In MapBox GL JS, when I call queryRenderedFeatures or querySourceFeatures, it returns an array of features with geometries. Using a vector tile source, the feature geometry objects have coordinates like (-154.34, 80.99) for a location near the lat/lon (-77.37, 38.98). In what projection are the coordinates? And is there a way to convert them to WGS84?
It turns out, this is a MapBox bug. I added a bug report here: https://github.com/mapbox/mapbox-gl-js/issues/4011.
The geometry objects are supposed to have GeoJson lat/lons.
Related
It`s necessary to make tiles in the non-mercator projection to display them in Leaflet using the Proj4Leaflet library.
How can i do this?
I tried to do it in Qgis, but the result was negative.
I'm trying out Mapbox for the first time, and playing around with drawing some polygons in the dataset editor for export to a tileset. However, the polygons in the resulting tileset are not the same as what I create in the editor. The polygons are only very rough, simplified approximations of the originals.
In dataset editor:
In map layer as tileset export:
I understand that Mapbox does vector simplification at certain zoom levels, but these changes are not zoom-dependent. I zoom in all the way and the shapes are still like this.
Moreover, such extreme degredation of the geometries makes tilesets essentially useless for features that require any sort of accuracy, like property lot lines.
Am I missing something, or is this really the expected behavior? Is there really no way to get accurate geometries into a tileset?
UPDATE: It appears this is only happening with shapes I create by drawing in the Mapbox data editor. So far the geometries that I've uploaded as geojson files have gotten converted to tilesets accurately...
I suspect this is because the maxzoom is too low.
When you create a Mapbox Tileset, either by uploading GeoJSON directly as a new Tileset, or by exporting your your Dataset to a Tileset, Mapbox will try to guess an appropriate minzoom and maxzoom of the Tileset.
Sometimes the min/max zoom's used aren't suitable for the map you're trying to create. Since there is no way to specify a maxzoom in either of the two approaches the only alternative is to create your Tileset locally with https://github.com/mapbox/tippecanoe specifying an appropriate maxzoom for your data and then uploading the resulting .mbtiles as a Mapbox Tileset.
Is there a way to draw a vector layer with CorelDraw for example and place it on napboxgl and use it as geojson layers?
For example https://seatgeek.com/colorado-rapids-at-seattle-sounders-fc-tickets/mls/2017-10-22-1-pm/3700786
Are they using geojson or etc.? Or just some sort of vector format?
I can't use geojson as it is hard to draw with QGIS any straight lines or symmetrical objects. I just want to draw a lot of vector objects and use them as layers with mapboxGL(use mapbox as render method and interact with layers as with geojson)
Any suggestions how to do it? Or is there a way to draw with Corel and then place it on map with QGIS?
Thanks
UPD:
Now I am using Corel -> dxf export and then import it to QGIS, then save it as geojson. But have some glitches with displaying that geojson geometry in mapbox, so I have to draw another in QGIS over the imported(dxf) one.
Here is an example of the bug, should be just a green polygon like the gray one
UPDATE: my fault, I was using lines instead of polygons.
I think you can achieve this as follows:
Convert the Corel output to SVG
Create an HTML element containing the SVG (not necessarily added to DOM)
On your Mapbox map, add a Canvas source containing the canvas: see https://www.mapbox.com/mapbox-gl-js/api/#canvassource
Obviously you will need to determine the lat/lon of the corners of your image somehow.
I'm using Mapbox GL JS to display a map using my own tile-server (which just serves openmaptiles pbf files in a Z/X/Y directory structure).
The loading of tiles is done automatically, based on the current center coordinates.
I want to pre-load the surrounding tiles for an offline solution.
I know how to get the current zoom-level with map.getZoom()
How can I get the X and Y indexes of the current tile URL ?
I suggest framing the problem in terms of geographic coordinates:
You can get the viewport geographic coordinates from Map#getBounds)
You can convert geographic coordinates to tile coordinates with some light math
Also, if you need to do some calculations in bash scripts, you can use mercantile library or CLI utility to transform lon/lan coordinates to tiles, find parent or children tiles and get some other information. Another advanced tool is supermercado.
I'm trying to use a Mapbox style in my map. The style loads fine, but it seems to be way off. My GeoJson file should load points in California, and it works fine with other tilesets, but using the Mapbox dataset it loads somewhere north of Canada in the arctic circle. This seems like it's probably a problem with projections. The GeoJson file is in WGS84, which I believe is the Geojson default. The setview centers the view on the US using other tilesets but also centers the data north of Canada using Mapbox data. Here's the bit where I include the Mapbox data
L.mapbox.accessToken = 'correct token';
var map = L.mapbox.map('map')
.setView([43.64701, -79.39425], 4);
L.mapbox.styleLayer('mapbox://styles/mapbox/light-v9').addTo(map);
Leaflet uses LatLng rather than mapbox's LngLat. Do you want your data to be around [43.64701, -79.39425], or around [-79.39425, 43.64701]?
See also Tom MacWright's explanation on why some libraries/formats use lat-lng and some use lng-lat.