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authorKenneth Russel <[email protected]>2003-06-25 09:05:29 +0000
committerKenneth Russel <[email protected]>2003-06-25 09:05:29 +0000
commit2179980ed660ef66a9c064d153c5de7994d431ab (patch)
tree926fa0ccc31737ad9753a64bf0451dd818652d1b /src/demos/util/SystemTime.java
parent1a1ad3a33b2932187410bc8bb4bf44362a26c8b0 (diff)
Split up net.java.games.util; moved GLUT and BufferUtils into
net.java.games.jogl.util, and moved demo-specific utility classes into jogl-demos project under demos.util. Added nearly all JavaOne demos into jogl-demos project; rewrote where necessary to use ClassLoader.getResourceAsStream() instead of flat files, put into packages and added to Makefile. Added gleem to jogl-demos project. Added jogl.jar build rule. git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/../svn-server-sync/jogl-demos/trunk@3 3298f667-5e0e-4b4a-8ed4-a3559d26a5f4
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+/*
+ * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * - Redistribution of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistribution 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 Sun Microsystems, Inc. or the names of
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * This software is provided "AS IS," without a warranty of any kind. ALL
+ * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
+ * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
+ * MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
+ * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
+ * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
+ * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
+ * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
+ * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+ *
+ * You acknowledge that this software is not designed or intended for use
+ * in the design, construction, operation or maintenance of any nuclear
+ * facility.
+ *
+ * Sun gratefully acknowledges that this software was originally authored
+ * and developed by Kenneth Bradley Russell and Christopher John Kline.
+ */
+
+package demos.util;
+
+/** Implementation of {@link demos.util.Time} interface based
+ on {@link java.lang.System.currentTimeMillis}. Performs smoothing
+ internally to avoid effects of poor granularity of
+ currentTimeMillis on Windows platform in particular. */
+
+public class SystemTime implements Time {
+ private static final int DEFAULT_NUM_SMOOTHING_SAMPLES = 10;
+ private long[] samples = new long[DEFAULT_NUM_SMOOTHING_SAMPLES];
+ private int numSmoothingSamples;
+ private int curSmoothingSample; // Index of current sample to be replaced
+ private long baseTime = System.currentTimeMillis();
+ private boolean hasCurTime;
+ private double curTime;
+ private double deltaT;
+
+ /** Sets number of smoothing samples. Defaults to 10. Note that
+ there may be a discontinuity in the reported time after a call
+ to this method. */
+ public void setNumSmoothingSamples(int num) {
+ samples = new long[num];
+ numSmoothingSamples = 0;
+ curSmoothingSample = 0;
+ hasCurTime = false;
+ }
+
+ /** Returns number of smoothing samples; default is 10. */
+ public int getNumSmoothingSamples() {
+ return samples.length;
+ }
+
+ /** Rebases this timer. After very long periods of time the
+ resolution of this timer may decrease; the application can call
+ this to restore higher resolution. Note that there may be a
+ discontinuity in the reported time after a call to this
+ method. */
+ public void rebase() {
+ baseTime = System.currentTimeMillis();
+ setNumSmoothingSamples(samples.length);
+ }
+
+ public void update() {
+ long tmpTime = System.currentTimeMillis();
+ long diffSinceBase = tmpTime - baseTime;
+ samples[curSmoothingSample] = diffSinceBase;
+ curSmoothingSample = (curSmoothingSample + 1) % samples.length;
+ numSmoothingSamples = Math.min(1 + numSmoothingSamples, samples.length);
+ // Average of samples is current time
+ double newCurTime = 0.0;
+ for (int i = 0; i < numSmoothingSamples; i++) {
+ newCurTime += samples[i];
+ }
+ newCurTime /= (1000.0f * numSmoothingSamples);
+ double lastTime = curTime;
+ if (!hasCurTime) {
+ lastTime = newCurTime;
+ hasCurTime = true;
+ }
+ deltaT = newCurTime - lastTime;
+ curTime = newCurTime;
+ }
+
+ public double time() {
+ return curTime;
+ }
+
+ public double deltaT() {
+ return deltaT;
+ }
+}