/*
* Copyright (c) 2006 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
* MICROSYSTEMS, 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 jogamp.opengl;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.List;
import com.jogamp.common.ExceptionUtils;
import com.jogamp.common.util.InterruptSource;
import com.jogamp.common.util.InterruptedRuntimeException;
import com.jogamp.opengl.GLContext;
/** Singleton thread upon which all OpenGL work is performed by
default. Unfortunately many vendors' OpenGL drivers are not really
thread-safe and stability is much improved by performing OpenGL
work on at most one thread. This is the default behavior of the
GLAutoDrawable implementations according to the {@link
com.jogamp.opengl.Threading Threading} class. The GLWorkerThread
replaces the original AWT event queue thread-based mechanism for
two reasons: first, more than one AWT event queue thread may be
spawned, for example if a dialog is being shown; second, it avoids
blocking the AWT event queue thread during OpenGL rendering. */
public class GLWorkerThread {
private static volatile boolean started;
private static volatile Thread thread;
private static Object lock;
private static volatile boolean shouldTerminate;
private static volatile Throwable exception;
// The Runnable to execute immediately on the worker thread
private static volatile Runnable work;
// Queue of Runnables to be asynchronously invoked
private static List<Runnable> queue = new ArrayList<Runnable>();
/** Should only be called by Threading class if creation of the
GLWorkerThread was requested via the opengl.1thread system
property. <br>
* Start the GLWorkerThread iff not started yet!
*/
public static void start() {
if (!started) { // volatile: ok
synchronized (GLWorkerThread.class) {
if (!started) {
lock = new Object();
final WorkerRunnable worker = new WorkerRunnable();
thread = new InterruptSource.Thread(null, worker, "JOGL-GLWorkerThread-");
thread.setDaemon(true);
started = true;
synchronized (lock) {
thread.start();
try {
while(!worker.isRunning) {
lock.wait();
}
} catch (final InterruptedException e) {
throw new InterruptedRuntimeException(e);
}
}
/*
// Note: it appears that there is a bug in NVidia's current
// drivers where if a context was ever made current on a
// given thread and that thread has exited before program
// exit, a crash occurs in the drivers. Releasing the
// context from the given thread does not work around the
// problem.
//
// For the time being, we're going to work around this
// problem by not terminating the GLWorkerThread. In theory,
// shutting down the GLWorkerThread cleanly could be a good
// general solution to the problem of needing to
// cooperatively terminate all Animators at program exit.
//
// It appears that this doesn't even work around all of the
// kinds of crashes. Causing the context to be unilaterally
// released from the GLWorkerThread after each invocation
// seems to work around all of the kinds of crashes seen.
//
// These appear to be similar to the kinds of crashes seen
// when the Java2D/OpenGL pipeline terminates, and those are
// a known issue being fixed, so presumably these will be
// fixed in NVidia's next driver set.
// Install shutdown hook to terminate daemon thread more or
// less cooperatively
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
Runtime.getRuntime().addShutdownHook(new InterruptSource.Thread() {
public void run() {
Object lockTemp = lock;
if (lockTemp == null) {
// Already terminating (?)
return;
}
synchronized (lockTemp) {
shouldTerminate = true;
lockTemp.notifyAll();
try {
lockTemp.wait(500);
} catch (InterruptedException e) {
}
}
}
});
return null;
}
});
*/
} else {
throw new RuntimeException(getThreadName()+": Should not start GLWorkerThread twice");
}
}
}
}
public static void invoke(final boolean wait, final Runnable runnable)
throws InvocationTargetException, InterruptedException {
if(wait) {
invokeAndWait(runnable);
} else {
invokeLater(runnable);
}
}
public static void invokeAndWait(final Runnable runnable)
throws InvocationTargetException, InterruptedException {
if (!started) {
throw new RuntimeException(getThreadName()+": May not invokeAndWait on worker thread without starting it first");
}
final Object lockTemp = lock;
if (lockTemp == null) {
return; // Terminating
}
synchronized (lockTemp) {
if (thread == null) {
// Terminating
return;
}
work = runnable;
lockTemp.notifyAll();
while( null != work ) {
lockTemp.wait();
}
if (exception != null) {
final Throwable localException = exception;
exception = null;
throw new InvocationTargetException(localException);
}
}
}
public static void invokeLater(final Runnable runnable) {
if (!started) {
throw new RuntimeException(getThreadName()+": May not invokeLater on worker thread without starting it first");
}
final Object lockTemp = lock;
if (lockTemp == null) {
return; // Terminating
}
synchronized (lockTemp) {
if (thread == null) {
// Terminating
return;
}
queue.add(runnable);
lockTemp.notifyAll();
}
}
/** Indicates whether the OpenGL worker thread was started, i.e.,
whether it is currently in use. */
public static boolean isStarted() {
return started;
}
/** Indicates whether the current thread is the OpenGL worker
thread. */
public static boolean isWorkerThread() {
return (Thread.currentThread() == thread);
}
protected static String getThreadName() { return Thread.currentThread().getName(); }
static class WorkerRunnable implements Runnable {
volatile boolean isRunning = false;
@Override
public void run() {
// Notify starting thread that we're ready
synchronized (lock) {
isRunning = true;
lock.notifyAll();
}
while (!shouldTerminate) {
synchronized (lock) {
while (!shouldTerminate &&
(work == null) &&
queue.isEmpty()) {
try {
// Avoid race conditions with wanting to release contexts on this thread
lock.wait(1000);
} catch (final InterruptedException e) {
throw new InterruptedRuntimeException(e);
}
if (GLContext.getCurrent() != null) {
// Test later to see whether we need to release this context
break;
}
}
if (shouldTerminate) {
lock.notifyAll();
thread = null;
lock = null;
return;
}
if (work != null) {
try {
work.run();
} catch (final Throwable t) {
exception = t;
} finally {
work = null;
lock.notifyAll();
}
}
while (!queue.isEmpty()) {
try {
final Runnable curAsync = queue.remove(0);
curAsync.run();
} catch (final Throwable t) {
ExceptionUtils.dumpThrowable("suppressed", t); // Noncancelable
}
}
// See about releasing current context
final GLContext curContext = GLContext.getCurrent();
if (curContext != null &&
(curContext instanceof GLContextImpl)) {
final GLContextImpl impl = (GLContextImpl) curContext;
if (impl.hasWaiters()) {
impl.release();
}
}
}
}
isRunning = false;
}
}
}