The question posted below
how to rotate a google map in a web application
can be use to rotate the map by rotating the div which contains the map
but if i do scroll or drag on the map the map is working in unpredictably way is there a way to retain those functionalities as it is
Note: i am rotating the map using div because the aerial tiles are not available at that location.
Please say whether this can be done with some other map api are how to go about it in google map API
It is difficult to answer with certainty unless you post a more complete answer, but I believe your issue is with the corrodinate system.
You are rotating the display of the map, but the x,y coordinates of your mouse are not. When you drag the mouse, the javascript is capturing the mouse movement relative to the screen and then you are rotating the output by 45 degrees. In other words, google maps has no idea that you have rotated it. It would be the same output if you just turned your monitor 90degrees, the mouse is still going to send the same x,y coordinates.
In order to do what I think you want you would need to take over the code handling the movement or accomplish it another way. You will notice that the dragging is disabled on the example you referenced.
This might be a place to start looking for getting the center of the map on mouse events:
https://developers.google.com/maps/documentation/javascript/3.exp/reference#MouseEvent
You might be able to get the current coordinates and "transform" the new coordiantes by looking at this example of getting pixels:
https://developers.google.com/maps/documentation/javascript/examples/map-coordinates
Here is a page explaining some things about transforming coordinate systems:
http://www.continuummechanics.org/cm/coordxforms.html
If this is something that you really have to do, it can probably be done, but it is likely a lot more trouble to get right than it is worth for an average map embed. It might also add a lot of processing that will make the interaction pretty laggy.
After saying all that, I'd still love to see an example of this working so if you do make it work please post some code.
Related
First, I have been reviewing some of the different Google Maps API docs, but I've never done much coding with it. I'm trying to build a simple game for kids in which, if the user clicks on a map within a certain distance of a key map point (could be within 1 mile, 100 yards, 5 miles...depending on situation), then the map point becomes visible and a custom message is displayed with it.
Which google maps api calls would enable this to work? How would I embed a hidden point on the map? With the map being rendered on the client, for security, if I could detect the point clicked and send that point via ajax to the server, then the server could send back whether there is a hidden point at that location, that seems like it could work. Or maybe there's a better way.
Can someone point me in the right direction, as to which API calls, and maybe code samples if possible? To summarize, I'm looking for the following functionality:
Track the lat/long coords of any user-clicked point on a google map. Have that click send the coords to my javascript function.
Have hidden points on the map that the user can't see, but either Maps (or at least just my server via ajax) can be aware of.
Ability to display a custom message right next to the clicked spot or hidden point, when needed.
Thanks!
When I understand correctly what you are trying to achieve it's much easier.
Draw a circle and hide the circle by setting the strokeWeight and fillOpacity to 0 . As radius use the allowed distance, as center the LatLng of the point
Although the circle now is not visible, the API will still respond to click-events on the circle, you only have to set a click-listener for the circle and create e.g. a marker at the center of the circle.
Note: a clickable circle will have a different cursor, you must set a unique cursor for the complete map, otherwise the users will be able to find the circle by hovering the map.
Demo: http://jsfiddle.net/doktormolle/0secbwuf/
I need to select an rectangular area on a map and identify markers that fall within that area.
Ideally, rectangle should be draggable and resizeable.
I am not too particular about the mapping and Google or Mapbox or Leaflet would all work just fine.
I found location-filter for Leaflet (https://github.com/kajic/leaflet-locationfilter/), which does seem to do the job. However, I couldn't find simple example code that shows how to use it. It has been used on tripcode.com but it is hard to make anything out of what is going on.
Does anyone have any experience with location-filter? If so, can you please point me to simple example of how to use it?
Are there similar examples for other mapping services particularly google maps?
Thanks.
For my bbox page I've snatched two files: SimpleShape, Rectangle from Leaflet.draw plugin and fixed them for better usability. The code for the rectangle is simple:
var rect = L.rectangle([[59.9, 29.9], [60.1, 30.1]]);
map.addLayer(rect);
rect.editing.enable();
rect.on('edit', function() { console.log(rect.getBounds().getBBoxString()); });
For advanced things like centering the rectangle on screen, see source code for the page.
When you are drawing the markers onto the map you will need to add them to some kind of an array which will contain the lat/lng pair of each marker.
You can use Leaflet.draw to draw the rectangle and modify it to return top left and bottom right coordinates on mouse up. On mouse up you can go over the entire list and which elements fit inside that bounding box.
This solution is just an example, there are many ways you can do this.
im totally new to this, and I need some help.
I need to create an aviation range map. Look at the below link, and in the menu to the left theres a "Range maps".
I started with the Google Maps API Javascript V3, I thought it could be a good base to get rid of Flash.
Now I need some pointers for how I can either add an object to the map or just click in the map and that brings up a circle around the pointer with range for how far the aircraft can go.
I sure hope you understand, and can give me some pointers for how to start. Every tip is appreciated!
http://www.cessna.com/citation/citation-cj4/citation-cj4-performance.html
Sounds like you want a Circle overlay, which is pretty easy to make. The docs have easy examples to follow.
You'll also want an onclick event for each overlay and for the map itself. That way whenever someone clicks on the map or on an overlay, it creates your circle. Check out the events documentation.
When clicking from one marker to another in Google Maps, the map screen animates the move smoothly if both markers are within them initial map view but jumps if one of the markers is off screen.
I'm trying to set up a map which has several locations within the main map area but has one which is 'off screen'. I have a signpost icon to the more distant location within the initial map area which I want to smoothly scroll to the off screen location when clicked (so as to give a better sense of it's relative location). I can't find anything in the Maps API which would let me do this however.
I could zoom out, move and then zoom in again but this looks a bit jarring. Am I missing something in the API, or does anyone have any suggestions?
Unfortunately, I don't think this is possible (without a change from Google). From the v3 API reference for panTo:
Changes the center of the map to the given LatLng. If the change is less than both the width and height of the map, the transition will be smoothly animated.
which implies that if that change is not less than the dimensions of the map, the transition won't be smoothly animated. The other pan methods are similar.
You could try moving in multiple steps but that's a bit of a hack and I suspect the result will be poor.
Sorry that's not very helpful (I have the same problem).
For me this method works, but i'm using Google Maps API v2.
LatLng latLng = new LatLng(lat,lng);
map.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, ZOOM_FACTOR));
This animates the camera from current position to the new one.
If you are using Gmaps API V2, then you can implement smooth animated move very easily by using panBy() method. You have to use fromLatLngToContainerPixel() method to find the amount of pixels to pan by.
Here is the bit of code:
var newLoc = map.fromLatLngToContainerPixel(new GLatLng(lat, lng));
map.panBy(new GSize( newLoc.x, newLoc.y ));
However, what I am trying to do is to achieve the same thing in maps API V3, but sadly fromLatLngToContainerPixel() method does not work anymore the way it did :(
I have a web application that needs to display 30,000 markers on a map at the same time. I don't want to use any kind of clustering. I need them to all be displayed.
I also need them to be clickable. The user can click on each point and a popup will come up with information about that point. Even at a low zoom level when there are thousands of markers in a single 256x256 square, the user needs to be able to click on them. It may be cumbersome for the user to click on a point thats bunched up with hundreds of other points, but if there happens to be one marker in the middle of nowhere, I want the user to be able to click on it right there instead of having to zoom in.
How do I do this? I know it's possible because I watched a video on google video where this guy creates a GTileLayerOverlay app that had clickable markers. He didn't explain how it was done though.
Is my only option to just remove the GTileLayerOverlay at high zoom levels and replace it with a true GMarker layer? I really don't want to do that. It seems over engineering to me.
If you were me, how would you go about this?
I found this example is in the Google Maps API Demo Gallery:
Clickable Tile Layer
This example creates a custom map type (GMapType) that shows regional borders and squares for county centers. When the squares are clicked, an info window opens with information about that county. The clickability is accomplished by passing in information about clickable pixel bounds in the cookies attached to the tiles, and doing a client-side check on mouseover for whether the mouse position was within the pixel bounds.
Here's some commentary on his method.
I don't have any experience with GTileLayOverlays, but I believe it is possible to accomplish what you're trying to do without using GMarkers.
Would it be possible to utilize clustering if each cluster could bring up a list of the markers it represents? It seems like having 30,000 markers visible at once would be visually confusing and difficult to navigate .