Is there a way in Geoviews to always display only a small box / portion of the map rather than the whole world zoomed out? It seems to always begin such that the entire world is displayed. I was wondering if there is any option to choose the min/max latitude and min/max longitude?
If you display a WMTS element on its own it will default to a global view. You can however override that by setting the extents on the element, e.g.:
gv.WMTS(some_url, extents=(-70, 20, -50, 30))
The extents are defined a 4-tuple of the (left, bottom, right, top) edges. However if you overlay some actual data on top of a tile source it should automatically set the extents to the range of your data.
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I'am using reactJS and want to design a component with following functionality :
Display pixelated image which is able to zoom in and zoom out at pixel level.
When clicked on image , display a marker- which can be a dot or icon at specific position.
When image is zoomIn/zoomOut, marker size and position should not change.
Even after zoomIn/zoomOut when clicked on image, marker should get repositioned at proper pixel on the image.
I am thinking of applying same logic as used in the maps/ leaflet. Like they maintain separate layers for map and markers on the map. If we zoomIn/out maps it won't affect the marker position or size, same functionality I want for the image.
Anyone with the solution or related library will be welcomed !
(For reference, I want this design for marking GCP(Ground Control Points) on the image, which requires very precise marking at pixel level)
I have a Map that fills the window and some locations from which I generate a georectangle. I want to set the visibleRegion of the Map to the georectangle but I also want a margin (in pixels) a the bottom of the window for overlays, so that the locations are never hidden behind the overlays. How can I do this?
I have openlayers map with a polygon feature.
When we hover over the polygon, it displays the description in overlay.
However the overlay is always displayed on the polygon and not to left and right which is what I am trying to do. In doing so I juggled with css of overlay but couldn't come to the solution. There is leaflet bindPopup() method to display tooltip on objects added to map which I tried to understand but couldn't gain anything there.
My goal is to keep the overlay within the viewport of the map so that it would always be visible.
Just to illustrate what I am expecting here is the fiddle : leaflet popup
Current status : Openlayers overlay positioning
Just set the overlay to appear on the left of the extent of the polygon, such as:
if (feature && feature.get('type') == 'Polygon') {
var ext = feature.getGeometry().getExtent();
let coordinate = [ext[0], (ext[3]-ext[1])/2];
content.innerHTML = feature.get('desc');
popup.setPosition(coordinate);
}
Then you can play with the CSS to display the overlay the way you want.
I want to compare a raster I made against Google's satellite basemap. I produced a georeferenced coloured TIFF with appropriately placed nodata where it should have. I then tiled this using gdal2tiles. When I overlay my custom TIFF on Google sat. map it works fine but my custom map is surrounded by a gray background instead of a transparent one.
I believe it's because swipe replaces the two layers altogether. Is there a way to achieve what I want properly?
You are probably using leaflet-side-by-side plugin?
In that case, and if you need the same background tiles in both sides, a very simple trick is to add that background Tile Layer to the map, but not to L.control.sideBySide. You can leave the left side as an empty array for example.
var backgroundTiles = L.tileLayer(backgroundTilesUrl).addTo(map);
// Tiles with transparent background
var customTransparentTiles = L.tileLayer(customTilesUrl}).addTo(map);
L.control.sideBySide([], customTransparentTiles).addTo(map);
Demo: http://jsfiddle.net/ve2huzxw/149/
If you need a different background tile layer on the right side (under your custom transparent tiles), simply create a new Tile Layer instance and pass an array of layers as 2nd argument of L.control.sideBySide.
Note: for some reason the left Tile Layer must be added last to the map.
var backgroundTilesRight = L.tileLayer(backgroundTilesRightUrl).addTo(map);
var backgroundTilesLeft = L.tileLayer(backgroundTilesLeftUrl).addTo(map);
// Tiles with transparent background
var customTransparentTiles = L.tileLayer(customTilesUrl).addTo(map);
L.control.sideBySide(
backgroundTilesLeft,
[
backgroundTilesRight,
customTransparentTiles
]).addTo(map);
Demo: http://jsfiddle.net/ve2huzxw/150/
i'm using map.panTo() to have a nice smooth transition between the markers, when i click from a list of locations, but i can't see a similar methods for the zoom...I imagine something like setZoom(13, 1500) where 1500 is the duration...
any clue?
The only native function to zoom so far is map.setZoom which does not let you change the speed.
If you want to set your map to the zoom level based on a set of markers you can do something like this:
var bounds : LatLngBounds = new LatLngBounds(southwestmarker.getLatLng(), northeastmarker.getLatLng());
bounds.extend(someMarker.getLatLng());
//some more extend() here
map.setZoom(map.getBoundsZoomLevel(bounds));
I've found that the map.setZoom will smooth the transition if the zoom level is within 2 of the current zoom level.
So if the map is set to zoom of 10, and I set it to 12 it will transition. However if I set it to 13 it wouldn't.
Also you can set zoom to a non whole number but the map tiles will not load and state 'Sorry, we have no imagery here'.
You could try chaining zooms but I they ease in/out so it would look jerky.
If the transition is more than 2 and it's important to be smooth, you could manually edit the matrix transform on one of the map DOM elements. It looks like -webkit-transform: matrix(1, 0, 0, 1, -62, 71);. Changing the 1st and 4th numbers would affect the scale, the first is x-scale and 4th is y-scale.
The matrix is like so transform: matrix(xs, 0, 0, ys, xt, yt);, where xs and ys are the scale, setting it to 2 would zoom in 200%. This matrix does take fractional values, so you can zoom to 1.1 etc. You could then map.setZoom() to your final number at the end of the transition.
This does have some caveats as it's not the intended usage:
Panning or zooming while transitioning would break the matrix transformation by resetting it to Google's own methods.
Zooming out is harder because the surrounding tiles (beyond the viewport) aren't loaded - defaulting to a grey square. You could have a duplicate map with a viewport the size of your current map multiplied by the factor you're zooming out - so if you were zooming out so your map was half the size, then the viewport would be double. You could then place the viewport over the top and set the zoom on the 'real' map, transition the adjusted viewport map and hide it on completion.