com.sun.javafx.tk.quantum.ZoomGestureRecognizer Maven / Gradle / Ivy
The newest version!
/*
* Copyright (c) 2014, 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.javafx.tk.quantum;
import com.sun.glass.events.KeyEvent;
import com.sun.glass.events.TouchEvent;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.HashMap;
import java.util.Map;
import javafx.util.Duration;
import javafx.scene.input.ZoomEvent;
import javafx.animation.Interpolator;
import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
class ZoomGestureRecognizer implements GestureRecognizer {
// gesture will be activated if |zoomFactor - 1| > ZOOM_FACTOR_THRESHOLD
private static double ZOOM_FACTOR_THRESHOLD = 0.1;
private static boolean ZOOM_INERTIA_ENABLED = true;
private static double MAX_ZOOMIN_VELOCITY = 3.0;
private static double MAX_ZOOMOUT_VELOCITY = 0.3333;
private static double ZOOM_INERTIA_MILLIS = 500;
private static double MAX_ZOOM_IN_FACTOR = 10;
private static double MAX_ZOOM_OUT_FACTOR = 0.1;
static {
@SuppressWarnings("removal")
var dummy = AccessController.doPrivileged((PrivilegedAction) () -> {
String s = System.getProperty("com.sun.javafx.gestures.zoom.threshold");
if (s != null) {
ZOOM_FACTOR_THRESHOLD = Double.valueOf(s);
}
s = System.getProperty("com.sun.javafx.gestures.zoom.inertia");
if (s != null) {
ZOOM_INERTIA_ENABLED = Boolean.valueOf(s);
}
return null;
});
}
private ViewScene scene;
private Timeline inertiaTimeline = new Timeline();
private DoubleProperty inertiaZoomVelocity = new SimpleDoubleProperty();
private double initialInertiaZoomVelocity = 0;
private double zoomStartTime = 0;
private double lastTouchEventTime = 0;
private ZoomRecognitionState state = ZoomRecognitionState.IDLE;
private Map trackers = new HashMap<>();
private int modifiers;
private boolean direct;
private int currentTouchCount = 0;
private boolean touchPointsSetChanged;
private boolean touchPointsPressed;
private double centerX, centerY;
private double centerAbsX, centerAbsY;
private double currentDistance;
private double distanceReference;
private double zoomFactor = 1.0;
private double totalZoomFactor = 1.0;
double inertiaLastTime = 0;
ZoomGestureRecognizer(final ViewScene scene) {
this.scene = scene;
inertiaZoomVelocity.addListener(valueModel -> {
double currentTime = inertiaTimeline.getCurrentTime().toSeconds();
double timePassed = currentTime - inertiaLastTime;
inertiaLastTime = currentTime;
double prevTotalZoomFactor = totalZoomFactor;
totalZoomFactor += timePassed * inertiaZoomVelocity.get(); // zoom += dz/dt * time
zoomFactor = totalZoomFactor / prevTotalZoomFactor;
//send inertia zoom event
sendZoomEvent(true);
});
}
@Override
public void notifyBeginTouchEvent(long time, int modifiers, boolean isDirect,
int touchEventCount) {
params(modifiers, isDirect);
touchPointsSetChanged = false;
touchPointsPressed = false;
}
@Override
public void notifyNextTouchEvent(long time, int type, long touchId,
int x, int y, int xAbs, int yAbs) {
switch(type) {
case TouchEvent.TOUCH_PRESSED:
touchPointsSetChanged = true;
touchPointsPressed = true;
touchPressed(touchId, time, x, y, xAbs, yAbs);
break;
case TouchEvent.TOUCH_STILL:
break;
case TouchEvent.TOUCH_MOVED:
touchMoved(touchId, time, x, y, xAbs, yAbs);
break;
case TouchEvent.TOUCH_RELEASED:
touchPointsSetChanged = true;
touchReleased(touchId, time, x, y, xAbs, yAbs);
break;
default:
throw new RuntimeException("Error in Zoom gesture recognition: "
+ "unknown touch state: " + state);
}
}
private void calculateCenter() {
if (currentTouchCount <= 0) {
throw new RuntimeException("Error in Zoom gesture recognition: "
+ "touch count is zero!");
}
double totalX = 0.0;
double totalY = 0.0;
double totalAbsX = 0.0;
double totalAbsY = 0.0;
for (TouchPointTracker tracker : trackers.values()) {
totalX += tracker.getX();
totalY += tracker.getY();
totalAbsX += tracker.getAbsX();
totalAbsY += tracker.getAbsY();
}
centerX = totalX / currentTouchCount;
centerY = totalY / currentTouchCount;
centerAbsX = totalAbsX / currentTouchCount;
centerAbsY = totalAbsY / currentTouchCount;
}
private double calculateMaxDistance() {
//calculate max square distance from a touch point to the center
double maxSquareDist = 0.0;
for (TouchPointTracker tracker : trackers.values()) {
double deltaX = tracker.getAbsX() - centerAbsX;
double deltaY = tracker.getAbsY() - centerAbsY;
double squareDist = deltaX * deltaX + deltaY * deltaY;
if (squareDist > maxSquareDist) {
maxSquareDist = squareDist;
}
}
return Math.sqrt(maxSquareDist);
}
@Override
public void notifyEndTouchEvent(long time) {
lastTouchEventTime = time;
if (currentTouchCount != trackers.size()) {
throw new RuntimeException("Error in Zoom gesture recognition: "
+ "touch count is wrong: " + currentTouchCount);
}
if (currentTouchCount == 0) {
if (state == ZoomRecognitionState.ACTIVE) {
sendZoomFinishedEvent();
}
if (ZOOM_INERTIA_ENABLED && (state == ZoomRecognitionState.PRE_INERTIA || state == ZoomRecognitionState.ACTIVE)) {
double timeFromLastZoom = ((double)time - zoomStartTime) / 1000000;
if (initialInertiaZoomVelocity != 0 && timeFromLastZoom < 200) {
state = ZoomRecognitionState.INERTIA;
// activate inertia
inertiaLastTime = 0;
double duration = ZOOM_INERTIA_MILLIS / 1000;
double newZoom = totalZoomFactor + initialInertiaZoomVelocity * duration;
if (initialInertiaZoomVelocity > 0) {
//zoom in
if (newZoom / totalZoomFactor > MAX_ZOOM_IN_FACTOR) {
newZoom = totalZoomFactor * MAX_ZOOM_IN_FACTOR;
duration = (newZoom - totalZoomFactor) / initialInertiaZoomVelocity;
}
} else {
//zoom out
if (newZoom / totalZoomFactor < MAX_ZOOM_OUT_FACTOR) {
newZoom = totalZoomFactor * MAX_ZOOM_OUT_FACTOR;
duration = (newZoom - totalZoomFactor) / initialInertiaZoomVelocity;
}
}
inertiaTimeline.getKeyFrames().setAll(
new KeyFrame(
Duration.millis(0),
new KeyValue(inertiaZoomVelocity, initialInertiaZoomVelocity, Interpolator.LINEAR)),
new KeyFrame(
//Duration.millis(ZOOM_INERTIA_MILLIS * Math.abs(initialInertiaZoomVelocity - 1) / (MAX_ZOOMIN_VELOCITY - 1)),
Duration.seconds(duration),
event -> {
//stop inertia
reset();
},
new KeyValue(inertiaZoomVelocity, 0, Interpolator.LINEAR))
);
inertiaTimeline.playFromStart();
} else {
reset();
}
} else {
reset();
}
} else {
// currentTouchCount >= 1
if (touchPointsPressed && state == ZoomRecognitionState.INERTIA) {
//Stop inertia
inertiaTimeline.stop();
reset();
}
if (currentTouchCount == 1) {
if (state == ZoomRecognitionState.ACTIVE) {
sendZoomFinishedEvent();
if (ZOOM_INERTIA_ENABLED) {
//prepare for inertia
state = ZoomRecognitionState.PRE_INERTIA;
} else {
reset();
}
}
} else {
// currentTouchCount >= 2
if (state == ZoomRecognitionState.IDLE) {
state = ZoomRecognitionState.TRACKING;
zoomStartTime = time;
}
calculateCenter();
double currentDistance = calculateMaxDistance();
if (touchPointsSetChanged) {
//No zoom event.
//Just update the distance reference. Keep the total zoomfactor
distanceReference = currentDistance;
} else {
zoomFactor = currentDistance / distanceReference;
if (state == ZoomRecognitionState.TRACKING) {
if ( Math.abs(zoomFactor - 1) > ZOOM_FACTOR_THRESHOLD) {
state = ZoomRecognitionState.ACTIVE;
sendZoomStartedEvent();
}
}
if (state == ZoomRecognitionState.ACTIVE) {
double prevTotalZoomFactor = totalZoomFactor;
totalZoomFactor *= zoomFactor;
sendZoomEvent(false);
distanceReference = currentDistance;
double timePassed = ((double)time - zoomStartTime) / 1000000000;
if (timePassed > 1e-4) {
initialInertiaZoomVelocity = (totalZoomFactor - prevTotalZoomFactor) / timePassed;
zoomStartTime = time;
} else {
initialInertiaZoomVelocity = 0;
}
}
}
}
}
}
@SuppressWarnings("removal")
private void sendZoomStartedEvent() {
AccessController.doPrivileged((PrivilegedAction) () -> {
if (scene.sceneListener != null) {
scene.sceneListener.zoomEvent(ZoomEvent.ZOOM_STARTED,
1, 1,
centerX, centerY,
centerAbsX, centerAbsY,
(modifiers & KeyEvent.MODIFIER_SHIFT) != 0,
(modifiers & KeyEvent.MODIFIER_CONTROL) != 0,
(modifiers & KeyEvent.MODIFIER_ALT) != 0,
(modifiers & KeyEvent.MODIFIER_WINDOWS) != 0,
direct,
false /*inertia*/);
}
return null;
}, scene.getAccessControlContext());
}
@SuppressWarnings("removal")
private void sendZoomEvent(boolean isInertia) {
AccessController.doPrivileged((PrivilegedAction) () -> {
if (scene.sceneListener != null) {
scene.sceneListener.zoomEvent(ZoomEvent.ZOOM,
zoomFactor, totalZoomFactor,
centerX, centerY,
centerAbsX, centerAbsY,
(modifiers & KeyEvent.MODIFIER_SHIFT) != 0,
(modifiers & KeyEvent.MODIFIER_CONTROL) != 0,
(modifiers & KeyEvent.MODIFIER_ALT) != 0,
(modifiers & KeyEvent.MODIFIER_WINDOWS) != 0,
direct, isInertia);
}
return null;
}, scene.getAccessControlContext());
}
@SuppressWarnings("removal")
private void sendZoomFinishedEvent() {
AccessController.doPrivileged((PrivilegedAction) () -> {
if (scene.sceneListener != null) {
scene.sceneListener.zoomEvent(ZoomEvent.ZOOM_FINISHED,
1, totalZoomFactor,
centerX, centerY,
centerAbsX, centerAbsY,
(modifiers & KeyEvent.MODIFIER_SHIFT) != 0,
(modifiers & KeyEvent.MODIFIER_CONTROL) != 0,
(modifiers & KeyEvent.MODIFIER_ALT) != 0,
(modifiers & KeyEvent.MODIFIER_WINDOWS) != 0,
direct,
false /*inertia*/);
}
return null;
}, scene.getAccessControlContext());
}
public void params(int modifiers, boolean direct) {
this.modifiers = modifiers;
this.direct = direct;
}
public void touchPressed(long id, long nanos, int x, int y, int xAbs, int yAbs) {
currentTouchCount++;
TouchPointTracker tracker = new TouchPointTracker();
tracker.update(nanos, x, y, xAbs, yAbs);
trackers.put(id, tracker);
}
public void touchReleased(long id, long nanos, int x, int y, int xAbs, int yAbs) {
if (state != ZoomRecognitionState.FAILURE) {
TouchPointTracker tracker = trackers.get(id);
if (tracker == null) {
// we don't know this ID, something went completely wrong
state = ZoomRecognitionState.FAILURE;
throw new RuntimeException("Error in Zoom gesture "
+ "recognition: released unknown touch point");
}
trackers.remove(id);
}
currentTouchCount--;
}
public void touchMoved(long id, long nanos, int x, int y, int xAbs, int yAbs) {
if (state == ZoomRecognitionState.FAILURE) {
return;
}
TouchPointTracker tracker = trackers.get(id);
if (tracker == null) {
// we don't know this ID, something went completely wrong
state = ZoomRecognitionState.FAILURE;
throw new RuntimeException("Error in zoom gesture "
+ "recognition: reported unknown touch point");
}
tracker.update(nanos, x, y, xAbs, yAbs);
}
void reset() {
state = ZoomRecognitionState.IDLE;
zoomFactor = 1.0;
totalZoomFactor = 1.0;
}
private static class TouchPointTracker {
double x, y;
double absX, absY;
public void update(long nanos, double x, double y, double absX, double absY) {
this.x = x;
this.y = y;
this.absX = absX;
this.absY = absY;
}
public double getX() {
return x;
}
public double getY() {
return y;
}
public double getAbsX() {
return absX;
}
public double getAbsY() {
return absY;
}
}
private enum ZoomRecognitionState {
IDLE, // <2 touch points available
TRACKING, // 2+ touch points, distance is tracked
ACTIVE, // threshold accepted, gesture is started
PRE_INERTIA, // prepare for inertia
INERTIA, // inertia is active
FAILURE
}
}