Implementation of NSAnimation and NSViewAnimation classes :

- only NSAnimationNonBlocking mode is implemented
- runLoopModesForAnimating is not used
GSAnimator class is in alpha stage : interface may be changed


git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/trunk@24968 72102866-910b-0410-8b05-ffd578937521

Headers/Additions/GNUstepGUI/GSAnimator.h

@@ -0,0 +1,123 @@
+/*
+ * GSAnimator.h
+ *
+ * Author: Xavier Glattard (xgl) <xavier.glattard@online.fr>
+ *
+ * Copyright (c) 2007 Free Software Foundation, Inc.
+ *
+ * This file used to be part of the mySTEP Library.
+ * This file now is part of the GNUstep GUI Library.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; see the file COPYING.LIB.
+ * If not, write to the Free Software Foundation,
+ * 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */ 
+
+#ifndef _GNUstep_H_GSAnimator_
+#define _GNUstep_H_GSAnimator_
+
+@class NSRunLoop;
+@class NSEvent;
+@class NSTimer;
+@class NSThread;
+
+#include <Foundation/NSObject.h>
+#include <Foundation/NSDate.h>
+#include <Foundation/NSTimer.h>
+
+/**
+ * Protocol that needs to be adopted by classes that want to
+ * be animated by a GSAnimator.
+ */
+@protocol GSAnimation
+/** Returns the run-loop modes useed to run the animation timer in. */
+- (NSArray*) runLoopModesForAnimating;
+/** Call back method indicating that the GSAnimator did start the
+ * animation loop. */
+- (void) animatorDidStart;
+/** Call back method indicating that the GSAnimator did stop the
+ * animation loop. */
+- (void) animatorDidStop;
+/** Call back method called for each animation loop. */
+- (void) animatorStep: (NSTimeInterval) elapsedTime;
+@end
+
+typedef enum
+{
+  GSTimerBasedAnimation,
+  GSPerformerBasedAnimation,
+  // Cocoa compatible animation modes :
+  GSBlockingCocoaAnimation,
+  GSNonblockingCocoaAnimation,
+  GSNonblockingCocoaThreadedAnimation
+} GSAnimationBlockingMode;
+
+/**
+ * GSAnimator is the front of a class cluster. Instances of a subclass of 
+ * GSAnimator manages the timing of an animation.
+ */
+@interface GSAnimator : NSObject
+{
+  id<GSAnimation> _animation; // The Object to be animated
+  NSDate *_startTime;         // The time the animation did started
+  BOOL _running;              // Indicates that the animator is looping
+
+  NSTimeInterval _elapsed;    // Elapsed time since the animator started
+  NSTimeInterval _lastFrame;  // The time of the last animation loop
+  unsigned int _frameCount;   // The number of loops since the start
+
+  NSRunLoop *_runLoop;        // The run-loop used for looping
+  
+  NSTimer *_timer;            // Timer used for looping
+  NSTimeInterval _timerInterval;
+}
+
+/** Returns a GSAnimator object initialized with the specified object
+ * to be animated. */
++ (GSAnimator*) animatorWithAnimation: (id<GSAnimation>)anAnimation
+                                 mode: (GSAnimationBlockingMode)aMode
+                            frameRate: (float)fps;
+
+/** Returns a GSAnimator object allocated in the given NSZone and 
+ * initialized with the specified object to be animated. */
++ (GSAnimator*) animatorWithAnimation: (id<GSAnimation>)anAnimation
+                                 mode: (GSAnimationBlockingMode)aMode
+                            frameRate: (float)fps
+			         zone: (NSZone*)aZone;
+
+/** Returns a GSAnimator object initialized with the specified object
+ * to be animated. */
+- (GSAnimator*) initWithAnimation: (id<GSAnimation>)anAnimation
+                        frameRate: (float)aFrameRate
+                          runLoop: (NSRunLoop*)aRunLoop;
+- (GSAnimator*) initWithAnimation: (id<GSAnimation>)anAnimation;
+
+- (unsigned int) frameCount;
+- (void) resetCounters;
+- (float) frameRate;
+- (NSRunLoop*) runLoopForAnimating;
+- (NSArray*) runLoopModesForAnimating;
+
+- (void) startAnimation;
+- (void) stopAnimation;
+- (BOOL) isAnimationRunning;
+- (void) startStopAnimation;
+
+- (void) stepAnimation;
+
+- (void) animationLoopEvent: (NSEvent*)e;
+@end
+
+#endif /* _GNUstep_H_GSAnimator_ */

Headers/AppKit/AppKit.h

@@ -45,6 +45,7 @@
 #include <AppKit/NSGraphics.h>
 
 #include <AppKit/NSActionCell.h>
+#include <AppKit/NSAnimation.h>
 #include <AppKit/NSApplication.h>
 #include <AppKit/NSAttributedString.h>
 #include <AppKit/NSBitmapImageRep.h>

Headers/AppKit/NSAnimation.h

@@ -2,7 +2,9 @@
  * NSAnimation.h
  *
  * Created by Dr. H. Nikolaus Schaller on Sat Jan 07 2006.
- * Copyright (c) 2005 DSITRI.
+ * Copyright (c) 2007 Free Software Foundation, Inc.
+ *
+ * Author: Xavier Glattard (xgl) <xavier.glattard@online.fr>
  *
  * This file used to be part of the mySTEP Library.
  * This file now is part of the GNUstep GUI Library.
@@ -24,106 +26,339 @@
  * Boston, MA 02110-1301, USA.
  */ 
 
-#ifndef _NSAnimation_h_GNUstep_
+#ifndef _GNUstep_H_NSAnimation_
-#define _NSAnimation_h_GNUstep_
+#define _GNUstep_H_NSAnimation_
 
-#include <Foundation/Foundation.h>
+#include <GNUstepBase/GSVersionMacros.h>
 
+#if OS_API_VERSION(MAC_OS_X_VERSION_10_4, GS_API_LATEST)
+
+#include <Foundation/NSObject.h>
+#include <AppKit/AppKitDefines.h>
+#include <GNUstepGUI/GSAnimator.h>
+#include <Foundation/NSString.h>
+#include <Foundation/NSArray.h>
+
+// Bezier curve parameters
+typedef struct __GSBezierDesc
+{
+  float p[4]; // control points
+  BOOL areCoefficientsComputed;
+  float a[4]; // coefficients
+} _GSBezierDesc;
+
+static inline void 
+_GSBezierComputeCoefficients( _GSBezierDesc *b )
+{
+  b->a[0] =     b->p[0];
+  b->a[1] =-3.0*b->p[0]+3.0*b->p[1];
+  b->a[2] = 3.0*b->p[0]-6.0*b->p[1]+3.0*b->p[2];
+  b->a[3] =-    b->p[0]+3.0*b->p[1]-3.0*b->p[2]+b->p[3];
+  b->areCoefficientsComputed = YES;
+}
+
+static inline float 
+_GSBezierEval( _GSBezierDesc *b, float t )
+{
+  if(!b->areCoefficientsComputed)
+    _GSBezierComputeCoefficients(b);
+  return b->a[0]+t*(b->a[1]+t*(b->a[2]+t*b->a[3]));
+}
+
+static inline float 
+_GSBezierDerivEval( _GSBezierDesc *b, float t )
+{
+  if(!b->areCoefficientsComputed)
+    _GSBezierComputeCoefficients(b);
+  return b->a[1]+t*(2.0*b->a[2]+t*3.0*b->a[3]);
+}
+
+// Rational Bezier curve parameters
+typedef struct __GSRationalBezierDesc
+{
+  float w[4]; // weights
+  float p[4]; // control points
+  BOOL areBezierDescComputed;
+  _GSBezierDesc n; // numerator
+  _GSBezierDesc d; // denumerator
+} _GSRationalBezierDesc;
+
+static inline void 
+_GSRationalBezierComputeBezierDesc( _GSRationalBezierDesc *rb )
+{
+  unsigned i;
+  for(i=0;i<4;i++)
+    rb->n.p[i] = (rb->d.p[i] = rb->w[i]) * rb->p[i];
+  _GSBezierComputeCoefficients(&rb->n);
+  _GSBezierComputeCoefficients(&rb->d);
+  rb->areBezierDescComputed = YES;
+}
+ 
+static inline float
+_GSRationalBezierEval( _GSRationalBezierDesc *rb, float t)
+{
+  if(!rb->areBezierDescComputed)
+    _GSRationalBezierComputeBezierDesc(rb);
+  return _GSBezierEval(&(rb->n),t)/_GSBezierEval(&(rb->d),t);
+}
+
+static inline float
+_GSRationalBezierDerivEval( _GSRationalBezierDesc *rb, float t)
+{
+  if(!rb->areBezierDescComputed)
+    _GSRationalBezierComputeBezierDesc(rb);
+  float h = _GSBezierEval(&(rb->d),t);
+  return ( _GSBezierDerivEval(&(rb->n),t) * h 
+         - _GSBezierEval     (&(rb->n),t) * _GSBezierDerivEval(&(rb->d),t) )
+    / (h*h);
+}
+
+typedef struct __NSAnimationCurveDesc
+{
+  float s,e; // start & end values
+  float sg,eg; // start & end gradients 
+  _GSRationalBezierDesc rb;
+  BOOL isRBezierComputed;
+} _NSAnimationCurveDesc;
+
+extern
+_NSAnimationCurveDesc *_gs_animationCurveDesc;
+
+static inline float
+_gs_animationValueForCurve( _NSAnimationCurveDesc *c, float t, float t0 )
+{
+  if(!c->isRBezierComputed)
+  {
+    c->rb.p[0] = c->s;
+    c->rb.p[1] = c->s + (c->sg*c->rb.w[0])/(3*c->rb.w[1]);
+    c->rb.p[2] = c->e - (c->eg*c->rb.w[3])/(3*c->rb.w[2]);
+    c->rb.p[3] = c->e;
+    _GSRationalBezierComputeBezierDesc(&c->rb);
+    c->isRBezierComputed = YES;
+  }
+  return _GSRationalBezierEval( &(c->rb),(t-t0)/(1.0-t0) );
+}
+
+@class NSString;
+@class NSArray;
+@class NSNumber;
+
+/** These constants describe the curve of an animation—that is, the relative speed of an animation from start to finish. */
 typedef enum _NSAnimationCurve
 {
   NSAnimationEaseInOut = 0, // default
   NSAnimationEaseIn,
   NSAnimationEaseOut,
-  NSAnimationLinear
+  NSAnimationLinear,
+  NSAnimationSpeedInOut // GNUstep only
 } NSAnimationCurve;
 
+/** These constants indicate the blocking mode of an NSAnimation object when it is running. */
 typedef enum _NSAnimationBlockingMode
 {
-  NSAnimationBlocking,
+  NSAnimationBlocking		 = GSBlockingCocoaAnimation,
-  NSAnimationNonblocking,
+  NSAnimationNonblocking	 = GSNonblockingCocoaAnimation,
-  NSAnimationNonblockingThreaded
+  NSAnimationNonblockingThreaded = GSNonblockingCocoaThreadedAnimation
 } NSAnimationBlockingMode;
 
 typedef float NSAnimationProgress;
 
-extern NSString *NSAnimationProgressMarkNotification;
+/** Posted when the current progress of a running animation reaches one of its progress marks. */
+APPKIT_EXPORT NSString *NSAnimationProgressMarkNotification;
 
-@interface NSAnimation : NSObject < NSCopying, NSCoding >
+/**
+ * Objects of the NSAnimation class manage the timing and progress of
+ * animations in the user interface. The class also lets you link together
+ * multiple animations so that when one animation ends another one starts.
+ * It does not provide any drawing support for animation and does not directly
+ * deal with views, targets, or actions.
+ */
+@interface NSAnimation : NSObject < NSCopying, NSCoding, GSAnimation >
 {
-  NSAnimationBlockingMode _animationBlockingMode;
+  NSTimeInterval _duration;		  // Duration of the animation
-  NSAnimationCurve _animationCurve;
+  float _frameRate;			  // Wanted frame rate
-  NSAnimationProgress _currentProgress;
+  NSAnimationCurve _curve;		  // Id of progres->value function
-  NSMutableArray *_progressMarks;
+  _NSAnimationCurveDesc _curveDesc;       // The curve as a rat. Bezier
-  id _delegate;
+  NSAnimationProgress _curveProgressShift;// Shift used for switching
-  NSTimeInterval _duration;
+					  //   from a curve to an other
-  float _currentValue;
+  NSAnimationProgress _currentProgress;   // Progress of the animation
-  float _frameRate;
+
-  BOOL _isAnimating; // ?or the NSThread *
+  /* GSIArray<NSAnimationProgress> */ void *_progressMarks; // Array
+  unsigned int _nextMark;                 // The next mark to be reached
+                                          //   = count if no next mark
+  NSNumber **_cachedProgressMarkNumbers;  // Cached values used by
+  unsigned _cachedProgressMarkNumberCount;//   [-progressMarks]
+  BOOL _isCachedProgressMarkNumbersValid;
+
+  NSAnimation *_startAnimation, *_stopAnimation; // Animations used as
+  NSAnimationProgress _startMark, _stopMark;     // trigger, and marks
+
+  NSAnimationBlockingMode _blockingMode;  // Blocking mode
+  GSAnimator *_animator;                  // The animator
+  BOOL _isANewAnimatorNeeded;              // Some parameters have changed...
+
+  id _delegate; // The delegate, and the cached delegation methods...
+  void  (*_delegate_animationDidReachProgressMark)(id,SEL,NSAnimation*,NSAnimationProgress);
+  float (*_delegate_animationValueForProgress    )(id,SEL,NSAnimation*,NSAnimationProgress);
+  void  (*_delegate_animationDidEnd              )(id,SEL,NSAnimation*);
+  void  (*_delegate_animationDidStop             )(id,SEL,NSAnimation*);
+  BOOL  (*_delegate_animationShouldStart         )(id,SEL,NSAnimation*);
 }
 
-- (void) addProgressMark: (NSAnimationProgress) progress;
+/** Adds the progress mark to the receiver. */
+- (void) addProgressMark: (NSAnimationProgress)progress;
+
+/** Returns the blocking mode the receiver is next scheduled to run under. */
 - (NSAnimationBlockingMode) animationBlockingMode;
+
+/** Returns the animation curve the receiver is running under. */
 - (NSAnimationCurve) animationCurve;
+
+/** Clears linkage to another animation that causes the receiver to start. */
 - (void) clearStartAnimation;
+
+/** Clears linkage to another animation that causes the receiver to stop. */
 - (void) clearStopAnimation;
+
+/** Returns the current progress of the receiver. */
 - (NSAnimationProgress) currentProgress;
+
+/** Returns the current value of the effect based on the current progress. */
 - (float) currentValue;
+
+/** Returns the delegate of the receiver. */
 - (id) delegate;
+
+/** Returns the duration of the animation, in seconds. */
 - (NSTimeInterval) duration;
+
+/** Returns the frame rate of the animation. */
 - (float) frameRate;
-- (id) initWithDuration: (NSTimeInterval) duration animationCurve:
+
-  (NSAnimationCurve) curve;
+/** Returns an NSAnimation object initialized with the specified duration and animation-curve values. */
+- (id) initWithDuration: (NSTimeInterval)duration
+         animationCurve: (NSAnimationCurve)curve;
+
+/** Returns a Boolean value that indicates whether the receiver is currently animating. */
 - (BOOL) isAnimating;
-- (NSArray *) progressMarks;
+
-- (void) removeProgressMark: (NSAnimationProgress) progress;
+/** Returns the receiver’s progress marks. */
-- (NSArray *) runLoopModesForAnimating;
+- (NSArray*) progressMarks;
-- (void) setAnimationBlockingMode: (NSAnimationBlockingMode) mode;
+
-- (void) setAnimationCurve: (NSAnimationCurve) curve;
+/** Removes progress mark from the receiver. */
-- (void) setCurrentProgress: (NSAnimationProgress) progress;
+- (void) removeProgressMark: (NSAnimationProgress)progress;
-- (void) setDelegate: (id) delegate;
+
-- (void) setDuration: (NSTimeInterval) duration;
+/** Overridden to return the run-loop modes that the receiver uses to run the animation timer in. */
-- (void) setFrameRate: (float) fps;
+- (NSArray*) runLoopModesForAnimating;
-- (void) setProgressMarks: (NSArray *) progress;
+
+/** Sets the blocking mode of the receiver. */
+- (void) setAnimationBlockingMode: (NSAnimationBlockingMode)mode;
+
+/** Sets the receiver’s animation curve. */
+- (void) setAnimationCurve: (NSAnimationCurve)curve;
+
+/** Sets the current progress of the receiver. */
+- (void) setCurrentProgress: (NSAnimationProgress)progress;
+
+/** Sets the delegate of the receiver. */
+- (void) setDelegate: (id)delegate;
+
+/** Sets the duration of the animation to a specified number of seconds. */
+- (void) setDuration: (NSTimeInterval)duration;
+
+/** Sets the frame rate of the receiver. */
+- (void) setFrameRate: (float)fps;
+
+/** Sets the receiver’s progress marks to the values specified in the passed-in array. */
+- (void) setProgressMarks: (NSArray*)progress;
+
+/** Starts the animation represented by the receiver. */
 - (void) startAnimation;
-- (void) startWhenAnimation: (NSAnimation *) animation reachesProgress:
+
-  (NSAnimationProgress) start;
+/** Starts running the animation represented by the receiver when another animation reaches a specific progress mark. */
+- (void) startWhenAnimation: (NSAnimation*)animation
+            reachesProgress: (NSAnimationProgress)start;
+
+/** Stops the animation represented by the receiver. */
 - (void) stopAnimation;
-- (void) stopWhenAnimation: (NSAnimation *) animation reachesProgress:
+
-  (NSAnimationProgress) stop;
+/** Stops running the animation represented by the receiver when another animation reaches a specific progress mark. */
+- (void) stopWhenAnimation: (NSAnimation*)animation
+           reachesProgress: (NSAnimationProgress)stop;
 
 @end
 
+@interface NSAnimation (GNUstep)
+
+/** Returns the current value of the frame counter */
+- (unsigned int) frameCount;
+
+/** Resets all stats */
+- (void) resetCounters;
+
+/** Returns the current the actual (mesured) frame rate value */
+- (float) actualFrameRate;
+
+@end
 
 @interface NSObject (NSAnimation)
 
-- (void) animation: (NSAnimation *) animation didReachProgressMark:
+/** NSAnimation delegate method.
-  (NSAnimationProgress) progress;
+ * Sent to the delegate when an animation reaches a specific progress mark. */
-- (float) animation: (NSAnimation *) animation valueForProgress:
+- (void)     animation: (NSAnimation*)animation
-  (NSAnimationProgress) progress;
+  didReachProgressMark: (NSAnimationProgress)progress;
-- (void) animationDidEnd: (NSAnimation *) animation;
+
-- (void) animationDidStop: (NSAnimation *) animation;
+/** NSAnimation delegate method.
-- (BOOL) animationShouldStart: (NSAnimation *) animation;
+ * Requests a custom curve value for the current progress value. */
+- (float) animation: (NSAnimation*)animation
+   valueForProgress: (NSAnimationProgress)progress;
+
+/** NSAnimation delegate method.
+ * Sent to the delegate when the specified animation completes its run. */
+- (void) animationDidEnd: (NSAnimation*)animation;
+
+/** NSAnimation delegate method.
+ * Sent to the delegate when the specified animation is stopped before it completes its run. */
+- (void) animationDidStop: (NSAnimation*)animation;
+
+/** NSAnimation delegate method.
+ * Sent to the delegate just after an animation is started. */
+- (BOOL) animationShouldStart: (NSAnimation*)animation;
 
 @end
 
+APPKIT_EXPORT NSString *NSViewAnimationTargetKey;
+APPKIT_EXPORT NSString *NSViewAnimationStartFrameKey;
+APPKIT_EXPORT NSString *NSViewAnimationEndFrameKey;
+APPKIT_EXPORT NSString *NSViewAnimationEffectKey;
 
-extern NSString *NSViewAnimationTargetKey;
+APPKIT_EXPORT NSString *NSViewAnimationFadeInEffect;
-extern NSString *NSViewAnimationStartFrameKey;
+APPKIT_EXPORT NSString *NSViewAnimationFadeOutEffect;
-extern NSString *NSViewAnimationEndFrameKey;
-extern NSString *NSViewAnimationEffectKey;
-extern NSString *NSViewAnimationFadeInEffect;
-extern NSString *NSViewAnimationFadeOutEffect;
 
+/**
+ * The NSViewAnimation class, a public subclass of NSAnimation,
+ * offers a convenient way to animate multiple views and windows.
+ * The animation effects you can achieve are limited to changes in
+ * frame location and size, and to fade-in and fade-out effects.
+ */
 @interface NSViewAnimation : NSAnimation
 {
   NSArray *_viewAnimations;
+  NSMutableArray *_viewAnimationDesc;
 }
 
-- (id) initWithViewAnimations: (NSArray *) animations;
+/** Returns an NSViewAnimation object initialized with the supplied information. */
-- (void) setWithViewAnimations: (NSArray *) animations;
+- (id) initWithViewAnimations: (NSArray*)animations;
-- (NSArray *) viewAnimations;
+
+/** Sets the dictionaries defining the objects to animate. */
+- (void) setViewAnimations: (NSArray*)animations;
+
+/** Returns the array of dictionaries defining the objects to animate. */
+- (NSArray*) viewAnimations;
 
 @end
 
-#endif /* _NSAnimation_h_GNUstep_ */
+#endif /* OS_API_VERSION */
+
+#endif /* _GNUstep_H_NSAnimation_ */
 

Source/GNUmakefile

@@ -170,6 +170,7 @@ NSWindow+Toolbar.m \
 NSWindow.m \
 NSWindowController.m \
 NSWorkspace.m \
+GSAnimator.m \
 GSDisplayServer.m \
 GSFusedSilica.m \
 GSFusedSilicaContext.m \
@@ -368,6 +369,7 @@ GUI_HEADERS = \
 GSVersion.h \
 GMAppKit.h \
 GMArchiver.h \
+GSAnimator.h \
 GSTheme.h \
 GSFontInfo.h \
 GSMemoryPanel.h \

Source/GSAnimator.m

@@ -0,0 +1,359 @@
+/*
+ * GSAnimator.m
+ *
+ * Author: Xavier Glattard (xgl) <xavier.glattard@online.fr>
+ *
+ * Copyright (c) 2007 Free Software Foundation, Inc.
+ *
+ * This file used to be part of the mySTEP Library.
+ * This file now is part of the GNUstep GUI Library.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; see the file COPYING.LIB.
+ * If not, write to the Free Software Foundation,
+ * 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */ 
+
+#include <GNUstepGUI/GSAnimator.h>
+
+#include <Foundation/NSTimer.h>
+#include <Foundation/NSRunLoop.h>
+#include <Foundation/NSThread.h>
+#include <Foundation/NSString.h>
+#include <Foundation/NSSet.h>
+#include <Foundation/NSNotification.h>
+
+#include <AppKit/NSEvent.h>
+
+typedef enum {
+  NullEvent,
+  GSAnimationNextFrameEvent,
+  GSAnimationEventTypeNumber
+} GSAnimationEventType;
+
+@interface GSAnimator(private)
+- (void) _animationBegin;
+- (void) _animationLoop;
+- (void) _animationEnd;
+@end
+
+@interface GSTimerBasedAnimator : GSAnimator
+{ }
+@end
+
+@interface GSPerformerBasedAnimator : GSAnimator
+{ }
+@end
+
+@interface GSThreadedTimerBasedAnimator : GSAnimator
+{
+  NSThread* _thread;
+}
+@end
+
+@implementation GSAnimator
+
++ (GSAnimator*) animatorWithAnimation: (id<GSAnimation>)anAnimation
+                                 mode: (GSAnimationBlockingMode)aMode
+                            frameRate: (float)fps
+{ 
+  return [self 
+    animatorWithAnimation: anAnimation
+		     mode: aMode
+		frameRate: fps
+		     zone: NULL];
+}
+
++ (GSAnimator*) animatorWithAnimation: (id<GSAnimation>)anAnimation
+                                 mode: (GSAnimationBlockingMode)aMode
+                            frameRate: (float)fps
+			         zone: (NSZone*)aZone
+{
+  GSAnimator* animator;
+  NSRunLoop* runLoop;
+
+  switch(aMode)
+  {//FIXME
+    case GSTimerBasedAnimation:
+    case GSPerformerBasedAnimation:
+    case GSBlockingCocoaAnimation:
+    case GSNonblockingCocoaAnimation:
+    case GSNonblockingCocoaThreadedAnimation:
+      runLoop = [NSRunLoop currentRunLoop];
+      animator = [[GSTimerBasedAnimator allocWithZone: aZone]
+	initWithAnimation: anAnimation
+	    	frameRate: fps
+		  runLoop: runLoop];
+  }
+  AUTORELEASE(animator);
+  return animator;
+}
+
+- (GSAnimator*) initWithAnimation: (id<GSAnimation>)anAnimation
+			frameRate: (float)aFrameRate
+			  runLoop: (NSRunLoop*)aRunLoop
+{
+  if((self = [super init]))
+  {
+    _running = NO;
+    
+    _animation = anAnimation; TEST_RETAIN(_animation);
+    _runLoop = aRunLoop; TEST_RETAIN(_runLoop);
+    _timerInterval = (aFrameRate==0.0)?0.0:(1.0/aFrameRate);
+
+    [self resetCounters];
+  }
+  return self;
+}
+
+- (GSAnimator*) initWithAnimation: (id<GSAnimation>)anAnimation
+{
+  return [self initWithAnimation: anAnimation
+		       frameRate: 0.0
+			 runLoop: [NSRunLoop currentRunLoop]];
+}
+
+- (void) dealloc
+{
+  [self stopAnimation];
+  TEST_RELEASE(_animation);
+  TEST_RELEASE(_runLoop);
+  TEST_RELEASE(_startTime);
+  [super dealloc];
+}
+
+- (unsigned int) frameCount
+{ return _frameCount; }
+
+- (void) resetCounters
+{
+  _elapsed = 0.0;
+  _frameCount = 0;
+  _lastFrame = [NSDate timeIntervalSinceReferenceDate];
+}
+
+- (float) frameRate 
+{ return ((float)[self frameCount]) / ((float)_elapsed); }
+
+- (NSRunLoop*) runLoopForAnimating
+{ return _runLoop; }
+
+- (NSArray*) runLoopModesForAnimating
+{ return [_animation runLoopModesForAnimating]; }
+
+- (void) startAnimation
+{
+  if(!_running)
+  {
+    _running = YES;
+    [self resetCounters];
+    [_animation animatorDidStart];
+    [self _animationBegin];
+    [self _animationLoop];
+  }
+}
+
+- (void) stopAnimation
+{
+  if(_running)
+  {
+    _running = NO;
+    [self _animationEnd];
+    [_animation animatorDidStop];
+  }
+}
+
+- (void) startStopAnimation
+{
+  if(_running)
+    [self stopAnimation];
+  else
+    [self startAnimation];
+}
+
+- (BOOL) isAnimationRunning
+{ return _running; }
+
+- (void) _animationBegin
+{ [self subclassResponsibility: _cmd]; }
+
+- (void) _animationLoop
+{ [self subclassResponsibility: _cmd]; }
+
+- (void) _animationEnd
+{ [self subclassResponsibility: _cmd]; }
+
+- (void) stepAnimation
+{
+  NSTimeInterval thisFrame = [NSDate timeIntervalSinceReferenceDate];
+  NSTimeInterval sinceLastFrame = (thisFrame - _lastFrame);
+  _elapsed += sinceLastFrame;
+  _lastFrame = thisFrame;
+
+  [_animation animatorStep: _elapsed];
+  _frameCount++;
+}
+
+- (void) animationLoopEvent: (NSEvent*) e
+{ [self subclassResponsibility: _cmd]; }
+
+@end
+
+static NSTimer* _GSTimerBasedAnimator_timer = nil;
+static NSMutableSet* _GSTimerBasedAnimator_animators = nil;
+static GSTimerBasedAnimator* _GSTimerBasedAnimator_the_one_animator = nil;
+static int _GSTimerBasedAnimator_animator_count = 0;
+
+@implementation GSTimerBasedAnimator
+
++ (void) loopsAnimators
+{
+  switch(_GSTimerBasedAnimator_animator_count)
+  {
+    case 0:
+      break;
+    case 1:
+      [_GSTimerBasedAnimator_the_one_animator _animationLoop];
+      break;
+    default:
+      [[NSNotificationCenter defaultCenter]
+        postNotificationName: @"GSTimerBasedAnimator_loop" object: self];
+  }
+}
+
++ (void) registerAnimator: (GSTimerBasedAnimator*) anAnimator
+{
+  if(anAnimator->_timerInterval == 0.0)
+  {
+    [[NSNotificationCenter defaultCenter]
+      addObserver: anAnimator
+	 selector: @selector(_animationLoop)
+	     name: @"GSTimerBasedAnimator_loop"
+	   object: self];
+  
+    if(!_GSTimerBasedAnimator_animator_count++)
+      _GSTimerBasedAnimator_the_one_animator = anAnimator;
+
+    if(nil==_GSTimerBasedAnimator_animators)
+      _GSTimerBasedAnimator_animators = [[NSMutableSet alloc] initWithCapacity: 5];
+    [_GSTimerBasedAnimator_animators addObject: anAnimator];
+  
+    if(nil==_GSTimerBasedAnimator_timer)
+    {
+      _GSTimerBasedAnimator_timer = [NSTimer
+	scheduledTimerWithTimeInterval: 0.0
+	   			target: self
+	     		      selector: @selector(loopsAnimators)
+	       		      userInfo: nil
+		 	       repeats: YES
+			       ];
+      TEST_RETAIN(_GSTimerBasedAnimator_timer);
+    }
+  }
+  else
+  {
+    anAnimator->_timer = [NSTimer
+      scheduledTimerWithTimeInterval: anAnimator->_timerInterval
+			      target: anAnimator
+			    selector: @selector(_animationLoop)
+			    userInfo: nil
+			     repeats: YES
+			     ];
+    TEST_RETAIN(anAnimator->_timer);
+  }
+}
+
++ (void) unregisterAnimator: (GSTimerBasedAnimator*) anAnimator
+{
+  if(anAnimator->_timerInterval == 0.0)
+  {
+    [[NSNotificationCenter defaultCenter]
+      removeObserver: anAnimator
+		name: @"GSTimerBasedAnimator_loop"
+	      object: self];
+
+    [_GSTimerBasedAnimator_animators removeObject: anAnimator];
+      
+    if(!--_GSTimerBasedAnimator_animator_count)
+    {
+      [_GSTimerBasedAnimator_timer invalidate];
+      DESTROY(_GSTimerBasedAnimator_timer);
+      _GSTimerBasedAnimator_the_one_animator = nil;
+    }
+    else
+      if(_GSTimerBasedAnimator_the_one_animator==anAnimator)
+	_GSTimerBasedAnimator_the_one_animator
+	  = [_GSTimerBasedAnimator_animators anyObject];
+  }
+  else
+  {
+    if(anAnimator->_timer != nil)
+    {
+      [anAnimator->_timer invalidate];
+      DESTROY(anAnimator->_timer);
+    }
+  }
+}
+
+- (void) _animationBegin
+{
+  [[self class] registerAnimator: self];
+}
+
+- (void) _animationLoop
+{
+  [self stepAnimation];
+}
+
+- (void) _animationEnd
+{
+  [[self class] unregisterAnimator: self];
+}
+
+@end
+
+static void _sendAnimationPerformer( GSAnimator* animator )
+{
+  [[animator runLoopForAnimating]
+    performSelector: @selector(_animationLoop)
+       	     target: animator
+	   argument: nil
+	      order: 1000000
+	      modes: [animator runLoopModesForAnimating]
+  ];
+}
+
+static void _cancelAnimationPerformer( GSAnimator* animator )
+{
+  [[animator runLoopForAnimating] cancelPerformSelectorsWithTarget: animator];
+}
+
+@implementation GSPerformerBasedAnimator
+
+- (void) _animationBegin
+{ [self _animationLoop]; }
+
+- (void) _animationLoop
+{
+  [self stepAnimation];
+  if(_running)
+    _sendAnimationPerformer(self);
+}
+
+- (void) _animationEnd
+{ _cancelAnimationPerformer(self); }
+
+@end
+
+