The frame manager goes through a simple two part procedure every frame: * *
The ticking and rendering takes place on the AWT thread so as to avoid the need for * complicated coordination between AWT event handler code and frame code. However, this means that * all AWT (and Swing) event handlers must not perform any complicated processing. After * each frame, control of the AWT thread is given back to the AWT which processes all pending AWT * events before giving the frame manager an opportunity to process the next frame. Thus the * convenience of everything running on the AWT thread comes with the price of requiring that AWT * event handlers not block or perform any intensive processing. In general, this is a sensible * structure for an application anyhow, so this organization tends to be preferable to an * organization where the AWT and frame threads are separate and must tread lightly so as not to * collide. * *
Note: the way that JScrollPane goes about improving performance when scrolling
* complicated contents cannot work with active rendering. If you use a JScrollPane in
* an application that uses the frame manager, you should either use the provided {@link
* SafeScrollPane} or set your scroll panes' viewports to SIMPLE_SCROLL_MODE.
*/
public abstract class FrameManager
{
/**
* Normally, the frame manager will repaint any component in a {@link JLayeredPane} layer
* (popups, overlays, etc.) that overlaps a frame participant on every tick because the frame
* participant could have changed underneath the overlay which would require that the
* overlay be repainted. If the application knows that the frame participant beneath the
* overlay will never change, it can have its overlay implement this interface and avoid the
* expense of forcibly fully repainting the overlay on every frame.
*/
public static interface SafeLayerComponent
{
}
/**
* Provides a bridge between either {@link ManagedJFrame} or {@link ManagedJApplet} and the
* frame manager.
*/
public static interface ManagedRoot
{
/** Configures the root with a reference to its frame manager. */
public void init (FrameManager fmgr);
/** Returns the window at the root of the UI hierarchy. */
public Window getWindow ();
/** Returns the top-level Swing pane. */
public JRootPane getRootPane();
}
/**
* Creates a frame manager that will use a {@link SystemMediaTimer} to obtain timing
* information, which is available on every platform, but returns inaccurate time stamps on
* many platforms.
*
* @see #newInstance(ManagedRoot, MediaTimer)
*/
public static FrameManager newInstance (ManagedRoot root)
{
// first try creating a PerfTimer which is the best if we're using JDK1.4.2
MediaTimer timer = null;
try {
timer = (MediaTimer)Class.forName(PERF_TIMER).newInstance();
} catch (Throwable t) {
Log.info("Can't use PerfTimer (" + t + ") reverting to " +
"System.currentTimeMillis() based timer.");
timer = new SystemMediaTimer();
}
return newInstance(root, timer);
}
/**
* Constructs a frame manager that will do its rendering to the supplied root.
*/
public static FrameManager newInstance (ManagedRoot root, MediaTimer timer)
{
FrameManager fmgr = _useFlip.getValue() ? new FlipFrameManager() : new BackFrameManager();
fmgr.init(root, timer);
return fmgr;
}
/**
* Instructs the frame manager to target the specified number of frames per second. If the
* computation and rendering for a frame are completed with time to spare, the frame manager
* will wait until the proper time to begin processing for the next frame. If a frame takes
* longer than its alotted time, the frame manager will immediately begin processing on the
* next frame.
*/
public void setTargetFrameRate (int fps)
{
// compute the number of milliseconds per frame
_millisPerFrame = 1000/fps;
}
/**
* Registers a frame participant. The participant will be given the opportunity to do
* processing and rendering on each frame.
*/
public void registerFrameParticipant (FrameParticipant participant)
{
Object[] nparts = ListUtil.testAndAddRef(_participants, participant);
if (nparts == null) {
Log.warning("Refusing to add duplicate frame participant! " + participant);
} else {
_participants = nparts;
}
}
/**
* Returns true if the specified participant is registered.
*/
public boolean isRegisteredFrameParticipant (FrameParticipant participant)
{
return ListUtil.containsRef(_participants, participant);
}
/**
* Removes a frame participant.
*/
public void removeFrameParticipant (FrameParticipant participant)
{
ListUtil.clearRef(_participants, participant);
}
/**
* Returns a millisecond granularity time stamp using the {@link MediaTimer} with which this
* frame manager was configured. Note: this should only be called from the AWT
* thread.
*/
public long getTimeStamp ()
{
return _timer.getElapsedMillis();
}
/**
* Returns an overlay that can be used to render sprites and animations on top of the entire
* frame. This is lazily created the first time this method is called and the overlay will
* remain a frame participant until {@link #clearMediaOverlay} is called. Be sure to coordinate
* access to the overlay in your application as there is only one overlay in existence at any
* time, and attempts to use an overlay after it has been cleared will fail.
*/
public MediaOverlay getMediaOverlay ()
{
if (_overlay == null) {
_overlay = new MediaOverlay(this);
registerFrameParticipant(_overlay);
}
return _overlay;
}
/**
* Clears out any media overlay that is in use.
*/
public void clearMediaOverlay ()
{
if (_overlay != null) {
removeFrameParticipant(_overlay);
_overlay = null;
}
}
/**
* Starts up the per-frame tick
*/
public void start ()
{
if (_ticker == null) {
_ticker = new Ticker();
_ticker.start();
_lastTickStamp = 0;
}
}
/**
* Stops the per-frame tick.
*/
public synchronized void stop ()
{
if (_ticker != null) {
_ticker.cancel();
_ticker = null;
}
}
/**
* Returns true if the tick interval is be running (not necessarily at that instant, but in
* general).
*/
public synchronized boolean isRunning ()
{
return (_ticker != null);
}
/**
* Returns the number of ticks executed in the last second.
*/
public int getPerfTicks ()
{
return Math.round(_fps[1]);
}
/**
* Returns the number of ticks requested in the last second.
*/
public int getPerfTries ()
{
return Math.round(_fps[0]);
}
/**
* Returns debug performance metrics.
*/
public TrailingAverage[] getPerfMetrics ()
{
if (_metrics == null) {
_metrics = new TrailingAverage[] {
new TrailingAverage(150), new TrailingAverage(150), new TrailingAverage(150)
};
}
return _metrics;
}
/**
* Returns the root component for the supplied component or null if it is not part of a rooted
* hierarchy or if any parent along the way is found to be hidden or without a peer. Along the
* way, it adjusts the supplied component-relative rectangle to be relative to the returned
* root component.
*/
public static Component getRoot (Component comp, Rectangle rect)
{
for (Component c = comp; c != null; c = c.getParent()) {
if (!c.isVisible() || !c.isDisplayable()) {
return null;
}
if (c instanceof Window || c instanceof Applet) {
return c;
}
rect.x += c.getX();
rect.y += c.getY();
}
return null;
}
/**
* Initializes this frame manager and prepares it for operation.
*/
protected void init (ManagedRoot root, MediaTimer timer)
{
_window = root.getWindow();
_root = root;
_root.init(this);
_timer = timer;
// set up our custom repaint manager
_remgr = new ActiveRepaintManager(_window);
RepaintManager.setCurrentManager(_remgr);
// turn off double buffering for the whole business because we handle repaints
_remgr.setDoubleBufferingEnabled(false);
}
/**
* Called to perform the frame processing and rendering.
*/
protected void tick (long tickStamp)
{
long start = 0L, paint = 0L;
if (_perfDebug.getValue()) {
start = paint = _timer.getElapsedMicros();
}
// if our frame is not showing (or is impossibly sized), don't try rendering anything
if (_window.isShowing() && _window.getWidth() > 0 && _window.getHeight() > 0) {
// tick our participants
tickParticipants(tickStamp);
paint = _timer.getElapsedMicros();
// repaint our participants and components
paint(tickStamp);
}
if (_perfDebug.getValue()) {
long end = _timer.getElapsedMicros();
getPerfMetrics()[1].record((int)(paint-start)/100);
getPerfMetrics()[2].record((int)(end-paint)/100);
}
}
/**
* Called once per frame to invoke {@link FrameParticipant#tick} on all of our frame
* participants.
*/
protected void tickParticipants (long tickStamp)
{
long gap = tickStamp - _lastTickStamp;
if (_lastTickStamp != 0 && gap > (HANG_DEBUG ? HANG_GAP : BIG_GAP)) {
Log.debug("Long tick delay [delay=" + gap + "ms].");
}
_lastTickStamp = tickStamp;
// validate any invalid components
try {
_remgr.validateComponents();
} catch (Throwable t) {
Log.warning("Failure validating components.");
Log.logStackTrace(t);
}
// tick all of our frame participants
for (int ii = 0; ii < _participants.length; ii++) {
FrameParticipant part = (FrameParticipant)_participants[ii];
if (part == null) {
continue;
}
try {
long start = 0L;
if (HANG_DEBUG) {
start = System.currentTimeMillis();
}
part.tick(tickStamp);
if (HANG_DEBUG) {
long delay = (System.currentTimeMillis() - start);
if (delay > HANG_GAP) {
Log.info("Whoa nelly! Ticker took a long time " +
"[part=" + part + ", time=" + delay + "ms].");
}
}
} catch (Throwable t) {
Log.warning("Frame participant choked during tick " +
"[part=" + StringUtil.safeToString(part) + "].");
Log.logStackTrace(t);
}
}
}
/**
* Called once per frame to invoke {@link Component#paint} on all of our frame participants'
* components and all dirty components managed by our {@link ActiveRepaintManager}.
*/
protected abstract void paint (long tickStamp);
/**
* Returns a graphics context with which to layout its media objects. The returned context must
* be disposed when layout is complete and must not be retained across frame ticks. Used by the
* {@link MediaOverlay}.
*/
protected abstract Graphics2D createGraphics ();
/**
* Paints our frame participants and any dirty components via the repaint manager.
*
* @return true if anything was painted, false if not.
*/
protected boolean paint (Graphics2D gfx)
{
// paint our frame participants (which want to be handled specially)
int painted = 0;
for (int ii = 0; ii < _participants.length; ii++) {
FrameParticipant part = (FrameParticipant)_participants[ii];
if (part == null) {
continue;
}
Component pcomp = part.getComponent();
if (pcomp == null || !part.needsPaint()) {
continue;
}
long start = 0L;
if (HANG_DEBUG) {
start = System.currentTimeMillis();
}
// get the bounds of this component
pcomp.getBounds(_tbounds);
// the bounds adjustment we're about to call will add in the components initial bounds
// offsets, so we remove them here
_tbounds.setLocation(0, 0);
// convert them into top-level coordinates; also note that if this component does not
// have a valid or visible root, we don't want to paint it either
if (getRoot(pcomp, _tbounds) == null) {
continue;
}
try {
// render this participant; we don't set the clip because frame participants are
// expected to handle clipping themselves; otherwise we might pointlessly set the
// clip here, creating a few Rectangle objects in the process, only to have the
// frame participant immediately set the clip to something more sensible
gfx.translate(_tbounds.x, _tbounds.y);
pcomp.paint(gfx);
gfx.translate(-_tbounds.x, -_tbounds.y);
painted++;
} catch (Throwable t) {
String ptos = StringUtil.safeToString(part);
Log.warning("Frame participant choked during paint [part=" + ptos + "].");
Log.logStackTrace(t);
}
// render any components in our layered pane that are not in the default layer
_clipped[0] = false;
renderLayers(gfx, pcomp, _tbounds, _clipped);
if (HANG_DEBUG) {
long delay = (System.currentTimeMillis() - start);
if (delay > HANG_GAP) {
Log.warning("Whoa nelly! Painter took a long time " +
"[part=" + part + ", time=" + delay + "ms].");
}
}
}
// repaint any widgets that have declared they need to be repainted since the last tick
boolean pcomp = _remgr.paintComponents(gfx, this);
// let the caller know if anybody painted anything
return ((painted > 0) || pcomp);
}
/**
* Called by the {@link ManagedJFrame} when our window was hidden and reexposed.
*/
protected abstract void restoreFromBack (Rectangle dirty);
/**
* Renders all components in all {@link JLayeredPane} layers that intersect the supplied
* bounds.
*/
protected void renderLayers (Graphics2D g, Component pcomp,
Rectangle bounds, boolean[] clipped)
{
JLayeredPane lpane = JLayeredPane.getLayeredPaneAbove(pcomp);
if (lpane != null) {
renderLayer(g, bounds, lpane, clipped, JLayeredPane.PALETTE_LAYER);
renderLayer(g, bounds, lpane, clipped, JLayeredPane.MODAL_LAYER);
renderLayer(g, bounds, lpane, clipped, JLayeredPane.POPUP_LAYER);
renderLayer(g, bounds, lpane, clipped, JLayeredPane.DRAG_LAYER);
}
}
/**
* Renders all components in the specified layer of the supplied layered pane that intersect
* the supplied bounds.
*/
protected void renderLayer (Graphics2D g, Rectangle bounds, JLayeredPane pane,
boolean[] clipped, Integer layer)
{
// stop now if there are no components in that layer
int ccount = pane.getComponentCountInLayer(layer.intValue());
if (ccount == 0) {
return;
}
// render them up
Component[] comps = pane.getComponentsInLayer(layer.intValue());
for (int ii = 0; ii < ccount; ii++) {
Component comp = comps[ii];
if (!comp.isVisible() || comp instanceof SafeLayerComponent) {
continue;
}
// if this overlay does not intersect the component we just rendered, we don't need to
// repaint it
_tbounds.setBounds(0, 0, comp.getWidth(), comp.getHeight());
getRoot(comp, _tbounds);
if (!_tbounds.intersects(bounds)) {
continue;
}
// if the clipping region has not yet been set during this render pass, the time has
// come to do so
if (!clipped[0]) {
g.setClip(bounds);
clipped[0] = true;
}
// translate into the components coordinate system and render
g.translate(_tbounds.x, _tbounds.y);
try {
comp.paint(g);
} catch (Exception e) {
Log.warning("Component choked while rendering.");
Log.logStackTrace(e);
}
g.translate(-_tbounds.x, -_tbounds.y);
}
}
/** Used to effect periodic calls to {@link #tick}. */
protected class Ticker extends Thread
{
public void run ()
{
Log.info("Frame manager ticker running " +
"[sleepGran=" + _sleepGranularity.getValue() + "].");
while (_running) {
long start = 0L;
if (_perfDebug.getValue()) {
start = _timer.getElapsedMicros();
}
Unsafe.sleep(_sleepGranularity.getValue());
long woke = _timer.getElapsedMicros();
if (start > 0L) {
getPerfMetrics()[0].record((int)(woke-start)/100);
int elapsed = (int)(woke-start);
if (elapsed > _sleepGranularity.getValue()*1500) {
Log.warning("Long tick [elapsed=" + elapsed + "us].");
}
}
// work around sketchy bug on WinXP that causes the clock to leap into the past
// from time to time
if (woke < _lastAttempt) {
Log.warning("Zoiks! We've leapt into the past, coping as best we can " +
"[dt=" + (woke - _lastAttempt) + "].");
_lastAttempt = woke;
}
if (woke - _lastAttempt >= _millisPerFrame * 1000) {
_lastAttempt = woke;
if (testAndSet()) {
EventQueue.invokeLater(_awtTicker);
}
// else: drop the frame
}
}
}
public void cancel ()
{
_running = false;
}
protected final synchronized boolean testAndSet ()
{
_tries++;
if (!_ticking) {
_ticking = true;
return true;
}
return false;
}
protected final synchronized void clearTicking (long elapsed)
{
if (++_ticks == 100) {
long time = (elapsed - _lastTick);
_fps[0] = _tries * 1000f / time;
_fps[1] = _ticks * 1000f / time;
_lastTick = elapsed;
_ticks = _tries = 0;
}
_ticking = false;
}
/** Used to invoke the call to {@link #tick} on the AWT event queue thread. */
protected Runnable _awtTicker = new Runnable () {
public void run () {
long elapsed = _timer.getElapsedMillis();
try {
tick(elapsed);
} finally {
clearTicking(elapsed);
}
}
};
/** Used to stick a fork in our ticker when desired. */
protected transient boolean _running = true;
/** Used to detect when we need to drop frames. */
protected boolean _ticking;
/** The time at which we last attempted to tick. */
protected long _lastAttempt;
/** Used to compute metrics. */
protected int _tries, _ticks, _time;
/** Used to compute metrics. */
protected long _lastTick;
};
/** The window into which we do our rendering. */
protected Window _window;
/** Provides access to our Swing bits. */
protected ManagedRoot _root;
/** Used to obtain timing measurements. */
protected MediaTimer _timer;
/** Our custom repaint manager. */
protected ActiveRepaintManager _remgr;
/** If active, an overlay that will be rendering sprites and animations on top of the frame. */
protected MediaOverlay _overlay;
/** The number of milliseconds per frame (14 by default, which gives an fps of ~71). */
protected long _millisPerFrame = 14;
/** Used to track big delays in calls to our tick method. */
protected long _lastTickStamp;
/** The thread that dispatches our frame ticks. */
protected Ticker _ticker;
/** Used to track and report frames per second. */
protected float[] _fps = new float[2];
/** Used to track performance metrics. */
protected TrailingAverage[] _metrics;
/** A temporary bounds rectangle used to avoid lots of object creation. */
protected Rectangle _tbounds = new Rectangle();
/** Used to lazily set the clip when painting popups and other "layered" components. */
protected boolean[] _clipped = new boolean[1];
/** The entites that are ticked each frame. */
protected Object[] _participants = new Object[4];
/** If we don't get ticked for 500ms, that's worth complaining about. */
protected static final long BIG_GAP = 500L;
/** If we don't get ticked for 100ms and we're hang debugging, complain. */
protected static final long HANG_GAP = 100L;
/** Enable this to log warnings when ticking or painting takes too long. */
protected static final boolean HANG_DEBUG = false;
/** A debug hook that toggles debug rendering of sprite paths. */
protected static RuntimeAdjust.BooleanAdjust _useFlip = new RuntimeAdjust.BooleanAdjust(
"When active a flip-buffer will be used to manage our rendering, otherwise a " +
"volatile back buffer is used [requires restart]", "narya.media.frame",
// back buffer rendering doesn't work on the Mac, so we default to flip buffer on that
// platform; we still allow it to be toggled so that we can easily test things when
// they release new JVMs
MediaPrefs.config, RunAnywhere.isMacOS());
/** Allows us to tweak the sleep granularity. */
protected static RuntimeAdjust.IntAdjust _sleepGranularity = new RuntimeAdjust.IntAdjust(
"The number of milliseconds slept before checking to see if it's time to queue up a " +
"new frame tick.", "narya.media.sleep_gran",
MediaPrefs.config, RunAnywhere.isWindows() ? 10 : 7);
/** A debug hook that toggles FPS rendering. */
protected static RuntimeAdjust.BooleanAdjust _perfDebug = new RuntimeAdjust.BooleanAdjust(
"Toggles frames per second and dirty regions per tick rendering.",
"narya.media.fps_display", MediaPrefs.config, false);
/** The name of the high-performance timer class we attempt to load. */
protected static final String PERF_TIMER = "com.threerings.media.timer.PerfTimer";
}