GaladrielCache

This is a simple map tiles cache/proxy to use on weak computers such as RaspberryPi or NAS. The author uses it in the wi-fi router/GSM modem under OpenWRT on his sailboat Galadriel.
GaladrielCache can be used with any on-line map viewer. OruxMaps is a good choice. GaladrielMap is a good choice too.
Tiles locally stored on OSM z/x/y file structure, so you may use SD with raster maps without a server -- directly on your smartphone in the event of a disaster.

v. 2.9

Contains:

Features
Compatibility
Usage
- OruxMaps configuration
- GaladrielMap configuration
- SignalK
- OSM "slippy map" tilenames
- MBTiles
Install&configure
Prepare SD card to cache
Direct access to the cache
- Mount SD card
- Configure OruxMaps
- Automated mounting in Android with 3C toolbox
Loader
- Using Loader to copy part of the cache
Cache control (API)
- Get maps list
- Get map info
- Create loader job
- Get loader status
Utilites
- clearCache
- checkSources
- Coverage
Support

Features:

User-defined internet map sources, with versioning, if needed.
Flexible and robust tile loading with proxy support.
Prior loading of large zoom levels.
Asynchronous cache freshing.
Separated robust loader.
Serves MBTiles local maps.

But no reprojection. Map projection is a client application problem.

Compatibility

Linux, PHP < 8. The cretinous decisions made at PHP 8 do not allow the GaladrielCache to work at PHP 8, and I do not want to follow these decisions.

Usage:

_tiles.php?z=Zoom&x=X_tile_num&y=Y_tile_num&r=mapName

OruxMaps configuration

To use GaladrielCache with OruxMaps, add map definitions to OruxMaps onlinemapsources.xml, for example -- Yandex Sat map:

<onlinemapsource uid="1055">
<name>Yandex Sat via my proxy (SAT)</name>
<url><![CDATA[http://192.168.1.1/tileproxy/tiles.php?z={$z}&x={$x}&y={$y}&r=yasat.EPSG3395]]></url>
<minzoom>5</minzoom>
<maxzoom>19</maxzoom>
<projection>MERCATORELIPSOIDAL</projection>
<cacheable>1</cacheable>
<downloadable>0</downloadable>
</onlinemapsource>

Where: 192.168.1.1 - your server
/tileproxy/tiles.php - cache/proxy
and yasat.EPSG3395 - your custom map source name.
Try it to other maps.

ATTENTION! You MUST configure your MAP VIEWER for the use of specific projection!
(<projection>MERCATORELIPSOIDAL</projection> in the example above)
The GaladrielCache knows nothing about projections, it's store tiles only.

GaladrielMap configuration

To use GaladrielMap with GaladrielCache -- set $tileCachePath in GaladrielMap's params.php file.

SignalK

To use GaladrielCache in SignalK just configure charts-plugin to use every map available in the GaladrielCache.
For examle, for OpenTopoMap specify URL to http://you_server/tileproxy/tiles.php?z={z}&x={x}&y={y}&r=OpenTopoMap

OSM "slippy map" tilenames

Some applications (AvNav?) cannot use tiles other than in OSM "slippy map" tilenames format. To use the GaladrielCache with these applications, you can configure the Apache2 as follows:

<IfModule rewrite_module>
    RewriteEngine On
    RewriteRule ^tiles/(.+)/([0-9]+)/([0-9]+)/([0-9.a-z]+)$ tiles.php?r=$1&z=$2&x=$3&y=$4
</IfModule>

and refer to the cache:
_tiles/map_Name/Zoom/X_tile/Ytile
with or without extension.

MBTiles

The file with map on mbtiles format must have .mbtiles extension and located in $tileCacheDir directory. The map description file must have same name as map file, but with .php extension of course, and similarly to other such files be locate in mapsources/ directory.
It doesn't matter to the GaladrielCache whether vector or raster tiles are in the map file. The corresponding configuration should be in the map description file.

Install&configure

You must have a web server with php support. Just copy.
Paths and other settings are described in params.php Custom sources are in mapsources/* Help about map sources are in mapsources/mapsources.md

Prepare SD card to cache

# mkfs.ext4 -O 64bit,metadata_csum -b 4096 -i 4096 /dev/sdb1

-b 4096 -i 4096 set block to 4096 bytes and increase i-nodes to max.
-O 64bit,metadata_csum needs for compability with old Android devices.
/dev/sdb1 - your SD card partition.
However, default formatting in vfat allows you to store a sufficient amount of tiles on the map for practical purposes.

Direct access to the cache

If you server dead, but you have a rooted Android phone or tablet, you may use raster tiles directly:

Mount SD card

remove SD card with the cache from the server
insert the SD card with cache to Android device on Android device with terminal:
Open terminal. Try:
```
# mount -o rw,remount /
# mkdir /data/mySDcard 
# chown 1000:1000 /data/mySDcard
# chmod 774 /data/mySDcard
# mount -o ro,remount /
# mount -rw -t ext4 /dev/block/mmcblk1p1 /data/mySDcard
```
This creates mount point and mounts your SD card. There to, so you have all maps on your Android device.
There:
/dev/block/mmcblk1p1 - partition wint cache on you SD card. To find it, try
```
$ ls /dev/block
```
Last mmcblk - most probably your SD card.
/data/mySDcard - mount point

Depending on how you obtain root, the command mount may be written as

# su --mount-master -c 'busybox mount -rw -t ext4 /dev/block/mmcblk1p1 /data/mySDcard'

Configure OruxMaps:

Modify oryxmaps/mapfiles/onlinemapsources.xml by add:

<onlinemapsource uid="1052">
<name>Navionics layer from local dir (NAV)</name>
<url><![CDATA[file://data/mySDcard/tiles/navionics_layer/{$z}/{$x}/{$y}.png]]></url> 
<minzoom>12</minzoom>
<maxzoom>18</maxzoom>
<projection>MERCATORESFERICA</projection>
<cacheable>0</cacheable>
<downloadable>0</downloadable>
</onlinemapsource>
<onlinemapsource uid="1054">
<name>OpenTopoMap from local dir (TOPO)</name>
<url><![CDATA[file://data/mySDcard/tiles/OpenTopoMap/{$z}/{$x}/{$y}.png]]></url> 
<minzoom>5</minzoom>
<maxzoom>18</maxzoom>
<projection>MERCATORESFERICA</projection>
<cacheable>0</cacheable>
<downloadable>0</downloadable>
</onlinemapsource>

and other maps by same way.
There /tiles/ - path to cache from the SD card root.

Automated mounting in Android with 3C toolbox

With 3C toolbox you can automate the mounting when the device boots.

Create file:
_01mountExtSDcard
```
#!/system/bin/sh
```

EXT_SD_DIRECTORY=/data/mySDcard;

if [ ! -d $EXT_SD_DIRECTORY ]; then mount -o rw,remount / mkdir $EXT_SD_DIRECTORY; chown 1000:1000 $EXT_SD_DIRECTORY; chmod 774 $EXT_SD_DIRECTORY; mount -o ro,remount / fi mount -rw -t ext4 /dev/block/mmcblk1p1 $EXT_SD_DIRECTORY

2. Place it in home directory by path <br>
`Android/data/ccc71.at.free/scripts/` or <br>
`Android/data/ccc71.at/scripts/` 
3. Open **3C toolbox** 
4. Go Tools - Script editor 
5. Mark _01_mountExtSDcard_ as runed in boot

## Loader
GaladrielCache includes a dumb tile loader. Create a csv job file with map_source_name.zoom as a name and x,y strings as content and place it in `loaderjobs/` directory. Run _startLoaderDaemon_ (or _php loaderSched.php_ for foreground) in cli. [GaladrielMap](https://github.com/VladimirKalachikhin/Galadriel-map) has a GUI for it.  
To stop Loader run _stopLoader_ or delete Loader job files bouth from `loaderjobs/` and `loaderjobs/inWork/` directories.

For example:  
_OpenSeaMap.9_

295,145 296,145 296,144 295,144 295,143 296,143


Will be downloaded OpenSeaMap within the specified tiles from zoom 9 to $loaderMaxZoom from _params.php_.  

Tile loader may use any number of threads to load, and use cron for robust download.  
You may use a [GaladrielMap](https://github.com/VladimirKalachikhin/Galadriel-map/tree/master) for control Loader. Job files, created by [GaladrielMap](https://github.com/VladimirKalachikhin/Galadriel-map/tree/master), saved in `loaderjobs/oldjobs` for backup.

### Using Loader to copy part of the cache
Add to the first line of csv job file some copy command. In this case, Loader starts this command instead of loading tile. 
This first line must be started from #.  
For example:  
_OpenSeaMap.9_

mkdir -p /mnt/mySDcard/RegionTileCache/$r/$z/$x/ && cp -Hpu $tileCacheDir/$r/$z/$x/$y /mnt/mySDcard/RegionTileCache/$r/$z/$x/