDefinition;
// find the stdZ dimension definition from the layer's multidimensionalDefinition
const depthDef = multidimensionalDefinition.find((def) => def.dimensionName === "StdZ");
if (dimensionName === "StdZ") {
// set the slider thumb to the first altitude found in the StdZ altitude
if (depthDef.values[0] === sliderData.value) {
return;
}
depthDef.values[0] = sliderData.value;
}
layer.multidimensionalDefinition = multidimensionalDefinition;
};