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Fix the new accurate Display.sync() method to use less CPU on Mac.

This commit is contained in:
kappa1 2012-03-18 16:25:23 +00:00
parent 093bfe9698
commit e0c6b24536
1 changed files with 38 additions and 24 deletions
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62
src/java/org/lwjgl/opengl/Display.java
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@ -85,6 +85,9 @@ public final class Display {
/** Whether the sync() method has been initiated */
private static boolean syncInitiated;
/** whether to disable adaptive yield time in sync() method */
private static boolean adaptiveTimeDisabled;
/** adaptive time to yield instead of sleeping in sync()*/
private static long adaptiveYieldTime;
@ -419,7 +422,7 @@ public final class Display {
long sleepTime = 1000000000 / fps; // nanoseconds to sleep this frame
// adaptiveYieldTime + remainder micro & nano seconds if smaller than sleepTime
long yieldTime = Math.min(sleepTime, adaptiveYieldTime + sleepTime % (1000*1000));
long yieldTime = adaptiveTimeDisabled ? 0 : Math.min(sleepTime, adaptiveYieldTime + sleepTime % (1000*1000));
long overSleep = 0; // time the sync goes over by
try {
@ -442,14 +445,16 @@ public final class Display {
lastTime = getTime() - Math.min(overSleep, sleepTime);
// auto tune the amount of time to yield
if (overSleep > adaptiveYieldTime) {
// increase by 200 microseconds (1/5 a ms)
adaptiveYieldTime = Math.min(adaptiveYieldTime + 200*1000, sleepTime);
}
else if (overSleep < adaptiveYieldTime - 200*1000) {
// decrease by 5 microseconds
adaptiveYieldTime = Math.max(adaptiveYieldTime - 2*1000, 0);
if (!adaptiveTimeDisabled) {
// auto tune the amount of time to yield
if (overSleep > adaptiveYieldTime) {
// increase by 200 microseconds (1/5 a ms)
adaptiveYieldTime = Math.min(adaptiveYieldTime + 200*1000, sleepTime);
}
else if (overSleep < adaptiveYieldTime - 200*1000) {
// decrease by 5 microseconds
adaptiveYieldTime = Math.max(adaptiveYieldTime - 2*1000, 0);
}
}
}
@ -462,28 +467,37 @@ public final class Display {
}
/**
* On windows the sleep functions can be highly inaccurate by
* over 10ms making in unusable. However it can be forced to
* be a bit more accurate by running a separate sleeping daemon
* thread.
* Initialise the sync(fps) method.
*/
private static void initiateSyncTimer() {
syncInitiated = true;
lastTime = getTime();
if (!System.getProperty("os.name").startsWith("Win")) {
String osName = System.getProperty("os.name");
if (osName.startsWith("Mac") || osName.startsWith("Darwin")) {
// disabled on mac as it uses too much cpu, besides
// Thread.sleep is pretty accurate on mac by default
adaptiveTimeDisabled = true;
return;
}
Thread timerAccuracyThread = new Thread(new Runnable() {
public void run() {
try {
Thread.sleep(Long.MAX_VALUE);
} catch (Exception e) {}
}
});
timerAccuracyThread.setDaemon(true);
timerAccuracyThread.start();
if (osName.startsWith("Win")) {
// On windows the sleep functions can be highly inaccurate by
// over 10ms making in unusable. However it can be forced to
// be a bit more accurate by running a separate sleeping daemon
// thread.
Thread timerAccuracyThread = new Thread(new Runnable() {
public void run() {
try {
Thread.sleep(Long.MAX_VALUE);
} catch (Exception e) {}
}
});
timerAccuracyThread.setDaemon(true);
timerAccuracyThread.start();
}
}
/** @return the title of the window */