/*
* Copyright (c) 2009-2012 jMonkeyEngine
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of 'jMonkeyEngine' nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.jme3.system.lwjgl;
import com.jme3.math.FastMath;
import com.jme3.system.Timer;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.lwjgl.Sys;
/**
* <code>Timer</code> handles the system's time related functionality. This
* allows the calculation of the framerate. To keep the framerate calculation
* accurate, a call to update each frame is required. <code>Timer</code> is a
* singleton object and must be created via the <code>getTimer</code> method.
*
* @author Mark Powell
* @version $Id: LWJGLTimer.java,v 1.21 2007/09/22 16:46:35 irrisor Exp $
*/
public class LwjglSmoothingTimer extends Timer {
private static final Logger logger = Logger.getLogger(LwjglSmoothingTimer.class
.getName());
private long lastFrameDiff;
//frame rate parameters.
private long oldTime;
private float lastTPF, lastFPS;
public static int TIMER_SMOOTHNESS = 32;
private long[] tpf;
private int smoothIndex;
private final static long LWJGL_TIMER_RES = Sys.getTimerResolution();
private final static float INV_LWJGL_TIMER_RES = ( 1f / LWJGL_TIMER_RES );
private static float invTimerRezSmooth;
public final static long LWJGL_TIME_TO_NANOS = (1000000000 / LWJGL_TIMER_RES);
private long startTime;
private boolean allSmooth = false;
/**
* Constructor builds a <code>Timer</code> object. All values will be
* initialized to it's default values.
*/
public LwjglSmoothingTimer() {
reset();
//print timer resolution info
logger.log(Level.FINE, "Timer resolution: {0} ticks per second", LWJGL_TIMER_RES);
}
public void reset() {
lastFrameDiff = 0;
lastFPS = 0;
lastTPF = 0;
// init to -1 to indicate this is a new timer.
oldTime = -1;
//reset time
startTime = Sys.getTime();
tpf = new long[TIMER_SMOOTHNESS];
smoothIndex = TIMER_SMOOTHNESS - 1;
invTimerRezSmooth = ( 1f / (LWJGL_TIMER_RES * TIMER_SMOOTHNESS));
// set tpf... -1 values will not be used for calculating the average in update()
for ( int i = tpf.length; --i >= 0; ) {
tpf[i] = -1;
}
}
/**
* @see Timer#getTime()
*/
public long getTime() {
return Sys.getTime() - startTime;
}
/**
* @see Timer#getResolution()
*/
public long getResolution() {
return LWJGL_TIMER_RES;
}
/**
* <code>getFrameRate</code> returns the current frame rate since the last
* call to <code>update</code>.
*
* @return the current frame rate.
*/
public float getFrameRate() {
return lastFPS;
}
public float getTimePerFrame() {
return lastTPF;
}
/**
* <code>update</code> recalulates the frame rate based on the previous
* call to update. It is assumed that update is called each frame.
*/
public void update() {
long newTime = Sys.getTime();
long oldTime = this.oldTime;
this.oldTime = newTime;
if ( oldTime == -1 ) {
// For the first frame use 60 fps. This value will not be counted in further averages.
// This is done so initialization code between creating the timer and the first
// frame is not counted as a single frame on it's own.
lastTPF = 1 / 60f;
lastFPS = 1f / lastTPF;
return;
}
long frameDiff = newTime - oldTime;
long lastFrameDiff = this.lastFrameDiff;
if ( lastFrameDiff > 0 && frameDiff > lastFrameDiff *100 ) {
frameDiff = lastFrameDiff *100;
}
this.lastFrameDiff = frameDiff;
tpf[smoothIndex] = frameDiff;
smoothIndex--;
if ( smoothIndex < 0 ) {
smoothIndex = tpf.length - 1;
}
lastTPF = 0.0f;
if (!allSmooth) {
int smoothCount = 0;
for ( int i = tpf.length; --i >= 0; ) {
if ( tpf[i] != -1 ) {
lastTPF += tpf[i];
smoothCount++;
}
}
if (smoothCount == tpf.length)
allSmooth = true;
lastTPF *= ( INV_LWJGL_TIMER_RES / smoothCount );
} else {
for ( int i = tpf.length; --i >= 0; ) {
if ( tpf[i] != -1 ) {
lastTPF += tpf[i];
}
}
lastTPF *= invTimerRezSmooth;
}
if ( lastTPF < FastMath.FLT_EPSILON ) {
lastTPF = FastMath.FLT_EPSILON;
}
lastFPS = 1f / lastTPF;
}
/**
* <code>toString</code> returns the string representation of this timer
* in the format: <br>
* <br>
* jme.utility.Timer@1db699b <br>
* Time: {LONG} <br>
* FPS: {LONG} <br>
*
* @return the string representation of this object.
*/
@Override
public String toString() {
String string = super.toString();
string += "\nTime: " + oldTime;
string += "\nFPS: " + getFrameRate();
return string;
}
}