go-staticmaps is a golang library that allows you to create nice static map images from OpenStreetMap tiles, along with markers of different size and color, as well as paths and colored areas.

go-staticmaps comes with a command line tool called create-static-map for use in shell scripts, etc.

How?

Installation

Installing go-staticmaps is as easy as

go get -u github.com/flopp/go-staticmaps

Library Usage

Create a 400x300 pixel map with a red marker:

import (
  "image/color"

  "github.com/flopp/go-staticmaps"
  "github.com/fogleman/gg"
  "github.com/golang/geo/s2"
)

func main() {
  ctx := sm.NewContext()
  ctx.SetSize(400, 300)
  ctx.AddMarker(sm.NewMarker(s2.LatLng{52.514536, 13.350151}, color.RGBA{0xff, 0, 0, 0xff}, 16.0))

  img, err := ctx.Render()
  if err != nil {
    panic(err)
  }

  if err := gg.SavePNG("my-map.png", img); err != nil {
    panic(err)
  }
}

See GoDoc for a complete documentation and the source code of the command line tool for an example how to use the package.

Command Line Usage

Usage:
  create-static-map [OPTIONS]

Creates a static map

Application Options:
      --width=PIXELS       Width of the generated static map image (default: 512)
      --height=PIXELS      Height of the generated static map image (default: 512)
  -o, --output=FILENAME    Output file name (default: map.png)
  -t, --type=MAPTYPE       Select the map type; list possible map types with '--type list'
  -c, --center=LATLNG      Center coordinates (lat,lng) of the static map
  -z, --zoom=ZOOMLEVEL     Zoom factor
  -m, --marker=MARKER      Add a marker to the static map
  -p, --path=PATH          Add a path to the static map
  -a, --area=AREA          Add an area to the static map

Help Options:
  -h, --help               Show this help message

General

The command line interface tries to resemble Google's Static Maps API. If --center or --zoom are not given, good values are determined from the specified markers and paths.

Markers

The --marker option defines one or more map markers of the same style. Use multiple --marker options to add markers of different styles.

--marker MARKER_STYLES|LATLNG|LATLNG|...

LATLNG is a comma separated pair of latitude and longitude, e.g. 52.5153,13.3564.

MARKER_STYLES consists of a set of style descriptors separated by the pipe character |:

color:COLOR - where COLOR is either of the form 0xRRGGBB, 0xRRGGBBAA, or one of black, blue, brown, green, orange, purple, red, yellow, white (default: red)
size:SIZE - where SIZE is one of mid, small, tiny, or some number > 0 (default: mid)
label:LABEL - where LABEL is an alpha numeric character, i.e. A-Z, a-z, 0-9; (default: no label)

Paths

The --path option defines a path on the map. Use multiple --path options to add multiple paths to the map.

--path PATH_STYLES|LATLNG|LATLNG|...

--path PATH_STYLES|gpx:my_gpx_file.gpx

PATH_STYLES consists of a set of style descriptors separated by the pipe character |:

color:COLOR - where COLOR is either of the form 0xRRGGBB, 0xRRGGBBAA, or one of black, blue, brown, green, orange, purple, red, yellow, white (default: red)
weight:WEIGHT - where WEIGHT is the line width in pixels (defaut: 5)

Areas

The --area option defines a closed area on the map. Use multiple --area options to add multiple areas to the map.

--area AREA_STYLES|LATLNG|LATLNG|...

AREA_STYLES consists of a set of style descriptors separated by the pipe character |:

color:COLOR - where COLOR is either of the form 0xRRGGBB, 0xRRGGBBAA, or one of black, blue, brown, green, orange, purple, red, yellow, white (default: red)
weight:WEIGHT - where WEIGHT is the line width in pixels (defaut: 5)
fill:COLOR - where COLOR is either of the form 0xRRGGBB, 0xRRGGBBAA, or one of black, blue, brown, green, orange, purple, red, yellow, white (default: none)

Examples

Basic Maps

Centered at "N 52.514536 E 13.350151" with zoom level 10:

$ create-static-map --width 600 --height 400 -o map1.png -c "52.514536,13.350151" -z 10

A map with a marker at "N 52.514536 E 13.350151" with zoom level 14 (no need to specify the map's center - it is automatically computed from the marker(s)):

$ create-static-map --width 600 --height 400 -o map2.png -z 14 -m "52.514536,13.350151"

A map with two markers (red and green). If there are more than two markers in the map, a good zoom level can be determined automatically:

$ create-static-map --width 600 --height 400 -o map3.png -m "red|52.514536,13.350151" -m "green|52.516285,13.377746"

Create a map of the Berlin Marathon

create-static-map --width 800 --height 600 \
  --marker "color:green|52.5153,13.3564" \
  --marker "color:red|52.5160,13.3711" \
  --output "berlin-marathon.png" \
  --path "color:blue|weight:2|gpx:berlin-marathon.gpx"

Create a map of the US capitals

create-static-map --width 800 --height 400 \
  --output "us-capitals.png" \
  --marker "color:blue|size:tiny|32.3754,-86.2996|58.3637,-134.5721|33.4483,-112.0738|34.7244,-92.2789|\
    38.5737,-121.4871|39.7551,-104.9881|41.7665,-72.6732|39.1615,-75.5136|30.4382,-84.2806|33.7545,-84.3897|\
    21.2920,-157.8219|43.6021,-116.2125|39.8018,-89.6533|39.7670,-86.1563|41.5888,-93.6203|39.0474,-95.6815|\
    38.1894,-84.8715|30.4493,-91.1882|44.3294,-69.7323|38.9693,-76.5197|42.3589,-71.0568|42.7336,-84.5466|\
    44.9446,-93.1027|32.3122,-90.1780|38.5698,-92.1941|46.5911,-112.0205|40.8136,-96.7026|39.1501,-119.7519|\
    43.2314,-71.5597|40.2202,-74.7642|35.6816,-105.9381|42.6517,-73.7551|35.7797,-78.6434|46.8084,-100.7694|\
    39.9622,-83.0007|35.4931,-97.4591|44.9370,-123.0272|40.2740,-76.8849|41.8270,-71.4087|34.0007,-81.0353|\
    44.3776,-100.3177|36.1589,-86.7821|30.2687,-97.7452|40.7716,-111.8882|44.2627,-72.5716|37.5408,-77.4339|\
    47.0449,-122.9016|38.3533,-81.6354|43.0632,-89.4007|41.1389,-104.8165"

Create a map of Australia

...where the Northern Territory is highlighted and the capital Canberra is marked.

create-static-map --width 800 --height 600 \
  --center="-26.284973,134.303764" \
  --output "australia.png" \
  --marker "color:blue|-35.305200,149.121574" \
  --area "color:0x00FF00|fill:0x00FF007F|weight:2|-25.994024,129.013847|-25.994024,137.989677|-16.537670,138.011649|\
    -14.834820,135.385917|-12.293236,137.033866|-11.174554,130.398124|-12.925791,130.167411|-14.866678,129.002860"

Acknowledgements

Besides the go standard library, go-staticmaps uses

MapQuest, Thunderforest, OpenTopoMap, and Stamen as map tile providers
Go Graphics for 2D drawing
S2 geometry library for spherical geometry calculations
appdirs for platform specific system directories
gpxgo for loading GPX files
go-coordsparser for parsing geo coordinates

License

Use of this source code is governed by a MIT-style license that can be found in the LICENSE file.