3 Virginia layers

[stoecker]

The 3 Virginia layers use a tileify service instead of the direct WMS.

These should be changed to use WMS directly and add the TMS as mirror only (using https which is supported now).

[stoecker]

Hmm, seems that is more complicated. Klumbumbus: Can you tell me what you know about this. Why can't we use the direct service?

[Klumbumbus]

The direct wms was not working as the zoom parameter was strange. See ​https://github.com/osmlab/editor-layer-index/pull/540#issuecomment-415564776 and following comments. If you get the direct wms working we can use it and move the tilefy urls into mirrors.

[stoecker]

JOSM has a somewhat more complex way for the zoom parameter than other software: You can add {zoom+12} or subtract {zoom-7} or even reverse {7-zoom} the value. But it still requires the the levels have same meaning, only with different numbering. If they aren't created by power of two starting with full world, then it wont work.

[Klumbumbus]

Replying to stoecker:

You can add {zoom+12} or subtract {zoom-7} or even reverse {7-zoom} the value.

Yes, I tried 2 or 3 of such "advanced parameters" but the ones I tried didn't work so I gave up searching for the right one...

[stoecker]

Replying to Klumbumbus:

The direct wms was not working as the zoom parameter was strange. See ​https://github.com/osmlab/editor-layer-index/pull/540#issuecomment-415564776 and following comments. If you get the direct wms working we can use it and move the tilefy urls into mirrors.

I did read that, but actually it did not help to reduce my confusion what exactly is correct and what this ArcGIS tileify does.

The code seems to request the images with EPSG:4326 coordinates and a &bbox= parameter: ​https://github.com/JasonSanford/tileify-ags/blob/master/index.js lines 45 and 46

That does not sound correct to me as well, as it ignores the 4326/3857 differences (like josm did in the past :-):

[stoecker]

Direction is positive:
​https://gismaps.vita.virginia.gov/arcgis/rest/services/VA_Base_layers/VA_Building_Footprints/MapServer/tile/7/6315/4620
→
​https://gismaps.vita.virginia.gov/arcgis/rest/services/VA_Base_layers/VA_Building_Footprints/MapServer/tile/8/12630/9241
is a zoom in.

[stoecker]

At zoom 12 the outlines start, which is zoom 19 for tileify:
​https://gismaps.vita.virginia.gov/arcgis/rest/services/VA_Base_layers/VA_Building_Footprints/MapServer/tile/12/202080/147856
​https://tileify-ags.herokuapp.com/tiles/19/145637/204489?url=https%3A%2F%2Fgismaps.vita.virginia.gov%2Farcgis%2Frest%2Fservices%2FVA_Base_layers%2FVA_Building_Footprints%2FMapServer&transparent=true&layers=show%3A20

That would mean {zoom-7}. Now the question is if x and y are also manipulated.

[stoecker]

AHHHHH. Reversed!

​https://tileify-ags.herokuapp.com/tiles/19/147856/202080?url=https%3A%2F%2Fgismaps.vita.virginia.gov%2Farcgis%2Frest%2Fservices%2FVA_Base_layers%2FVA_Building_Footprints%2FMapServer&transparent=true&layers=show%3A20

It is {zoom-7}/{y}/{x} if I'm not mistaken!

[Don-vip]

What's the status of this ticket?

[stoecker]

Replying to Don-vip:

What's the status of this ticket?

We could make direct URLs like ​https://gismaps.vita.virginia.gov/arcgis/rest/services/VA_Base_layers/VA_Building_Footprints/MapServer/tile/{zoom-7}/{y}/{x} and copy the other ones to mirror, but someone needs to verify that the images are really identical.

I found motorbiking and other tasks more interesting than JOSM lately due to the fine weather :-)

[stoecker]

Fix in Maps/USA version 121. Tiles looked identical, Building borders looked a bit different (different style and caching involved?).

[stoecker]

Hmm, Website preview wont work :-) Does anyone have an idea how "zoom-7" has to be done for OpenLayers?

[stoecker]

Ah seems, there is a function for specific tile urls like that.

​https://gis.stackexchange.com/questions/164162/openlayers-3-overlay-a-tms-layer-on-a-osm-layer

tileUrlFunction: function (coordinate) {

 if (coordinate === null) return undefined;

// TMS Style URL
 var z = coordinate[0];
 var x = coordinate[1];
 var y = coordinate[2];
 var url = 'https://quadridcmmaps.blob.core.windows.net/tynset/' + z + '/' + x + '/' + y + '.png';
 return url;
}

[stoecker]

Fixed display of {zoom-.} in preview.