Created a simple straight line path, made paths actually work.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@3539 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/jme/sprite/LinePath.java

@@ -0,0 +1,60 @@
+//
+// $Id$
+//
+// Narya library - tools for developing networked games
+// Copyright (C) 2002-2005 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/narya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 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
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.jme.sprite;
+
+import com.jme.math.Vector3f;
+
+/**
+ * Moves a sprite along a straight line.
+ */
+public class LinePath extends Path
+{
+    /**
+     * Moves the supplied sprite from the starting coordinate to the
+     * specified destination coordinate in the specified time.
+     */
+    public LinePath (Sprite sprite, Vector3f start, Vector3f finish,
+                     float duration)
+    {
+        super(sprite);
+        _start = start;
+        _finish = finish;
+        _duration = duration;
+    }
+
+    // documentation inherited
+    public void update (float time)
+    {
+        _accum += time;
+        if (_accum >= _duration) {
+            _sprite.setLocalTranslation(_finish);
+            _sprite.pathCompleted();
+        } else {
+            _temp.interpolate(_start, _finish, _accum / _duration);
+            _sprite.setLocalTranslation(_temp);
+        }
+    }
+
+    protected Vector3f _start, _finish;
+    protected float _duration, _accum;
+    protected Vector3f _temp = new Vector3f(0, 0, 0);
+}

src/java/com/threerings/jme/sprite/Sprite.java

@@ -79,6 +79,7 @@ public class Sprite extends Node
 
         // save off this path
         _path = path;
+        addController(_path);
     }
 
     /**