dalalsunil1986 / im-map-tiles

Map Tile Generator for Google Maps, Leaflet and other Map libraries using ImageMagick

im-map-tiles

Map Tile Generator for Google Maps, Leaflet and other Map libraries using ImageMagick.

Dependencies

• ImageMagick
• Bash

Usage

$ ./im-map-tiles.sh 
Usage: ./im-map-tiles.sh SOURCE_IMAGE TILES_DESTINATION_DIR [TILE_FORMAT]

SOURCE_IMAGE must exist.
TILE_FORMAT defaults to 'png'.

Output will take the format of:

${TILES_DESTINATION_DIR}/${ZOOM_LEVEL}/tile_${X}_${Y}.${TILE_FORMAT}

e.g.

./tiles/1/tile_0_1.png
./tiles/3/tile_2_3.png
./tiles/5/tile_2_3.png
...

${ZOOM_LEVEL} will start at 0 and go up to the maximum zoom possible for the ${SOURCE_IMAGE} rounding up to the next zoom level. A ${SOURCE_IMAGE} with dimensions 2048x2048 will go up to 4 whereas an image with 3000x3000 will go up to 5. This is done to make the most out of the level of detail in the image without enlargening too much.

Each tile has a dimension of 256x256 and each ${ZOOM_LEVEL} goes up in dimensions of 2^${ZOOM_LEVEL} (i.e. 1x1, 2x2, 4x4, 8x8, 16x16 etc.). So overall, for each zoom level, the resulting map resolution will be 256x256, 512x512, 1024x1024, 2048x2048 and so on.

If you're using Leaflet, I suggest you set this maximum zoom as your map.maxNativeZoom so you can have higher zoom levels without the need to download larger, low quality, upscaled tiles.

If a ${ZOOM_LEVEL} directory already exists, it will be skipped.

License

MIT