AI-generated Key Takeaways
-
Map.addLayer()
overlays Earth Engine objects like images and features onto the map as a new layer. -
Visualization parameters can be customized for images and features, controlling aspects like color, opacity, and stretch.
-
This function accepts Earth Engine objects (Image, Feature, Geometry, Collections) and styling options to control their visual representation.
-
Layers can be named and controlled for initial visibility.
-
The function returns the added layer as a
ui.Map.Layer
object for further manipulation.
Returns the new map layer.
Usage | Returns |
---|---|
Map.addLayer(eeObject, visParams, name, shown, opacity) | ui.Map.Layer |
Argument | Type | Details |
---|---|---|
this: ui.map | ui.Map | The ui.Map instance. |
eeObject | Collection|Feature|Image|MapId | The object to add to the map. |
visParams | FeatureVisualizationParameters|ImageVisualizationParameters, optional | The visualization parameters. For Images and ImageCollection, see ee.data.getMapId for valid parameters. For Features and FeatureCollections, the only supported key is "color", as a 6-character hex string in the RRGGBB format. |
name | String, optional | The name of the layer. Defaults to "Layer N". |
shown | Boolean, optional | A flag indicating whether the layer should be on by default. |
opacity | Number, optional | The layer's opacity represented as a number between 0 and 1. Defaults to 1. |
Examples
Code Editor (JavaScript)
// Define a ui.Map widget and add it to the cleared ui.root. var map = ui.Map(); ui.root.clear(); ui.root.add(map); map.setCenter(-121.87, 37.44, 9); // A Sentinel-2 surface reflectance image. var image = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG'); // Set multi-band RGB image visualization parameters. If the "bands" parameter // is not defined, the first three bands are used. var rgbVis = { bands: ['B11', 'B8', 'B3'], min: 0, max: 3000 }; map.addLayer(image, rgbVis, 'Multi-band RGB image'); // Set band-specific "min" and "max" properties. var rgbVisBandSpec = { bands: ['B11', 'B8', 'B3'], min: [0, 75, 150], max: [3500, 3000, 2500] }; map.addLayer(image, rgbVisBandSpec, 'Band-specific min/max'); // If you don't specify "min" and "max" properties, they will be determined // from the data type range, often resulting in an ineffective color stretch. map.addLayer(image.select('B8'), null, 'Default visParams'); // If an image layer has already been styled, set "visParams" as null. var imageRgb = image.visualize(rgbVis); map.addLayer(imageRgb, null, 'Pre-styled image'); // Use the "palette" parameter with single-band image inputs to define the // linear color gradient to stretch between the "min" and "max" values. var singleBandVis = { min: 0, max: 3000, palette: ['blue', 'yellow', 'green'] }; map.addLayer(image.select('B8'), singleBandVis, 'Single-band palette'); // Images within ImageCollections are automatically mosaicked according to mask // status and image order. The last image in the collection takes priority, // invalid pixels are filled by valid pixels in preceding images. var imageCol = ee.ImageCollection('COPERNICUS/S2_SR') .filterDate('2021-03-01', '2021-04-01'); map.addLayer(imageCol, rgbVis, 'ImageCollection mosaic'); // FeatureCollection, Feature, and Geometry objects can be styled using the // "color" parameter. var featureCol = ee.FeatureCollection('WCMC/WDPA/current/polygons'); map.addLayer(featureCol, {color: 'purple'}, 'FeatureCollection');