We now copy abstract media objects to a separate array when ticking them

so that we can ensure that only tick()ed media will be painted and so that
we aren't affected by additions and removals that happen during tick().


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@2182 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/AbstractMediaManager.java

@@ -1,5 +1,5 @@
 //
-// $Id: AbstractMediaManager.java,v 1.4 2002/12/15 23:12:37 shaper Exp $
+// $Id: AbstractMediaManager.java,v 1.5 2003/01/18 03:14:29 mdb Exp $
 
 package com.threerings.media;
 
@@ -8,8 +8,10 @@ import java.awt.Rectangle;
 import java.awt.Shape;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Comparator;
 
+import com.samskivert.util.ListUtil;
 import com.samskivert.util.ObserverList;
 import com.samskivert.util.SortableArrayList;
 import com.samskivert.util.StringUtil;
@@ -48,8 +50,12 @@ public abstract class AbstractMediaManager
      */
     public void renderMedia (Graphics2D gfx, int layer, Shape clip)
     {
-        for (int ii=0, nn=_media.size(); ii < nn; ii++) {
-            AbstractMedia media = (AbstractMedia) _media.get(ii);
+        for (int ii = 0, nn = _tickvec.length; ii < nn; ii++) {
+            AbstractMedia media = _tickvec[ii];
+            if (_tickvec[ii] == null) {
+                continue;
+            }
+
             int order = media.getRenderOrder();
             try {
                 if (((layer == ALL) ||
@@ -100,10 +106,18 @@ public abstract class AbstractMediaManager
      */
     protected void tickAllMedia (long tickStamp)
     {
-        // we tick media in reverse order, because some may remove
-        // themselves on the tick
-        for (int ii=_media.size() - 1; ii >= 0; ii--) {
-            ((AbstractMedia) _media.get(ii)).tick(tickStamp);
+        // we copy our media into an array to prevent additions and
+        // removals during tick from breaking things
+        _tickvec = (AbstractMedia[])_media.toArray(_tickvec);
+
+        // clear out any leftover media
+        int mcount = _media.size();
+        if (mcount < _tickvec.length) {
+            Arrays.fill(_tickvec, mcount, _tickvec.length, null);
+        }
+
+        for (int ii = 0; ii < mcount; ii++) {
+            _tickvec[ii].tick(tickStamp);
         }
     }
 
@@ -121,11 +135,6 @@ public abstract class AbstractMediaManager
 
         _media.insertSorted(media, RENDER_ORDER);
         media.init(this);
-        if (_tickStamp > 0) {
-            // if we're in the middle of ticking, tick the inserted media
-            // so that we can paint it when the time comes
-            media.tick(_tickStamp);
-        }
         return true;
     }
 
@@ -138,6 +147,11 @@ public abstract class AbstractMediaManager
         if (_media.remove(media)) {
             media.invalidate();
             media.shutdown();
+            if (_tickStamp > 0) {
+                // if we're in the middle of ticking, clear the removed
+                // media so that we don't paint it when the time comes
+                ListUtil.clear(_tickvec, media);
+            }
             return true;
         }
         Log.warning("Attempt to remove media that wasn't inserted " +
@@ -197,6 +211,10 @@ public abstract class AbstractMediaManager
      * #tick}, else <code>0</code>. */
     protected long _tickStamp;
 
+    /** An array used to dispatch ticks and paint without worrying that
+     * additions and removals mess us up during the process. */
+    protected AbstractMedia[] _tickvec = new AbstractMedia[0];
+
     /** Used to sort media by render order. */
     protected static final Comparator RENDER_ORDER = new Comparator() {
         public int compare (Object o1, Object o2) {