I have a leaflet map consisting of a satellite image with lat-long metadata. My objective is to display a rectangle highlighting the selected tile on mouseclick and fetch the corresponding tile. The L.rectangle method needs bounds to display the rectangle. In order to calculate the SE and NW corners, I use the following function that I found at https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Tile_numbers_to_lon..2Flat.
This is for SE and the same function is changed for getting NW as seen in the above link. These are used as bounds for the rectangle.
//I have a fixed zoom level for my problem :4
function(xtile,ytile,zoom) //here i am giving the tile location coordinates as the input
{
n=2.0**zoom;
lon= (xtile+1)/n*360-180;
lat_rad=Math.atan(Math.Sinh(Math.PI*(1-2*(ytile+1)/n)));
lat=lat_rad(180/Math.PI);
return[-lat,lon]
}
The output comes out to be as follows:
NW -782.67,-112.4
SE -79.163,-89.9
with(suppose) xtile=5 and ytile=14
The actual output however should have been:
NW -66.51,-45
SE -74.01,-22.5
and the corresponding(again,suppose) xtile=5 and ytile=1
So basically, for some tiles , the rectangle shows just fine. But for others, it jumps to some other tile. I have a display window for the selected tileand when the rectangle jumps, neither the selected tile nor the highlighted tile is fetched. I will be really thankful is someone can help me with this.
My objective is to display a rectangle highlighting the selected tile on mouseclick and fetch the corresponding tile.
Then a good approach to the root problem is to use a custom L.GridLayer, since it provides functionality to create empty tiles, attach events to them and handle tile coordinates without the need to handle bounding boxes explicitly.
It would go like this:
L.GridLayer.ClickyLoad = L.GridLayer.extend({
// By default, the container for a whole zoom level worth of visible tiles
// has a "pointer-events: none" CSS property. Override this whenever a new
// level container is created. This is needed for pointer (mouse) interaction.
_onCreateLevel: function(level) {
level.el.style.pointerEvents = 'inherit';
},
// The tiles shall be empty <div>s with some DOM events attached.
createTile: function(coords){
var tile = L.DomUtil.create('div');
tile.style.border = '1px solid black';
// Highlighting the tile on mouse hover is just swag.
L.DomEvent.on(tile, 'mouseover', function(){
tile.style.border = '2px solid red';
});
L.DomEvent.on(tile, 'mouseout', function(){
tile.style.border = '1px solid black';
});
// When a tile is clicked, calculate the URL of the tile (using the same
// logic as L.TileLayer.getTileUrl() ), create a <img> element, and put
// the newly created image inside the empty <div> tile.
L.DomEvent.on(tile, 'click', function(){
var img = L.DomUtil.create('img');
img.src = L.Util.template('https://tile.openstreetmap.org/{z}/{x}/{y}.png', coords);
tile.appendChild(img);
});
return tile;
}
});
// Create instance and add to map
(new L.GridLayer.ClickyLoad()).addTo(map);
See a fully working example here.
As usual with this kind of non-trivial-looking examples, reading through the Leaflet documentation, the tutorial about extending classes, and the Leaflet source code itself is recommended.
Related
I am trying to add a hover effect to each speech bubble in the image below that link to a different page when clicked on.
Currently, I am using an image map and whenever an area of is hovered over jQuery changes the whole image to be the appropriate image that has the speech bubble filled in. It kind of works but IE flickers every time a hover happens and the website is responsive so the image map does not scale when the screen size is changed. I've tried using https://github.com/stowball/jQuery-rwdImageMaps too but it doesn't seem to work on a mobile device.
Ideally I'd like to be able to have the speech bubbles be separate images that are positioned correctly when scaled so I can manipulate the speech bubbles easier.
Screenshot
You could go with approach which uses scaled coordinates.
Here's the basic idea:
var coordManager = {
"imageBaseHeight":800,
"imageBaseWidth":800,
"imageID":"myImg",
"baseCoordinateActions" = [
{"x":10,"y":10,"h":100,"w":100, "text": "Mousing over first option"}, // the square you want the mouseover to cover for a given action
{"x":200,"y":200,"h":100,"w":100, "text": "Mousing over first option"}
],
"scaledCoordinateActions" : [], // this should contain the baseCoordinateActions with the scaled values
"init" : function(id, baseHeight, baseWidth)
{
var self=this;
this.imageID=id;
this.imageBaseHeight=baseHeight;
this.imageBaseWith=baseWidth;
var img = document.getElementById(id);
img.onresize =function()
{
// regenerate the scaled coordinates based on the difference between the imageBaseHeight and the current height;
// usually you can get the scale by dividing the imageBaseHeight by the actual height
};
image.onmousemove = function(event)
{
// check the mouse location based on scaled coordinates if it's within the scaled coordinates of any of the scaledCoordinateAction items
// display that scaleCoordinateAction item's text using the current eventX and Y, or do it relative to the coordinateACtion X and Y.
// make sure to check if the bubble is already showing before changing the display: property to avoid flicker.
}
}
};
coordManager.init("imageID", 800,800);
I have two layers one on another top. First layers is background, second layer is flower. How I can know on what layer clicked.
If I clicked on background result it's good return first layer place where clicked:
If I clicked on flower result it's good return second layer place where clicked:
If I clicked on background near flower result it's bad return second layer place where clicked:
3.1 I get second layer because actually image is bigger, because image have transparent place:
For test use JSFiddle: http://jsfiddle.net/sbkhtvmo/1/
You could try creating a transparent SVG path layer that covers the flower and make that the flower click layer, then make everything else the background click layer.
Use clientX and clientY to get the position of the mouse in the window.You can also do that with jQuery offset to get the position.
jQuery example that I found useful on stackoverflow:
$(document).ready(function() {
$('imageElement').click(function(e) {
var offset = $(this).offset();
alert(e.clientX - offset.left);
alert(e.clientY - offset.top);
});
});
I'm trying to make an interactive floor plan. When the user hovers a room I want to display some sort of message.
All my floor-plans are in JPEG format.
I would like to make something like this: http://dciarletta.github.io/d3-floorplan but I need to also make a tool in the backend that would create those overlays.
My questions is, how can I do it? Ideally I would just click around the room to create the overlay, but I don't think d3.js allows it. I'm also having a problem getting the correct coordinates:
$('#floor').click(function(e) {
var $this = $(this);
var offset = $this.offset();
var pos = [];
pos.x=(e.pageX-offset.left);
pos.y=(e.pageY-offset.top);
console.log('x: '+pos.x+' | y: '+pos.y);
});
http://jsfiddle.net/5nTEk/
So, not only I don't think I'm getting the correct coordinates as I don't know how to add an overlay as the link above... Any suggestions?
You can probably do it by overlaying an SVG over your <img>. D3 would render into this svg panel. You can create a polygon in the SVG based on the user clicks.
If you use the d3.event mouse locations (mouseX and mouseY, I think), you can get click positions relative to the SVG element, and then use those as vertex locations on a polygon. Checking for click proximity to the original point will allow you to decide when to close the polygon.
Ok, here is my problem, I'll put a picture to illustrate it easier.
I need the user to draw some polygons, representing the coverage area.
The polygon needs to have fixed number of points (vertex) because it goes into a processing algorithm later, and it would be really slow if a polygon can contain a lot of points.
Anyway, in my example lets stick to hexagons (6 points).
The user need to be able to drag the polygon around and modify it, but not change the number of points.
I tried setting the editable: true option for the polygon, it works fine, but it gives me the situation shown on the picture. It creates a handle for every point, and another handle (semi-transparent) in the middle between each points. Now, if the user moves that semi-transparent point, it will add another point (vertex) to the polygon, and add additional two handles in the middle of newly created lines. That gives us a 7 point polygon.
The best option would be to remove those semi-transparent handles, so the user can only drag polygon points, and it that way he can't affect the total number of points.
Can I achieve this using google maps editable option?
Another way to achieve what you want is to forego the built-in edit-ability of the polygon and implement it yourself. This is more powerful and flexible.
First, don't make the polygon editable. Next, make a Marker for each corner of the polygon. Finally, make each marker draggable and an event listener on it's "drag" event to update the polygon.
Making the markers and adding the event listener:
for (var i=0; i<coordinates.length; i++){
marker_options.position = coordinates[i];
var point = new google.maps.Marker(marker_options);
google.maps.event.addListener(point, "drag", update_polygon_closure(polygon, i));
}
Where update_polygon_closure is defined as:
function update_polygon_closure(polygon, i){
return function(event){
polygon.getPath().setAt(i, event.latLng);
}
}
Full code is in a jsfiddle here: https://jsfiddle.net/3L140cg3/16/
Since no one seems to have a better solution, I'm marking my workaround as accepted, in case someone stumbles upon the same problem. Not very pretty, but gets the job done
The only solution I found so far is to hide the handles manually after the polygon has been drawn. The problem here is that the handles don't have any CSS class or id, so I have to hide all divs with opacity 0.5 (opacity of the handles). It works, but it is pretty risky, considering that something else might have the same opacity and doesn't need to be hidden.
// variables
var map, path, color;
polygon = new google.maps.Polygon({
paths: path,
strokeColor: color,
strokeOpacity: 0.8,
strokeWeight: 2,
fillColor: color,
fillOpacity: 0.10,
editable: true,
});
polygon.setMap(map);
setTimeout(function(){ map.find('div[style*=opacity: 0.5]').hide(); }, 50);
As a slight improvement to #zolakt's answer, you can both hide the midpoint divs on the polygon and add a mousedown event listener to track when a midpoint is clicked to prevent dragging and changing the polygon:
// hide the midpoints (note that users can still click where the hidden midpoint
// divs are and drag to edit the polygon
$('#multi_markers div[style*="opacity: 0.5"]').hide();
// get the paths for the current polygon
var octopusPaths = HotelLib.octopusPolygon.getPaths();
// track when a polygon midpoint is clicked on
google.maps.event.addListener(HotelLib.octopusPolygon, 'mousedown', function(mdEvent) {
// if a midpoint is clicked on, mdEvent.edge will have an integer value
if(mdEvent.edge || (mdEvent.edge == 0)){
// immediately reset the polygon to its former paths
// effectively disabling the drag to edit functionality
HotelLib.octopusPolygon.setPaths(octopusPaths);
// hide the midpoints again since re-setting the polygon paths
// will show the midpoints
$('#multi_markers div[style*="opacity: 0.5"]').hide();
}
});
I just created an alternative solution to this without having to fiddle around with setTimeout or the polyline creation. This is also a somewhat global solution, so you can basically drop it in any established program that uses Google Maps.
We'll use MutationObserver to observe when those midpoint nodes appear on the DOM and then instantly hide them. They should start appearing when something is set as editable.
Basically just put this anywhere after the map is initialized:
var editMidpointNodeObserver = new MutationObserver(function(list, observer)
{
if($('#mapwrapper div[style*="opacity: 0.5"]').parent('div[style*="cursor: pointer"]').length > 0)
{
$('#mapwrapper div[style*="opacity: 0.5"]').parent('div[style*="cursor: pointer"]').remove();
}
});
editMidpointNodeObserver.observe($('#mapwrapper')[0], { childList: true, subtree: true });
Change the #mapwrapper to whatever the id of your Google Maps wrapper element is. I am using jQuery here, so therefore the $('#mapwrapper')[0] to convert jQuery object to a native DOM object. Should work without jQuery as well, I am assuming you know how to convert this to vanilla js.
We also just straight up remove the nodes, so no need to worry about user being able to click invisible ones by accident or otherwise.
MutationObserver should be supported in all browsers: https://caniuse.com/mutationobserver
Link: http://www1.qhoach.com/
When you drag, this map is panned... But if you drag on KML features (icon with circle), nothing happens
First of all,in your application there are four level of maps including the vector layer you mentioned with circle icons in your question.
0: "Đường Sá" ||---> Overlay Tiles
1: "Vệ Tinh" ||---> Overlay Tiles
2: "TMS Overlay" ||---> Markers ~ Icons
3: "KML" ||---> Vector
Analysis:
Starting with zero to last one,only vector seems to be the last one,others stays as overlay tiles.In order to come this problem we have to focus on marker layer,namely features (icons).
As you have seen on map,click event for map has been triggered when you try to drag the map around.You can't drag because event registration is working for marker layer first not for the map.That means in order to drag the map,moving mouse(drag) after click must follow.Since you're trying this on vector layer,there is no chance to pass the event to overlay layers.
Solution:
I propose you two ways to achieve this bug-type problem.
Let this be the long way
There is a control in OpenLayers known as SelectFeature inherited from Handler.Feature.This control generally allows vector feature from a given layer on click on hover.Which means this handler can respond to mouse event related to any drawn features.Only callbacks are associated with features,needing one of them click.Now all we have to do is to fall click event back to as we pan for overlay tiles.
var selectFeat = new OpenLayers.Control.SelectFeature(
vector, {toggle: true, clickout:false});
selectFeat.handlers['feature'].stopDown = false;
selectFeat.handlers['feature'].stopUp = false;
map.addControl(selectFeat);//instance of map
selectFeat.activate();
Once this control is activated you have to ensure your layers to pass events through another layer.To do that,simply
layer.events.fallThrough = true;//both for vector and marker layers
After all these actions we made so far,one last thing left to do:
That's switching the order of markers and kml layer.
And this should be the easiest way
That's z-index on layers.You can check in above sequence of layers that the layer which has highest id has also highest z-index.
layer.setZIndex(...any number...);
In addition to this solution,easy way allows only you to drag through map,when all sudden clicking features of icons may lost without long way,so it's your choice to leave them behind.
Mouse events do not want to propagate through an svg Vector overlay to layers underneath.
The solution above demands all marker HTML layers have higher zindex than all Vector SVG layers.
The following CSS provides a potential/partial work-around, propagating events through the svg element, but only where there is no vector elements within the svg overlay:
/** Hack so mouse events propagate(bubble) through svg elements, but not the
images within svg */
.olLayerDiv svg {
pointer-events: none;
}
.olLayerDiv svg * {
pointer-events: auto;
}
Combine the above CSS while adding fallThrough:true to all OpenLayers events objects within maps, layers, and controls.
// map events
var map = new OpenLayers.Map(div, { fallThrough:true } );
// layer events
var lvec = new OpenLayers.Layer.Vector( .... );
lvec.events.fallThrough = true
map.addLayers([lvec])
// all map controls
var ctrl = new OpenLayers.Control.SelectFeature( lvec, {...
fallThrough: true, autoActivate:true });
map.addControl( ctrl )