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stamen / terrain-classic

World-wide CartoCSS port of Stamen's classic terrain style
ISC License
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Blurriness and missing place names #88

Open turban opened 7 years ago

turban commented 7 years ago

Thanks for providing this dataset! We've previously used MapQuest for our project, but it's discontinued as a free service, and we're now looking at Stamen Terrain as an alternative.

Many of our users are in Africa, and I've tested looked at the map tiles for Sierra Leone, and have a some questions:

screen shot 2016-07-25 at 15 27 32

  1. Large parts of the country look blurry. What is the reason (artistic, gradual change) for having this blurriness or fading between colors? What does the different shades of green mean?
  2. I see that the capital of Sierra Leone, Freetown, is missing for all zoom levels. There are also just four place names (three towns and a mountain) for several zoom levels. Do you plan to add more place names? If I compare with the US for the same zoom levels, there are many more place names.

screen shot 2016-07-25 at 15 41 27

  1. What are the blue-greyish areas along the coast? I interpret them as sumps as the color is waterish as the ocean - but is it the meaning or is it just showing low altitude?

Looking forward to use this new map :-)

almccon commented 7 years ago

Hi @turban, thanks for the bug reports! I'm not sure why there aren't many cities showing up in this country. I created issue #90 to track that. It also helped us discover that some capital cities for West Africa are missing in the source data we're using (which is a hand-curated list of city locations and zoom levels, not OSM-derived). I haven't completely figured out the problem, but we'll keep looking into it.

As for the colors and the blurriness, those colors are mostly landcover sourced from the 500m resolution MODIS data, with some OSM landcover added on top, where available. The colors and landcover types are defined here: https://github.com/stamen/terrain-classic/blob/master/landcover/LCType_z9.vrt#L8-L23, and I think this documentation is relatively up to date: https://github.com/stamen/terrain-classic/blob/master/landcover/landcover-palette.md. The OSM-derived landcover colors are mostly defined here: https://github.com/stamen/terrain-classic/blob/master/map.mss#L301-L401

Note that the colors are not hypsometric tints and do not correspond to elevation. Elevation is only indicated approximately via the hillshade. So the blue-gray areas along the coast are probably wetlands.

We had to add a blur effect to the landcover because the 500m resolution starts to look pixelated really quickly. If OSM landcover exists for an area, that data will take precedence, so if the MODIS landcover ever looks "wrong", you can fix it by adding OSM landcover polygons in that area. (However, we will not be updating the data from OSM very often, so it might take a while for OSM improvements to be reflected in this map).