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package sun.java2d.opengl;

import sun.awt.util.ThreadGroupUtils;
import sun.java2d.pipe.RenderBuffer;
import sun.java2d.pipe.RenderQueue;

import static sun.java2d.pipe.BufferedOpCodes.*;
import java.security.AccessController;
import java.security.PrivilegedAction;

OGL-specific implementation of RenderQueue. This class provides a single (daemon) thread that is responsible for periodically flushing the queue, thus ensuring that only one thread communicates with the native OpenGL libraries for the entire process.
/** * OGL-specific implementation of RenderQueue. This class provides a * single (daemon) thread that is responsible for periodically flushing * the queue, thus ensuring that only one thread communicates with the native * OpenGL libraries for the entire process. */
public class OGLRenderQueue extends RenderQueue { private static OGLRenderQueue theInstance; private final QueueFlusher flusher; private OGLRenderQueue() { /* * The thread must be a member of a thread group * which will not get GCed before VM exit. */ flusher = AccessController.doPrivileged((PrivilegedAction<QueueFlusher>) QueueFlusher::new); }
Returns the single OGLRenderQueue instance. If it has not yet been initialized, this method will first construct the single instance before returning it.
/** * Returns the single OGLRenderQueue instance. If it has not yet been * initialized, this method will first construct the single instance * before returning it. */
public static synchronized OGLRenderQueue getInstance() { if (theInstance == null) { theInstance = new OGLRenderQueue(); } return theInstance; }
Flushes the single OGLRenderQueue instance synchronously. If an OGLRenderQueue has not yet been instantiated, this method is a no-op. This method is useful in the case of Toolkit.sync(), in which we want to flush the OGL pipeline, but only if the OGL pipeline is currently enabled. Since this class has few external dependencies, callers need not be concerned that calling this method will trigger initialization of the OGL pipeline and related classes.
/** * Flushes the single OGLRenderQueue instance synchronously. If an * OGLRenderQueue has not yet been instantiated, this method is a no-op. * This method is useful in the case of Toolkit.sync(), in which we want * to flush the OGL pipeline, but only if the OGL pipeline is currently * enabled. Since this class has few external dependencies, callers need * not be concerned that calling this method will trigger initialization * of the OGL pipeline and related classes. */
public static void sync() { if (theInstance != null) { theInstance.lock(); try { theInstance.ensureCapacity(4); theInstance.getBuffer().putInt(SYNC); theInstance.flushNow(); } finally { theInstance.unlock(); } } }
Disposes the native memory associated with the given native graphics config info pointer on the single queue flushing thread.
/** * Disposes the native memory associated with the given native * graphics config info pointer on the single queue flushing thread. */
public static void disposeGraphicsConfig(long pConfigInfo) { OGLRenderQueue rq = getInstance(); rq.lock(); try { // make sure we make the context associated with the given // GraphicsConfig current before disposing the native resources OGLContext.setScratchSurface(pConfigInfo); RenderBuffer buf = rq.getBuffer(); rq.ensureCapacityAndAlignment(12, 4); buf.putInt(DISPOSE_CONFIG); buf.putLong(pConfigInfo); // this call is expected to complete synchronously, so flush now rq.flushNow(); } finally { rq.unlock(); } }
Returns true if the current thread is the OGL QueueFlusher thread.
/** * Returns true if the current thread is the OGL QueueFlusher thread. */
public static boolean isQueueFlusherThread() { return (Thread.currentThread() == getInstance().flusher.thread); } public void flushNow() { // assert lock.isHeldByCurrentThread(); try { flusher.flushNow(); } catch (Exception e) { System.err.println("exception in flushNow:"); e.printStackTrace(); } } public void flushAndInvokeNow(Runnable r) { // assert lock.isHeldByCurrentThread(); try { flusher.flushAndInvokeNow(r); } catch (Exception e) { System.err.println("exception in flushAndInvokeNow:"); e.printStackTrace(); } } private native void flushBuffer(long buf, int limit); private void flushBuffer() { // assert lock.isHeldByCurrentThread(); int limit = buf.position(); if (limit > 0) { // process the queue flushBuffer(buf.getAddress(), limit); } // reset the buffer position buf.clear(); // clear the set of references, since we no longer need them refSet.clear(); } private class QueueFlusher implements Runnable { private boolean needsFlush; private Runnable task; private Error error; private final Thread thread; public QueueFlusher() { String name = "Java2D Queue Flusher"; thread = new Thread(ThreadGroupUtils.getRootThreadGroup(), this, name, 0, false); thread.setDaemon(true); thread.setPriority(Thread.MAX_PRIORITY); thread.start(); } public synchronized void flushNow() { // wake up the flusher needsFlush = true; notify(); // wait for flush to complete while (needsFlush) { try { wait(); } catch (InterruptedException e) { } } // re-throw any error that may have occurred during the flush if (error != null) { throw error; } } public synchronized void flushAndInvokeNow(Runnable task) { this.task = task; flushNow(); } public synchronized void run() { boolean timedOut = false; while (true) { while (!needsFlush) { try { timedOut = false; /* * Wait until we're woken up with a flushNow() call, * or the timeout period elapses (so that we can * flush the queue periodically). */ wait(100); /* * We will automatically flush the queue if the * following conditions apply: * - the wait() timed out * - we can lock the queue (without blocking) * - there is something in the queue to flush * Otherwise, just continue (we'll flush eventually). */ if (!needsFlush && (timedOut = tryLock())) { if (buf.position() > 0) { needsFlush = true; } else { unlock(); } } } catch (InterruptedException e) { } } try { // reset the throwable state error = null; // flush the buffer now flushBuffer(); // if there's a task, invoke that now as well if (task != null) { task.run(); } } catch (Error e) { error = e; } catch (Exception x) { System.err.println("exception in QueueFlusher:"); x.printStackTrace(); } finally { if (timedOut) { unlock(); } task = null; // allow the waiting thread to continue needsFlush = false; notify(); } } } } }