com.jogamp.newt.event
Class PinchToZoomGesture

java.lang.Object
  com.jogamp.newt.event.PinchToZoomGesture

All Implemented Interfaces:

GestureHandler

public class PinchToZoomGesture
extends Object
implements GestureHandler

2 pointer zoom, a.k.a. pinch to zoom, gesture handler processing MouseEvents while producing PinchToZoomGesture.ZoomEvents if gesture is completed.

Zoom value lies within [0..2], with 1 as 1:1.

   - choosing the smallest surface edge (width/height -> x/y)
   - tolerating other fingers to be pressed and hence user to add functionality (scale, ..)
 

Nested Class Summary

static class

PinchToZoomGesture.ZoomEvent A GestureHandler.GestureEvent denominating zoom.

Nested classes/interfaces inherited from interface com.jogamp.newt.event.GestureHandler

GestureHandler.GestureEvent, GestureHandler.GestureListener

Field Summary

static boolean

DEBUG

Constructor Summary

PinchToZoomGesture(NativeSurface surface, boolean allowMorePointer)

Method Summary

void	clear(boolean clearStarted) Clears state of handler, i.e.
InputEvent	getGestureEvent() Returns the corresponding InputEvent for the gesture as detected by a previous GestureHandler.process(InputEvent), which has not been cleared.
float	getZoom() Zoom value lies within [0..2], with 1 as 1:1.
boolean	hasGesture() Returns true if a previous GestureHandler.process(InputEvent) command produced a gesture, which has not been cleared.
boolean	isWithinGesture() Returns true if within a gesture as detected by a previous GestureHandler.process(InputEvent) command, which has not been cleared.
boolean	process(InputEvent in) Process the given InputEvent and returns true if it produced the gesture.
void	setZoom(float zoom) Set zoom value within [0..2], with 1 as 1:1.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

DEBUG

public static final boolean DEBUG

Constructor Detail

PinchToZoomGesture

public PinchToZoomGesture(NativeSurface surface,
                          boolean allowMorePointer)

Parameters:

surface - the NativeSurface, which size is used to compute the relative zoom factor

allowMorePointer - if false, allow only 2 pressed pointers (safe and recommended), otherwise accept other pointer to be pressed.

Method Detail

toString

public String toString()

Overrides:

toString in class Object

clear

public void clear(boolean clearStarted)

Description copied from interface: GestureHandler

Clears state of handler, i.e. resets all states incl. previous detected gesture.

Specified by:

clear in interface GestureHandler

Parameters:

clearStarted - if true, also clears started state, otherwise stay within gesture - if appropriate. Staying within a gesture allows fluent continuous gesture sequence, e.g. for scrolling.

isWithinGesture

public boolean isWithinGesture()

Description copied from interface: GestureHandler

Returns true if within a gesture as detected by a previous GestureHandler.process(InputEvent) command, which has not been cleared. Otherwise returns false.

Specified by:

isWithinGesture in interface GestureHandler

hasGesture

public boolean hasGesture()

Description copied from interface: GestureHandler

Returns true if a previous GestureHandler.process(InputEvent) command produced a gesture, which has not been cleared. Otherwise returns false.

Specified by:

hasGesture in interface GestureHandler

getGestureEvent

public InputEvent getGestureEvent()

Description copied from interface: GestureHandler

Returns the corresponding InputEvent for the gesture as detected by a previous GestureHandler.process(InputEvent), which has not been cleared. Otherwise returns null.

Only implemented for gestures mapping to InputEvents.

Specified by:

getGestureEvent in interface GestureHandler

getZoom

public final float getZoom()

Zoom value lies within [0..2], with 1 as 1:1.

setZoom

public final void setZoom(float zoom)

Set zoom value within [0..2], with 1 as 1:1.

process

public boolean process(InputEvent in)

Description copied from interface: GestureHandler

Process the given InputEvent and returns true if it produced the gesture. Otherwise returns false.

If a gesture was already detected previously and has not been cleared, method does not process the event and returns true.

Besides validation of the event's details, the handler may also validate the InputEvent.InputClass and/or InputEvent.InputType.

Specified by:

process in interface GestureHandler