WMTS GetFeatureInfo in android

Question

I want to create something in android like this: http://openlayers.org/dev/examples/wmts-getfeatureinfo.html I'm able to load the custom tiles with WMTS but now I need to get data to show in some kind of a popup window when clicked (touched).

I found that you can get extra info with the service getFeatureInfo, for this request i need some extra parameters like "I" and "J".

Which are the number of pixels from the bottom-left point of the tile to the clicked position on the tile?

I have no idea how I can get these parameters in android.

Answer 1

For those who are still interested in the answer. I've calculated the pixel coordinates with the following formula:

int zoom = (int) mMap.getCameraPosition().zoom;

    double sinLatitude = Math.sin(ltln.latitude * Math.PI / 180);
    int pixelX = (int) (((ltln.longitude + 180) / 360) * 256 * (Math.pow(2,zoom)));
    int pixelY = (int) ((0.5 - Math.log((1 + sinLatitude)/ (1 - sinLatitude))/ (4 * Math.PI)) * 256 * (Math.pow(2, zoom)));

    // calculate pixel coordinates on tile
    int i = pixelX % 256;
    int j = pixelY % 256;

    // calculate x and y coordinate tile
    int x = pixelX / 256;
    int y = pixelY / 256;

Here you get the x and y coordinates from the clicked tile and the pixel coordinates of your marker on the tile.