Geopdf files in OruxMaps
Posted: Wed 19 Jul, 2017 12:50 pm
OK, I have started a new thread because keithy and wildwanderer are contributing so much useful information on this topic and I am sure interest will continue way beyond the original topic of the other thread at http://bushwalk.com/forum/viewtopic.php?f=21&t=25950.
To summarise:
You need the latest oruxmaps version 7.017 for geopdf to work.
NSW etopo maps can be downloaded from http://maps.six.nsw.gov.au/etopo.html but currently give blinking problems for some users (including me). They look identical in style and resolution to the downloaded wms rasters from six.
QLD geopdf maps can be downloaded from http://qtopo.dnrm.qld.gov.au/mobile/ (then follow: Click here to ... > Download a standard map sheet > 1:25,000 > Next > Search By (choose either Name or Number) > Next > enter your map Name or Number > Download Map). They work without blinking for me. They are higher in resolution than the downloaded wms rasters from qtopo.
An advantage over wms is that when geopdf files work well they fill the whole screen at any zoom level.
A disadvantage for geopdf maps that are standard mapsheets is that they include margin information of variable width, and they are georeferenced across the whole image including the map border. Therefore, when you come to the edge of the map you will see margin info rather than the adjacent map unless you manually select the adjacent map in OM. There may be workarounds or alternatives such as cropping and saving with geopdf references, or downloading the map areas without sheet margins - but I have not worked them out.
keithy has explained some file conversion options as workarounds for problem files, and I believe that Orux is continuing to tweak geopdf capability.
I am not sure how total size will compare with wms downloads at the same resolution, but this may not be a problem if you have a suitably large SD card.
I can see that there might be a lot of geopdf sheets with not very useful names, so avid users might find it useful to have a separate subdirectory for them in OM (under mapfiles), and to rename for easy recognition (like TyalgumQLD_9541-31.pdf instead of QTopo_9541-31.pdf).
Perhaps other forum users will post download links or usage tips.
To summarise:
You need the latest oruxmaps version 7.017 for geopdf to work.
NSW etopo maps can be downloaded from http://maps.six.nsw.gov.au/etopo.html but currently give blinking problems for some users (including me). They look identical in style and resolution to the downloaded wms rasters from six.
QLD geopdf maps can be downloaded from http://qtopo.dnrm.qld.gov.au/mobile/ (then follow: Click here to ... > Download a standard map sheet > 1:25,000 > Next > Search By (choose either Name or Number) > Next > enter your map Name or Number > Download Map). They work without blinking for me. They are higher in resolution than the downloaded wms rasters from qtopo.
An advantage over wms is that when geopdf files work well they fill the whole screen at any zoom level.
A disadvantage for geopdf maps that are standard mapsheets is that they include margin information of variable width, and they are georeferenced across the whole image including the map border. Therefore, when you come to the edge of the map you will see margin info rather than the adjacent map unless you manually select the adjacent map in OM. There may be workarounds or alternatives such as cropping and saving with geopdf references, or downloading the map areas without sheet margins - but I have not worked them out.
keithy has explained some file conversion options as workarounds for problem files, and I believe that Orux is continuing to tweak geopdf capability.
I am not sure how total size will compare with wms downloads at the same resolution, but this may not be a problem if you have a suitably large SD card.
I can see that there might be a lot of geopdf sheets with not very useful names, so avid users might find it useful to have a separate subdirectory for them in OM (under mapfiles), and to rename for easy recognition (like TyalgumQLD_9541-31.pdf instead of QTopo_9541-31.pdf).
Perhaps other forum users will post download links or usage tips.