AI-generated Key Takeaways
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Map.addLayer adds a given Earth Engine object to the map as a layer and returns the new map layer.
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The method accepts arguments for the Earth Engine object, optional visualization parameters, layer name, visibility status, and opacity.
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Visualization parameters can be specified for Images, ImageCollections, Features, and FeatureCollections, allowing customization of how the data is displayed on the map.
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Examples demonstrate adding various Earth Engine objects to the map using different visualization options, including multi-band and single-band images, image collections, and feature collections.
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Features and FeatureCollections can be styled using the "color" parameter with a 6-character hex string.
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' );
