mousewheel-zomm (in/out)

[greq]

with this enhancement it is possible to zoom in and out with the mousewheel in the mapframe (like GoogleMaps).

needed JQuery extension:

• Mouse Wheel Extension 3.0.0
  
  • (website: ​http://plugins.jquery.com/project/mousewheel)
  • (downloadlink: ​http://plugins.jquery.com/files/mousewheel_3.0.zip)

edited file(s):

• mapbender/http/php/mod_map1.php

short summary (main function: mousewheelZoom ()):

• local koordinates and mousewheel-deltas will be used to:
  
  1. zoom in/out to a point (with the functions: makeClickPos2RealWorldPos, zoom).
  2. map will be translatet, so that the mouse-cursor stays still at the same realworldcoordinate.