Added ability to render animations in two distinct layers; added mechanism

whereby animations can clean up after themselves.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@1130 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/animation/Animation.java

@@ -1,5 +1,5 @@
 //
-// $Id: Animation.java,v 1.3 2002/03/14 21:09:01 shaper Exp $
+// $Id: Animation.java,v 1.4 2002/03/16 03:11:23 shaper Exp $
 
 package com.threerings.media.animation;
 
@@ -27,6 +27,25 @@ public abstract class Animation
         _bounds = bounds;
     }
 
+    /**
+     * Returns the render order of this animation.
+     */
+    public int getRenderOrder ()
+    {
+        return _renderOrder;
+    }
+
+    /**
+     * Sets the render order associated with this animation.  Animations
+     * can be rendered in two layers; those with negative render order and
+     * those with positive render order.  Someday animations will be
+     * rendered in each layer according to render order.
+     */
+    public void setRenderOrder (int value)
+    {
+        _renderOrder = value;
+    }
+
     /**
      * Called by the {@link AnimationManager} to allow the animation to
      * render itself to the given graphics context.
@@ -65,6 +84,15 @@ public abstract class Animation
         return _finished;
     }
 
+    /**
+     * Called when the animation is finished and the animation manager has
+     * removed it from service.
+     */
+    protected void didFinish ()
+    {
+        // nothing for now
+    }
+
     /**
      * Adds an animation observer to this animation's list of observers.
      */
@@ -137,6 +165,9 @@ public abstract class Animation
     /** The animation bounds. */
     protected Rectangle _bounds;
 
+    /** The render order of this animation. */
+    protected int _renderOrder;
+
     /** The list of animation observers. */
     protected ArrayList _observers;
 

src/java/com/threerings/media/animation/AnimationManager.java

@@ -1,5 +1,5 @@
 //
-// $Id: AnimationManager.java,v 1.7 2002/02/19 01:23:56 mdb Exp $
+// $Id: AnimationManager.java,v 1.8 2002/03/16 03:11:23 shaper Exp $
 
 package com.threerings.media.animation;
 
@@ -30,6 +30,15 @@ import com.threerings.media.util.PerformanceObserver;
 public class AnimationManager
     implements Interval, PerformanceObserver
 {
+    /** Constant for the front layer of animations. */
+    public static final int FRONT = 0;
+
+    /** Constant for the back layer of animations. */
+    public static final int BACK = 1;
+
+    /** Constant for all layers of animations. */
+    public static final int ALL = 2;
+
     /**
      * Construct and initialize the animation manager with a sprite
      * manager and the view in which the animations will take place. The
@@ -150,14 +159,25 @@ public class AnimationManager
     }
 
     /**
-     * Renders all registered animations to the given graphics context.
+     * Renders all registered animations in the given layer to the given
+     * graphics context.
+     *
+     * @param layer the layer to render; one of {@link #FRONT}, {@link
+     * #BACK}, or {@link #ALL}.  The front layer contains all animations
+     * with a positive render order; the back layer contains all
+     * animations with a negative render order; all, both.
      */
-    public void renderAnimations (Graphics2D gfx)
+    public void renderAnimations (Graphics2D gfx, int layer)
     {
         int size = _anims.size();
         for (int ii = 0; ii < size; ii++) {
             Animation anim = (Animation)_anims.get(ii);
-            anim.paint(gfx);
+            int order = anim.getRenderOrder();
+            if ((layer == ALL) ||
+                (layer == FRONT && order >= 0) ||
+                (layer == BACK && order < 0)) {
+                anim.paint(gfx);
+            }
         }
     }
 
@@ -268,7 +288,7 @@ public class AnimationManager
 
     /**
      * The <code>tick</code> method handles updating sprites and
-     * repainting the target display.
+     * animations, and repainting the target display.
      */
     protected void tick ()
     {
@@ -343,6 +363,8 @@ public class AnimationManager
                 anim.notifyObservers(new AnimationCompletedEvent(anim));
                 // un-register the animation
                 unregisterAnimation(anim);
+                // let the animation clean itself up as necessary
+                anim.didFinish();
                 // Log.info("Removed finished animation [anim=" + anim + "].");
             }
         }

src/java/com/threerings/media/animation/SpriteAnimation.java

@@ -0,0 +1,73 @@
+//
+// $Id: SpriteAnimation.java,v 1.1 2002/03/16 03:11:23 shaper Exp $
+
+package com.threerings.media.animation;
+
+import java.awt.Graphics2D;
+import java.awt.Rectangle;
+
+import com.threerings.media.sprite.PathCompletedEvent;
+import com.threerings.media.sprite.Sprite;
+import com.threerings.media.sprite.SpriteEvent;
+import com.threerings.media.sprite.SpriteManager;
+import com.threerings.media.sprite.SpriteObserver;
+
+public class SpriteAnimation extends Animation
+    implements SpriteObserver
+{
+    /**
+     * Constructs a sprite animation for the given sprite and adds the
+     * sprite to the given sprite manager.  If the sprite has had a path
+     * set, the animation will finish when the sprite completes its path.
+     */
+    public SpriteAnimation (SpriteManager spritemgr, Sprite sprite)
+    {
+        super(new Rectangle());
+
+        // save things off
+        _spritemgr = spritemgr;
+        _sprite = sprite;
+
+        // set up our sprite business
+        _sprite.addSpriteObserver(this);
+        _spritemgr.addSprite(_sprite);
+    }
+
+    /**
+     * Derived classes can override tick if they want to end the animation
+     * in some other way than the sprite completing a path.
+     */
+    public void tick (long timestamp)
+    {
+        // nothing for now
+    }    
+
+    // documentation inherited
+    public void paint (Graphics2D gfx)
+    {
+        // nothing for now
+    }
+
+    // documentation inherited
+    public void handleEvent (SpriteEvent event)
+    {
+        if (event instanceof PathCompletedEvent) {
+            _finished = true;
+        }
+    }    
+
+    // documentation inherited
+    protected void didFinish ()
+    {
+        super.didFinish();
+
+        _spritemgr.removeSprite(_sprite);
+        _sprite = null;
+    }
+
+    /** The sprite associated with this animation. */
+    protected Sprite _sprite;
+
+    /** The sprite manager managing our sprite. */
+    protected SpriteManager _spritemgr;
+}