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package javafx.scene.input;

import com.sun.javafx.scene.input.InputEventUtils;
import com.sun.javafx.scene.input.TouchPointHelper;
import java.io.IOException;
import java.io.Serializable;
import javafx.beans.NamedArg;
import javafx.event.EventTarget;
import javafx.geometry.Point3D;
import javafx.scene.Node;
import javafx.scene.Scene;

Touch point represents a single point of a multi-touch action, typically one finger touching a screen. It is contained in TouchEvent. 
 The touch point has its coordinates, state (see State) and ID. The ID is sequential number of this touch point unique in scope of a single multi-touch gesture. 
 Each touch point is by default delivered to a single node during its whole trajectory - to the node on which it was pressed. There is a grabbing API to modify this behavior. The above means that when touch point is pressed, it is automatically grabbed by the top-most node on the press coordinates. Any time during the gesture grab() and ungrab() methods can be used to alter the event delivery target. When grabbed by a different node, it will next time be targeted to it; when ungrabbed, it will be always targeted to the top-most node on the current location. 
Since:
JavaFX 2.2/**
 * Touch point represents a single point of a multi-touch action, typically
 * one finger touching a screen. It is contained in {@link TouchEvent}.
 * <p>
 * The touch point has its coordinates, state (see {@link State}) and ID. The
 * ID is sequential number of this touch point unique in scope of a single
 * multi-touch gesture.
 * <p>
 * Each touch point is by default delivered to a single node during its whole
 * trajectory - to the node on which it was pressed. There is a grabbing API
 * to modify this behavior. The above means that when touch point is pressed,
 * it is automatically grabbed by the top-most node on the press coordinates.
 * Any time during the gesture {@code grab()} and {@code ungrab()} methods
 * can be used to alter the event delivery target. When grabbed by a different
 * node, it will next time be targeted to it; when ungrabbed, it will be
 * always targeted to the top-most node on the current location.
 *
 * @since JavaFX 2.2
 */
public final class TouchPoint implements Serializable{

    static {
        // This is used by classes in different packages to get access to
        // private and package private methods.
        TouchPointHelper.setTouchPointAccessor(new TouchPointHelper.TouchPointAccessor() {

            @Override
            public void reset(TouchPoint touchPoint) {
                touchPoint.reset();
            }
        });
    }

    private transient EventTarget target;
    private transient Object source;

    
Creates new instance of TouchPoint.
Params:
id – ID of the new touch point
state – state of the new touch point
x – The x with respect to the scene.
y – The y with respect to the scene.
screenX – The x coordinate relative to screen.
screenY – The y coordinate relative to screen.
target – Node or other event target.
pickResult – pick result. Can be null, in this case a 2D pick result
                  without any further values is constructed
                  based on the scene coordinates and target
Since:
JavaFX 8.0/**
     * Creates new instance of TouchPoint.
     * @param id ID of the new touch point
     * @param state state of the new touch point
     * @param x The x with respect to the scene.
     * @param y The y with respect to the scene.
     * @param screenX The x coordinate relative to screen.
     * @param screenY The y coordinate relative to screen.
     * @param target Node or other event target.
     * @param pickResult pick result. Can be null, in this case a 2D pick result
     *                   without any further values is constructed
     *                   based on the scene coordinates and target
     * @since JavaFX 8.0
     */
    public TouchPoint(@NamedArg("id") int id, @NamedArg("state") State state, @NamedArg("x") double x, @NamedArg("y") double y, @NamedArg("screenX") double screenX,
            @NamedArg("screenY") double screenY, @NamedArg("target") EventTarget target, @NamedArg("pickResult") PickResult pickResult) {
        this.target = target;
        this.id = id;
        this.state = state;
        this.x = x;
        this.y = y;
        this.sceneX = x;
        this.sceneY = y;
        this.screenX = screenX;
        this.screenY = screenY;
        this.pickResult = pickResult != null ? pickResult : new PickResult(target, x, y);
        final Point3D p = InputEventUtils.recomputeCoordinates(this.pickResult, null);
        this.x = p.getX();
        this.y = p.getY();
        this.z = p.getZ();
    }

    
Recomputes this touch point (coordinates, relevancy) for the given event
source object.
Params:
oldSource – Source object of the current values
newSource – Source object to compute values for/**
     * Recomputes this touch point (coordinates, relevancy) for the given event
     * source object.
     * @param oldSource Source object of the current values
     * @param newSource Source object to compute values for
     */
    void recomputeToSource(Object oldSource, Object newSource) {

        final Point3D newCoordinates = InputEventUtils.recomputeCoordinates(
                pickResult, newSource);

        x = newCoordinates.getX();
        y = newCoordinates.getY();
        z = newCoordinates.getZ();

        source = newSource;
    }

    
Distinguishes between touch points targeted to the given node or some
of its children from touch points targeted somewhere else. This allows
for testing all touch points carried by one touch event on their
relevance for a given node.
Params:
target – Node or other event target to be tested
Returns:
true if this touch point is targeted to the given target or
some of its children/**
     * Distinguishes between touch points targeted to the given node or some
     * of its children from touch points targeted somewhere else. This allows
     * for testing all touch points carried by one touch event on their
     * relevance for a given node.
     * @param target Node or other event target to be tested
     * @return true if this touch point is targeted to the given target or
     * some of its children
     */
    public boolean belongsTo(EventTarget target) {

        if (this.target instanceof Node) {
            Node n = (Node) this.target;

            if (target instanceof Scene) {
                return n.getScene() == target;
            }
            while (n != null) {
                if (n == target) {
                    return true;
                }
                n = n.getParent();
            }
        }

        return target == this.target;
    }

    void reset() {
        final Point3D p = InputEventUtils.recomputeCoordinates(pickResult, null);
        x = p.getX();
        y = p.getY();
        z = p.getZ();
    }

    private EventTarget grabbed = null;

    
Gets event target which has grabbed this touch point.
Returns:
The current grabbed target, null if the touch point is ungrabbed/**
     * Gets event target which has grabbed this touch point.
     * @return The current grabbed target, null if the touch point is ungrabbed
     */
    public EventTarget getGrabbed() {
        return grabbed;
    }

    
Grabs this touch point by current event source. Next event containing
this touch point will be targeted to the same node whose event handler
called this method.
/**
     * Grabs this touch point by current event source. Next event containing
     * this touch point will be targeted to the same node whose event handler
     * called this method.
     */
    public void grab() {
        if (source instanceof EventTarget) {
            grabbed = (EventTarget) source;
        } else {
            throw new IllegalStateException("Cannot grab touch point, "
                    + "source is not an instance of EventTarget: " + source);
        }
    }

    
Grabs this touch point by the given target. Next event containing this
touch point will be targeted to it.
Params:
target – Target by which to grab the touch point/**
     * Grabs this touch point by the given target. Next event containing this
     * touch point will be targeted to it.
     * @param target Target by which to grab the touch point
     */
    public void grab(EventTarget target) {
        grabbed = target;
    }

    
Ungrabs this touch point from its target. Since the next event this
touch point will be delivered to the top-most node picked on its
respective location until it is grabbed again or released.
/**
     * Ungrabs this touch point from its target. Since the next event this
     * touch point will be delivered to the top-most node picked on its
     * respective location until it is grabbed again or released.
     */
    public void ungrab() {
        grabbed = null;
    }

    private int id;

    
Gets identifier of this touch point. The number is sequential and unique in scope of one multi touch gesture. The first pressed touch point has id 1, each subsequently pressed touch points gets the next ordinal number until all touch points are released and the counter is reset. 
Returns:
the identifier of this touch point./**
     * Gets identifier of this touch point. The number is sequential and unique
     * in scope of one multi touch gesture. The first pressed touch point has id
     * {@code 1}, each subsequently pressed touch points gets the next ordinal
     * number until all touch points are released and the counter is reset.
     *
     * @return the identifier of this touch point.
     */
    public final int getId() {
        return id;
    }

    private State state;

    
Gets state of this touch point
Returns:
state of this touch point/**
     * Gets state of this touch point
     * @return state of this touch point
     */
    public final State getState() {
        return state;
    }


    private transient double x;

    
Gets the horizontal position of the touch point relative to the
origin of the TouchEvent's source.
Returns:
the horizontal position of the touch point relative to the
origin of the TouchEvent's source./**
     * Gets the horizontal position of the touch point relative to the
     * origin of the TouchEvent's source.
     *
     * @return the horizontal position of the touch point relative to the
     * origin of the TouchEvent's source.
     */
    public final double getX() {
        return x;
    }

    private transient double y;

    
Gets the vertical position of the touch point relative to the
origin of the TouchEvent's source.
Returns:
the vertical position of the touch point relative to the
origin of the TouchEvent's source./**
     * Gets the vertical position of the touch point relative to the
     * origin of the TouchEvent's source.
     *
     * @return the vertical position of the touch point relative to the
     * origin of the TouchEvent's source.
     */
    public final double getY() {
        return y;
    }

    
Depth z position of the event relative to the
origin of the MouseEvent's node.
/**
     * Depth z position of the event relative to the
     * origin of the MouseEvent's node.
     */
    private transient double z;

    
Depth position of the event relative to the
origin of the MouseEvent's source.
Returns:
depth position of the event relative to the
origin of the MouseEvent's source.
Since:
JavaFX 8.0/**
     * Depth position of the event relative to the
     * origin of the MouseEvent's source.
     *
     * @return depth position of the event relative to the
     * origin of the MouseEvent's source.
     * @since JavaFX 8.0
     */
    public final double getZ() {
        return z;
    }

    private double screenX;

    
Gets the absolute horizontal position of the touch point.
Returns:
the absolute horizontal position of the touch point/**
     * Gets the absolute horizontal position of the touch point.
     * @return the absolute horizontal position of the touch point
     */
    public final double getScreenX() {
        return screenX;
    }

    private double screenY;

    
Gets the absolute vertical position of the touch point.
Returns:
the absolute vertical position of the touch point/**
     * Gets the absolute vertical position of the touch point.
     * @return the absolute vertical position of the touch point
     */
    public final double getScreenY() {
        return screenY;
    }

    private double sceneX;

    
Gets the horizontal position of the touch point relative to the origin of the Scene that contains the TouchEvent's source. If the node is not in a Scene, then the value is relative to the boundsInParent of the root-most parent of the TouchEvent's node. Note that in 3D scene, this represents the flat coordinates after applying the projection transformations. 
Returns:
the horizontal position of the touch point relative to the origin of the Scene that contains the TouchEvent's source/**
     * Gets the horizontal position of the touch point relative to the
     * origin of the {@code Scene} that contains the TouchEvent's source.
     * If the node is not in a {@code Scene}, then the value is relative to
     * the boundsInParent of the root-most parent of the TouchEvent's node.
     * Note that in 3D scene, this represents the flat coordinates after
     * applying the projection transformations.
     *
     * @return the horizontal position of the touch point relative to the
     * origin of the {@code Scene} that contains the TouchEvent's source
     */
    public final double getSceneX() {
        return sceneX;
    }

    private double sceneY;

    
Gets the vertical position of the touch point relative to the origin of the Scene that contains the TouchEvent's source. If the node is not in a Scene, then the value is relative to the boundsInParent of the root-most parent of the TouchEvent's node. Note that in 3D scene, this represents the flat coordinates after applying the projection transformations. 
Returns:
the vertical position of the touch point relative to the origin of the Scene that contains the TouchEvent's source/**
     * Gets the vertical position of the touch point relative to the
     * origin of the {@code Scene} that contains the TouchEvent's source.
     * If the node is not in a {@code Scene}, then the value is relative to
     * the boundsInParent of the root-most parent of the TouchEvent's node.
     * Note that in 3D scene, this represents the flat coordinates after
     * applying the projection transformations.
     *
     * @return the vertical position of the touch point relative to the
     * origin of the {@code Scene} that contains the TouchEvent's source
     */
    public final double getSceneY() {
        return sceneY;
    }

    
Information about the pick if the picked Node is a Shape3D node and its pickOnBounds is false. /**
     * Information about the pick if the picked {@code Node} is a
     * {@code Shape3D} node and its pickOnBounds is false.
     */
    private PickResult pickResult;

    
Returns information about the pick.
Returns:
new PickResult object that contains information about the pick
Since:
JavaFX 8.0/**
     * Returns information about the pick.
     *
     * @return new PickResult object that contains information about the pick
     * @since JavaFX 8.0
     */
    public final PickResult getPickResult() {
        return pickResult;
    }

    
Gets event target on which the touch event carrying this touch point
is fired.
Returns:
Event target for this touch point/**
     * Gets event target on which the touch event carrying this touch point
     * is fired.
     * @return Event target for this touch point
     */
    public EventTarget getTarget() {
        return target;
    }

    
Returns a string representation of this TouchPoint object. 
Returns:
a string representation of this TouchPoint object./**
     * Returns a string representation of this {@code TouchPoint} object.
     * @return a string representation of this {@code TouchPoint} object.
     */
    @Override public String toString() {
        final StringBuilder sb = new StringBuilder("TouchPoint [");

        sb.append("state = ").append(getState());
        sb.append(", id = ").append(getId());
        sb.append(", target = ").append(getTarget());
        sb.append(", x = ").append(getX()).append(", y = ").append(getY())
                .append(", z = ").append(getZ());
        sb.append(", pickResult = ").append(getPickResult());

        return sb.append("]").toString();
    }

    private void readObject(java.io.ObjectInputStream in)
            throws IOException, ClassNotFoundException {
        in.defaultReadObject();
        x = sceneX;
        y = sceneY;
    }

    
Represents current state of the touch point
Since:
JavaFX 2.2/**
     * Represents current state of the touch point
     *
     * @since JavaFX 2.2
     */
    public enum State {
        
The touch point has just been pressed (touched for the first time)
/**
         * The touch point has just been pressed (touched for the first time)
         */
        PRESSED,
        
The touch point has been moved
/**
         * The touch point has been moved
         */
        MOVED,
        
The touch point remains pressed and still (without moving)
/**
         * The touch point remains pressed and still (without moving)
         */
        STATIONARY,
        
The touch point has been released
/**
         * The touch point has been released
         */
        RELEASED
    }
}