How to set correct image dimensions by LatLngBounds using ImageOverlay? - leaflet

Question

I want to use ImageOverlays as markers, because I want the images to scale with zoom. Markers icons always resize to keep their size the same when you zoom.
My problem is that I can't figure out how to transform pixels to cords, so my image isn't stretched.
For instance, I decided my south-west LatLng to be [50, 50]. My image dimensions are 24px/24px.
How do I calculate the north-east LatLng based on the image pixels?

Answer 1

You are probably looking for map conversion methods.
In particular, you could use:
latLngToContainerPoint: Given a geographical coordinate, returns the corresponding pixel coordinate relative to the map container.
containerPointToLatLng: Given a pixel coordinate relative to the map container, returns the corresponding geographical coordinate (for the current zoom level).
// 1) Convert LatLng into container pixel position.
var originPoint = map.latLngToContainerPoint(originLatLng);
// 2) Add the image pixel dimensions.
// Positive x to go right (East).
// Negative y to go up (North).
var nextCornerPoint = originPoint.add({x: 24, y: -24});
// 3) Convert back into LatLng.
var nextCornerLatLng = map.containerPointToLatLng(nextCornerPoint);
var imageOverlay = L.imageOverlay(
'path/to/image',
[originLatLng, nextCornerLatLng]
).addTo(map);
Demo: http://playground-leaflet.rhcloud.com/tehi/1/edit?html,output