Projection

AI-generated Key Takeaways

• Projection is a class used to translate between on-screen locations in screen pixels relative to the top left of the map and geographic coordinates (LatLng) on the Earth's surface.

• The fromScreenLocation method returns the geographic location (LatLng) corresponding to a given screen location (Point).

• The getVisibleRegion method gets a projection of the viewing frustum for converting between screen coordinates and geographical coordinates.

• The toScreenLocation method returns a screen location (Point) that corresponds to a given geographical coordinate (LatLng).

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

From class java.lang.Object

Object	clone()
boolean	equals(Object arg0)
void	finalize()
final Class<?>	getClass()
int	hashCode()
final void	notify()
final void	notifyAll()
String	toString()
final void	wait(long arg0, int arg1)
final void	wait(long arg0)
final void	wait()

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.