Creating Mobile-first Offline Maps using Authoritative Trails Data Offline Maps for Mobile MakingRob Chohan Maps That, SanAre Mobile Diego First CTO, ePi Rational, Inc More info & animated slides at RobLabs.com/mobile1st Mobile First Maps by �π Maps

• Mobile First — Maps are natively offline

• Using local assets for Raster and tiles

• Since map tiles are local, there is no server • No privacy issues • No analytics nor tracking ensures full privacy El Capitan Quadrangle •Viewed with a standard PDF viewer •Downloaded from https://nationalmap.gov •GeoPDF designed to be printed at 22.75 x 29 inches •Updated in 2016, https://prd-tnm.s3.amazonaws.com/StagedProducts/Maps/USTopo/1/22271/7536518.pdf (GIF) Layers in Acrobat • Details on layers and GDAL tools to process at RobLabs.com/gdal-geopdf Shaded Relief + National Map Geographic Names NPS Trails + Shaded Relief + National Map Geographic Names 40 Foot Contours + Shaded Relief + National Map Geographic Names 40 Foot Contour Labels + Shaded Relief + National Map Geographic Names Open Map Tiles + Shaded Relief + National Map Geographic Names + NPS Trails Authoritative Map Data FSTopo and FSGeodata • GeoPDF, GeoTIFF and Vector data • https://data.fs.usda.gov/geodata Boundary Waters & Superior National Forest Available US Topos https://viewer.nationalmap.gov/basic/? basemap=b1&category=ustopo&title=US%20Topo%20Download#productGroup Search The National Map https://viewer.nationalmap.gov/basic/ #productGroupSearch (GIF) Vector Contour (GIF) Vector Contour + National Trails

• There is a visual anomaly that looks like a vertical knife edge of data 40 foot contours in this quad

80 foot contours in this quad Vertical Knife Edge •Zooming in reveals a difference in contour intervals •For this we had to filter using data reduction techniques But we are missing trails in Yosemite Valley (GIF) USGS & NPS Data • The National Map • Contours, National Trails, Geographic Names • National Park Service, Yosemite Trails • IRMA, https://irma.nps.gov/DataStore/Search/Quick • YOSE trails, https://irma.nps.gov/DataStore/Reference/Profile/2180706 NPM Symbol Library https://www.nps.gov/maps/tools/symbol-library/ Raster Shaded Relief + National Map Geographic Names Rendering Raster Data •Raster data is `tiled` and compressed with WebP •WebP compress about 3 times smaller when compared to PNG •https://developers.google.com/speed/webp •Tiling is performed with the GDAL suite of tools from OSGEO, gdal2tiles.py Not all Web Browsers support WebP • But since we are Mobile First, this is a don’t care

• We built the WebP reader into our Mobile SDK for iOS

• See our code and how to include a WebP reader for mobile • https://github.com/roblabs/ mapbox-gl-native

https://developers.google.com/speed/webp/faq Rendering Vector Data • Conversion of Shapefiles to Mapbox Vector Tile specification • Using the Mapbox command line tools, including tippecanoe Search on the Apple Appstore ‘epi offline maps’ •wilderness.net — Wilderness boundaries •USGS — Shaded Relief, contours •USFS — Trails and roads •NPS — Trails and Icons •Open Map Tiles — Roads, water •Mapbox — Mobile SDK, specifications for MBTiles, Mapbox Vector Tiles, Tools and other open source goodness Summary of Links RobLabs.com/mobile1st

• Search ‘epi offline maps’ • iOS — https://itunes.apple.com/us/developer/epi-rational-inc./id416401310 • Android — https://play.google.com/store/search?q=com.roblabs.papermaps&=apps • Open Map Tiles • open source mapping made for self hosting — http://openMapTiles.org • Mapbox • iOS SDK for rendering raster & vector map data — https://github.com/roblabs/mapbox-gl-native • Tippecanoe, converting to Mapbox Vector Tiles — https://github.com/mapbox/tippecanoe • USGS • US Topo & The National Map — http://nationalmap.gov • Forest Service • https://data.fs.usda.gov/geodata/edw/datasets.php • https://data.fs.usda.gov/geodata/ • NPS • https://public-nps.opendata.arcgis.com