Projection

  • Projection translates between screen locations (in pixels) and geographic coordinates (LatLng) on a map.

  • It provides methods to convert screen points to LatLng and vice versa.

  • Projection allows access to the visible region of the map, useful for determining the geographic bounds currently displayed.

  • Screen coordinates are relative to the top-left corner of the map, not necessarily the entire screen.
public final class Projection extends Object

A projection is used to translate between on screen location and geographic coordinates on the surface of the Earth (LatLng). Screen location is in screen pixels (not display pixels) with respect to the top left corner of the map (and not necessarily of the whole screen).

Public Method Summary

LatLng
fromScreenLocation(Point point)
Returns the geographic location that corresponds to a screen location.
VisibleRegion
getVisibleRegion()
Gets a projection of the viewing frustum for converting between screen coordinates and geo-latitude/longitude coordinates.
Point
toScreenLocation(LatLng location)
Returns a screen location that corresponds to a geographical coordinate (LatLng).

Inherited Method Summary

Public Methods

public LatLng fromScreenLocation (Point point)

Returns the geographic location that corresponds to a screen location. The screen location is specified in screen pixels (not display pixels) relative to the top left of the map (not the top left of the whole screen).

Parameters
point A Point on the screen in screen pixels. Must not be null.
Returns
  • The LatLng corresponding to the point on the screen, or null if the ray through the given screen point does not intersect the ground plane (this might be the case if the map is heavily tilted).

public VisibleRegion getVisibleRegion ()

Gets a projection of the viewing frustum for converting between screen coordinates and geo-latitude/longitude coordinates.

Returns
  • The projection of the viewing frustum in its current state.

public Point toScreenLocation (LatLng location)

Returns a screen location that corresponds to a geographical coordinate (LatLng). The screen location is in screen pixels (not display pixels) relative to the top left of the map (not of the whole screen).

Parameters
location A LatLng on the map to convert to a screen location. Must not be null.
Returns
  • A Point representing the screen location in screen pixels.