[Bug] Zoom relative to cursor position isn't consistent

[iarwain]

Hi,

From what I've noticed, there are two issues at hand:

• it seems zooming in will take into account the cursor's position but not zooming out. For example, keeping the cursor in a corner and repetitively zooming in and out will progressively shift the content of the screen over time.
• the second one is more minor: when zooming in, the transition isn't smooth, ie. the point under the cursor doesn't remain static during the transition as if the zoom happens first and the translation to keep the cursor's position static in the "world" happens next, resulting in a jerky motion

Expected behavior:

When zooming in and out, the "world" point under the cursor should remains under the cursor at all time, during transition and during zoom in/zoom out. For reference, one can try zooming in/out on Google Maps or similar.