Files
opsu-dance/src/itdelatrisu/opsu/ui/animations/AnimatedValue.java
Jeffrey Han cd3d53336d A couple of API improvements.
Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>
2015-09-03 22:16:52 -05:00

135 lines
3.3 KiB
Java

/*
* opsu! - an open-source osu! client
* Copyright (C) 2014, 2015 Jeffrey Han
*
* opsu! is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* opsu! 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with opsu!. If not, see <http://www.gnu.org/licenses/>.
*/
package itdelatrisu.opsu.ui.animations;
import itdelatrisu.opsu.Utils;
/**
* Utility class for updating a value using an animation equation.
*/
public class AnimatedValue {
/** The animation duration, in milliseconds. */
private int duration;
/** The current time, in milliseconds. */
private int time;
/** The base value. */
private float base;
/** The maximum difference from the base value. */
private float diff;
/** The current value. */
private float value;
/** The animation equation to use. */
private AnimationEquation eqn;
/**
* Constructor.
* @param duration the total animation duration, in milliseconds
* @param min the minimum value
* @param max the maximum value
* @param eqn the animation equation to use
*/
public AnimatedValue(int duration, float min, float max, AnimationEquation eqn) {
this.time = 0;
this.duration = duration;
this.value = min;
this.base = min;
this.diff = max - min;
this.eqn = eqn;
}
/**
* Returns the current value.
*/
public float getValue() { return value; }
/**
* Returns the current animation time, in milliseconds.
*/
public int getTime() { return time; }
/**
* Sets the animation time manually.
* @param time the new time, in milliseconds
*/
public void setTime(int time) {
this.time = Utils.clamp(time, 0, duration);
updateValue();
}
/**
* Returns the total animation duration, in milliseconds.
*/
public int getDuration() { return duration; }
/**
* Sets the animation duration.
* @param duration the new duration, in milliseconds
*/
public void setDuration(int duration) {
this.duration = duration;
int newTime = Utils.clamp(time, 0, duration);
if (time != newTime) {
this.time = newTime;
updateValue();
}
}
/**
* Returns the animation equation being used.
*/
public AnimationEquation getEquation() { return eqn; }
/**
* Sets the animation equation to use.
* @param eqn the new equation
*/
public void setEquation(AnimationEquation eqn) {
this.eqn = eqn;
updateValue();
}
/**
* Updates the animation by a delta interval.
* @param delta the delta interval since the last call.
* @return true if an update was applied, false if the animation was not updated
*/
public boolean update(int delta) {
int newTime = Utils.clamp(time + delta, 0, duration);
if (time != newTime) {
this.time = newTime;
updateValue();
return true;
}
return false;
}
/**
* Recalculates the value by applying the animation equation with the current time.
*/
private void updateValue() {
float t = eqn.calc((float) time / duration);
this.value = base + (t * diff);
}
}