Using Orux SQLites as overlays

Michael Bechtold shared this question 3 years ago
Answered

Hi Menion,

for whatever reason, the Orux DB in many cases is much smaller than any other SQLite format for the exact same tiles and display quality. Hence it would be nice to allow that SQLite for overlays, too.

Why is that denied ?

TXs and cheers

Michael

Comments (7)

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Just guessing... but maybe your oruxmaps sqlites have jpeg tiles instead of the more commonly used png? That would be a reason for smaller sizes... not for being incompatible with Locus. Locus handles jpeg tiles nicely as far as I know.


JPEG is the preferred tile format on Android anyway. There is more hardware acceleration going on behind the scenes afaik. Mobac can e.g. be told to recompress to jpeg when downloading. Would be great if the Locus built-in map downloader and also the online map tile cache could optionally to that as well. It's only a minor addition but potentially saves 50% of SD memory without any visible artefacts. Might even be a little faster and use less battery afterwards.

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Good day Michael,


format, that is used by Orux allows to define more map projections, not just basic projection aka "Google style". Locus currently do not do any tile re-projection on the fly, so I've disabled this type of map for overlays at all.


Thanks for understanding.

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Just another little reminder of how useful OpenGL could be. Reprojection of anything to anything on the fly, not a single CPU cycle wasted.

Sorry... Couldn't resist... :)... just read an interesting article on how they do it (set up transformation matrices) in OpenLayers. Interesting triangle polygon stuff...

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I see. TXs for the background, Menion.


With joeloc's hint (to use jpg) also the other SQLite DBs shrink in size, so I can achieve my objective.

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Would be great if Locus offered to "jpegize" everything automagically, cached tiles, downloaded maps, existing sqlite maps, jusz everything. I really can't find a valid reason for PNG tiles on mobile... they are simply an incredible waste of space. And with all those funny new phones without sdcard slots, space is valuable again.

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Hopefully Menion's current studies of OpenGL will bar fruit here, too :-)

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