terrain-tiles

Terrain Tiles

Contains terrain tiles in the N047E011 region. These tiles are made to be used with our terrain demo page, which centers around Innsbruck Austria [11.40416, 47.26475]

How to use the demo Terrain Tiles

1.) Include the terrain tiles in your maps list of sources.

terrain_source: {
	type: 'raster-dem',
	url: 'https://demotiles.maplibre.org/terrain-tiles/tiles.json'
},
hillshade_source: {
	type: 'raster-dem',
	url: 'https://demotiles.maplibre.org/terrain-tiles/tiles.json'
},

2.) Use the terrain tile source for 3d terrain in you style.

terrain: {
	source:  'terrain_source',
	exaggeration:  1
}

3.) Use the terrain tile source for hillshade.

{
	id:  'hills',
	type:  'hillshade',
	source:  'hillshade_source',
	layout: {'visibility':  'visible'},
	paint: {'hillshade-shadow-color':'#473B24'}
}

4.) With all of these combined, the style should look something like this.

style: {
	version:  8,
	sources: {
		osm: {
			type:  'raster',
			tiles: ['https://tile.openstreetmap.org/{z}/{x}/{y}.png'],
			tileSize:  256,
			attribution:  '© OpenStreetMap Contributors',
			maxzoom:  19
		},
		terrain_source: {
			type:  'raster-dem',
			url:  'https://demotiles.maplibre.org/terrain-tiles/tiles.json'
		},
		hillshade_source: {
			type:  'raster-dem',
			url:  'https://demotiles.maplibre.org/terrain-tiles/tiles.json'
		},
	},
	layers: [
		{
			id:  'osm',
			type:  'raster',
			source:  'osm'
		},
		{
			id:  'hills',
			type:  'hillshade',
			source:  'hillshade_source',
			layout: {'visibility':  'visible'},
			paint: {'hillshade-shadow-color':'#473B24'}
		}
	],
	terrain: {
		source:  'terrain_source',
		exaggeration:  1
	}
}

5.) With all this in place, view it by going to Innsbruck, Austria [11.40416, 47.26475] on your map. These tiles only cover a 1 degree x 1 degree area, so they are only viewable in the N047E011 region.

Terrain Tile Generation

1.) This terrain was made from JAXA AW3D30 DSM files. To get these yourself, you must register for a free account at https://www.eorc.jaxa.jp/ALOS/en/dataset/aw3d30/aw3d30_e.htm .

2.) Once registered, go to the JAXA download page and get the ZIP files which match the region you would like to map.

3.) From each zip file you downloaded, extract the file that ends in "_DSM.tif" and place it into a folder.

4.) Run the following bash script. Make sure the INPUT_DIR directory is the folder where you placed the "_DSM.tif" files. This requires proj, gdal, and rio-rgbify to be installed.

#!/bin/bash

INPUT_DIR=./input
OUTPUT_DIR=./rio
vrtfile=${OUTPUT_DIR}/jaxa_terrainrgb_0-12.vrt
vrtfile2=${OUTPUT_DIR}/jaxa_terrainrgb_0-12_warp.vrt
mbtiles=${OUTPUT_DIR}/jaxa_terrainrgb_0-12.mbtiles

[ -d "$OUTPUT_DIR" ] || mkdir -p $OUTPUT_DIR || { echo "error: $OUTPUT_DIR " 1>&2; exit 1; }

#rm rio/*
gdalbuildvrt -overwrite -srcnodata -9999 -vrtnodata -9999 ${vrtfile} ${INPUT_DIR}/*_DSM.tif
gdalwarp -r cubicspline -t_srs EPSG:3857 -dstnodata 0 -co COMPRESS=DEFLATE ${vrtfile} ${vrtfile2}
rio rgbify -b -10000 -i 0.1 --min-z 0 --max-z 12 -j 24 --format png ${vrtfile2} ${mbtiles}

#CREATE UNIQUE INDEX tile_index on tiles (zoom_level, tile_column, tile_row);
sqlite3 ${mbtiles} 'CREATE UNIQUE INDEX tile_index on tiles (zoom_level, tile_column, tile_row);'

5.) You now should have a TerrainRGB mbtiles file in the OUTPUT_DIR of the script.

6.) Use a sqlite editor to add in attribution, name, description. The attribution is important to comply with the JAXA use policy

7.) To make the mbtiles into flat files (optional), use a tool like mbutil to extract them.

mb-util jaxa_terrainrgb_0-12.mbtiles terrainrgb

The tiles.json file was generated by running tileserver-gl with the .mbtiles file as an input.

Data Source

Japan Aerospace Exploration Agency (JAXA) ALOS Global Digital Surface Model "ALOS World 3D - 30m (AW3D30)" https://earth.jaxa.jp/en/data/policy/