map navigation
Widget gallery Zooming
Lens
Swiss precision: magnifying glass reveals an enlarged view.
The movable region around the mouse, the lens, transforms information below it through magnification, fisheye views, information filters, or graphics filters. In this example, dragging the mouse over the soil map of Switzerland, the lens displays a magnified and more detailed view of the underlying map, confined to the area around the mouse.
This widget makes use of JavaScript to change the visibility of a dynamic HTML layer that holds an image of a more detailed map of the same area. Users can switch this functionality on or off clicking the “Lupe aus/ein” button. The size of the region around the mouse can be modified by entering a custom value in the input field (“Lupengrösse in Pixel”).
Whereas the magnification lens only shows two levels of details of the same map, a fish eye lens shows the map at decreasing magnification factors with increasing distance from the mouse pointer, thus providing a smooth transition between both levels of detail. An information filter for instance shows street names on a map only within the region around the mouse. A graphics filter can apply a blurring or tinting transformation to the underlying map, useful for indicating the accuracy of the information, or for highlighting specific map features.