Shadow simulator for Leaflet. Visualize sunlight and shadow on a map for any date and time of year.
In a browser:
<script src="https://unpkg.com/leaflet-shadow-simulator/dist/leaflet-shadow-simulator.umd.min.js"></script>
Using npm:
npm i leaflet-shadow-simulator --save
In a browser:
<link rel="stylesheet" href="https://unpkg.com/[email protected]/dist/leaflet.css" />
<script src="https://unpkg.com/[email protected]/dist/leaflet.js"></script>
<script src="https://unpkg.com/leaflet-shadow-simulator/dist/leaflet-shadow-simulator.umd.min.js"></script>
<script>
var map = L.map("mapid");
const shadeMap = L.shadeMap({
date: new Date(), // display shadows for current date
color: '#01112f', // shade color
opacity: 0.7, // opacity of shade color
apiKey: "XXXXXX", // obtain from https://shademap.app/about/
terrainSource: {
tileSize: 256, // DEM tile size
maxZoom: 15, // Maximum zoom of DEM tile set
getSourceUrl: ({ x, y, z }) => {
// return DEM tile url for given x,y,z coordinates
return `https://s3.amazonaws.com/elevation-tiles-prod/terrarium/${z}/${x}/${y}.png`
},
getElevation: ({ r, g, b, a }) => {
// return elevation in meters for a given DEM tile pixel
return (r * 256 + g + b / 256) - 32768
}
},
}).addTo(map);
// advance shade by 1 hour
shadeMap.setDate(new Date(Date.now() + 1000 * 60 * 60));
// sometime later...
// ...remove layer
shadeMap.remove();
</script>
Using Node.js:
import * as L from 'leaflet'
import ShadeMap from 'leaflet-shadow-simulator';
const map = L.map("mapid");
const shadeMap = new ShadeMap({
date: new Date(), // display shadows for current date
color: '#01112f', // shade color
opacity: 0.7, // opacity of shade color
apiKey: "XXXXXX", // obtain from https://shademap.app/about/
terrainSource: {
tileSize: 256, // DEM tile size
maxZoom: 15, // Maximum zoom of DEM tile set
getSourceUrl: ({ x, y, z }) => {
// return DEM tile url for given x,y,z coordinates
return `https://s3.amazonaws.com/elevation-tiles-prod/terrarium/${z}/${x}/${y}.png`
},
getElevation: ({ r, g, b, a }) => {
// return elevation in meters for a given DEM tile pixel
return (r * 256 + g + b / 256) - 32768
}
},
}).addTo(map);
// advance shade by 1 hour
shadeMap.setDate(new Date(Date.now() + 1000 * 60 * 60));
// sometime later
// ...remove layer
shadeMap.remove();
Property name | Type | Default value | Comment |
---|---|---|---|
apiKey |
String |
'' |
See https://shademap.app/about/ |
date |
Date |
new Date() |
Sun's position in the sky is based on this date |
color |
String |
#000 |
3 or 6 digit hexadecimal number |
opacity |
Number |
0.3 |
|
showExposure |
Boolean |
false |
If set to true, display full-day sun exposure for date (Note: requires suncalc) |
terrainSource |
Object |
See terrainSource | Specify DEM or DSM tiles containing terrain elevation data |
getFeatures |
Function |
See getFeatures | Returns GeoJSON of objects, such as buildings, to display on the map |
An object describing a DEM tile set to use for terrain shadows
Property name | Type | Default value | Comment |
---|---|---|---|
maxZoom |
Number |
15 |
Max zoom for custom DEM tile source |
tileSize |
Number |
256 |
Tile size for custom DEM tile source |
sourceUrl |
Function |
Returns tile encoding 0m elevation for all locations |
Returns url of DEM tile for given (x, y, z) coordinate |
getElevation |
Function |
return (r * 256 + g + b / 256) - 32768 |
Returns elevation in meters for each (r,g,b,a) pixel of DEM tile |
A global dataset providing bare-earth terrain heights, tiled for easy usage and provided on S3 - More info
{
tileSize: 256,
maxZoom: 15,
getSourceUrl: ({x, y, z}) => {
return `https://s3.amazonaws.com/elevation-tiles-prod/terrarium/${z}/${x}/${y}.png`;
},
getElevation: ({r, g, b, a}) => {
return (r * 256 + g + b / 256) - 32768;
}
}
Mapbox Terrain-DEM v1 is a Mapbox-provided raster tileset is a global elevation layer. This tileset contains raw height values in meters in the Red, Green, and Blue channels of PNG tiles that can be decoded to raw heights in meters - More info
{
tileSize: 256,
maxZoom: 15,
getSourceUrl: ({x, y, z}) => {
return `https://${subdomain}.tiles.mapbox.com/raster/v1/mapbox.mapbox-terrain-dem-v1/${z}/${x}/${y}.webp?sku=101wuwGrczDtH&access_token=${MAPBOX_API_KEY}`;
},
getElevation: ({r, g, b, a}) => {
return -10000 + ((r * 256 * 256 + g * 256 + b) * .1);
}
}
Returns a GeoJSON collection of features whose shadows will be displayed on the map. Currently only supports Polygon
and MultiPolygon
.
getFeatures: () => {
return [{
"type": "Feature",
"geometry": {
"type": "Polygon",
"coordinates": [
[29.8148007, 31.2240349],
[29.8248007, 31.2240349],
[29.8248007, 31.2140349],
[29.8148007, 31.2140349],
]
},
"properties": {
"height": 1000,
"render_height": 1000,
"name": "Alexandria column"
}
},
},
setDate(date: Date)
- update shade layer to reflect new date
setColor(color: String)
- change shade color
setOpacity(opacity: Number)
- change shade opacity
setShowExposure(show: Boolean)
- toggle between shadows and full-day sun exposure for date
(Note: requires suncalc)
getHoursOfSun(x: Number, y: Number)
- if sun exposure mode enabled, returns the hours of sunlight for a given pixel on the map