##
Sliders

Sliders can be used for continuous numeric input. In this example, all possible parameters for each projection can be changed
. These are:

- central longitude
- central latitude
- latitude of true scale
- first and second longitude
- fist and second latitude

Every projection supports only a subset of these parameters. Many of them can only change the central longitude, e.g. the sinusoidal
. The Transverse Cylindrical Equal Area projection
can change both its central longitude and latitude, e.g. to center the world around Africa
. All conic projections, e.g. the Alberts Equal Area
can set these two
, but they also have to set the first and second latitude, at which the projection cone slices the globe
. An interesting projections is the Two Points Equidistant, for which two base points have to be specified. All distances from every point on the map to each of these two points are correct
. Finally, the Bonne projection
is an elegant 18th century projection, that can be made to show some very surprising world views
.