com.sun.glass.ui.monocle.SmallMoveTouchFilter Maven / Gradle / Ivy
/*
* Copyright (c) 2014, 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.glass.ui.monocle;
/**
* This TouchFilter stabilizes touch points, eliminating moves below a certain
* threshold.
*/
final class SmallMoveTouchFilter implements TouchFilter {
private final TouchState oldState = new TouchState();
private final int radius = TouchInput.getInstance()
.getTouchRadius();
SmallMoveTouchFilter() {
TouchInput.getInstance().getState(oldState);
}
@Override
public int getPriority() {
return PRIORITY_POST_ID;
}
@Override
public boolean filter(TouchState state) {
for (int i = 0; i < oldState.getPointCount(); i++) {
TouchState.Point oldPoint = oldState.getPoint(i);
TouchState.Point newPoint = state.getPointForID(oldPoint.id);
if (newPoint != null) {
int dx = newPoint.x - oldPoint.x;
int dy = newPoint.y - oldPoint.y;
int dist2 = dx * dx + dy * dy;
if (dist2 < radius * radius) {
// if this is a move, rewrite it as a stationary event
newPoint.x = oldPoint.x;
newPoint.y = oldPoint.y;
}
}
}
state.copyTo(oldState);
return false;
}
@Override
public boolean flush(TouchState state) {
return false;
}
@Override
public boolean equals(Object o) {
return o instanceof SmallMoveTouchFilter;
}
@Override
public int hashCode() {
return 0;
}
@Override
public String toString() {
return "SmallMove";
}
}