Hi OsmAnd developers,

I wanted to get back to the quality problems around hillshades addressed 5 
years ago which have not really changed, at least not in my areas. There 
are weird artifacts at the edges of hillshade tiles and overall the 
hillshades are quite blurred. 

Compare this example of OsmAnd hillshading 
<https://app.box.com/s/pdz4nibi3imn20uwuh3ww1gjpatomgcs> with what is 
possible based on swissALTI3D hillshading at map.geo.admin.ch 
<https://app.box.com/s/tqdjiu0sa0tx1buyaep44pcamymiptmd>. Of course, the 
swissALTI3D hillshade files are too heavy to store hillshades of entire 
countries on a mobile phone.

But when I reduce the quality of the swissALTI3Dhillshade 
<https://app.box.com/s/dqlo0lrkb3smx8hr5klq3hgmalwnr5z8> of this example to 
only 1% of its quality 
<https://app.box.com/s/pojnul7ub20fcau7hp4xbnbfaxbayyb4> the result is 
still way more detailed than the soft OsmAnd haze. Especially where there 
are sharp mountain ridges, the gentle transition of OsmAnd is weird. See 
for instance the ridge at the right-hand side of the screenshot 
(Schindelberghöchi to Habrütispitz). In the OsmAnd screenshot it looks very 
soft and is partially not visible at all. Here a view from Schindelegg 
towards Schindelberghöchi 
<http://www.dplate.de/photos/toggenburg/20171104/wanderweg-schindelbergh%C3%B6chi_023.jpg>
 
showing that it is a sharp ridge. The uppermost 100m of the slope to the 
right are almost vertical rock. 

In the example the 1% quality hillshade JPEG is 6.7 KB in size and covers 
4.77 km * 2.17 km = 10.35 km2. For the 41,285 km2 of Switzerland 26.1 MB of 
these 1% quality hillshade files would be needed. This is *less storage 
need* than today's OsmAnd hillshade tiles consume. The current OsmAnd 
hillshades for Switzerland weigh 46.6 MB. So, there is clear room for 
improvement.

I would love an improvement around hillshades. Thanks for considering.
Peter

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