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4

Your assumption is right, you need the correct values for the corner coordinates. Since the source image is slightly larger than the Earth, you can not simply reproject the corner coordinates. You may use a different approach: According to the project site, the 5500x5500pix data is providing a 2km resolution on the center. So the extent from the center is ...


-1

use --with-static-proj when compiling gdal libraries.


0

Unfortunately, your test example is not online anymore, so I took a gobal Land-Sea-Temperature sample from ftp://landsaf.ipma.pt/pub/Example_of_Product/ As mentioned in my answer to Transforming geostationary satellite image to lon/lat, the size of global geos reprojected files is 3712x3712 pixels (3-km-resolution), but the actual data array is smaller. ...


0

The UTM 23S grid aligns with a degree grid only on the center longitude -45°. Other X and Y lines get bended (not only rotated) against a degree grid: The oblique mercator projection is rotated against true north in the center point. The mathematical formula rotates the local grid against the UTM grid, which does not align with true north in the center ...


2

You are right that the +datum=nad27 overrides the +towgs84 parameters, but only in that part of the world that is covered by the nad27 transformation grid. El Salvador is one of the countries in Central America, that has adopted the North American Datum, but is not covered by the grid. You can load the conus file used for the NAD27 transformation (located ...


2

You can see a demo in action to illustrate. The thing to keep in mind are: load Proj4js library and the local EPSG code proj4js declaration from http://epsg.io website get the ol.proj.projection object and set it extent (for managing map resolution) var extent = ol.proj.transformExtent([-8.74, 49.81, 1.84, 60.9], 'EPSG:4326', 'EPSG:27700'); var ...


2

I usually use a function to create WMS Layers to avoid redundances. function Tile(options){ return new ol.layer.Tile({ name: options.name || 'Layer', visible: options.visible === false ? false : true, source: new ol.source.TileWMS({ crossOrigin: 'anonymous', url: options.url, params: { ...


3

UPDATE: The above-mentioned approach by Oscar Perpiñán found here seems to work, if I only take a subset of the matrix the way Oscar did. For that to work I needed to know the subset boundaries and the static files, both available online for a few regions (such as North Africa). m = m[700:1850, 1240:3450, drop = FALSE] lon = raster("NAFR_LON.img") lat ...


1

Try loading proj4 before OL3. I had issues until I was told to load them in that order.


7

Your attempt is designed to fail. If you look at the image, you see the data arranged as a circle, with black triangles in the corners of the square, where the satellite view goes right into orbit. In your test data, you see only NODATA -32768 for those parts of the image. The extent is between +/-75 and +/- 78, but these values are only reached in the ...


1

latest versions of ol3 support client reprojection for both raster and vector data. even for tile layers. example here and here I think your fault is that you use the projection config on map and not on view. The rest of our code seems to be correct. Try this var view = new ol.View({ center: birmingham, projection:projection, zoom: 6 ...


2

You don't need to reproject a WMS layer, OpenLayers should make the request in the map projection for you automatically. The only time there might be an issue is if the WMS Server doesn't support the projection of your map, but checking the capabilities of your server shows that the layers are available in 3 CRS: <CRS>EPSG:25830</CRS> ...



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