By default, zooming in or out zooms using the mouse's location
as an anchor, which makes it possible to navigate the map
using scrolling only, and makes zooming in more intuitive.
This commit adds a new useAnchor option to the MouseWheelZoom
interaction. It is enabled by default, which changes nothing
to the current behavior of the interaction. When disabled,
the interaction stops registering its lastAnchor_ value. This
turns the zoom into a very basic one, that zooms to the center
of the screen.
To use the map center zoom, set the useAnchor option to
false when creating the MouseWheelZoomInteraction, or use its
setMouseAnchor function.
This commit allows setting a z-index property on the layers and uses
it in the canvas, WEBGL and DOM map renderers for ordering the layers
before rendering.
Default z-index is 0 for managed layers and 1000 for unmanaged ones.
It allows always on bottom, always on top and more complex layer layouts.
This allows features to be moved around the map. It works much like the Modify interaction, however it's significantly simpler. It uses the geometry's underlying `translate` function.
Where workers are not available, or if operations are trivial to run, the main UI thread can be used instead. This also adds tests that run in real browsers.
Fit accepts either a geometry or an extent.
This combines two previously distinct functions
into one more flexible call.
Also brings the rotations support and options
previously available to fitGeometry to extents
Using the term 'bottom-left' for origin and origins is misleading, because
many developers use -y-1 for the tile url's y in their tile url functions,
and the origin really only determines where tile coordinates start to
increase from left to right and from bottom to top.
By adding a getTileCoordForTileUrlFuction method like for ol.source.Tile,
we can now properly handle extent and resolution restrictions, and reuse
tiles on wrapped worlds. Also adds the missing wrapX option to
ol.source.TileVector.
