Created a path for ballistic motion and an associated test. Yay for

physics. git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@3610 542714f4-19e9-0310-aa3c-eee0fc999fb1
2005-06-22 18:26:54 +00:00
parent 264d0e65d5
commit 6fbdc4e568
2 changed files with 149 additions and 0 deletions
@@ -0,0 +1,68 @@
+//
+// $Id$
+//
+// 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 ballistically.
+ */
+public class BallisticPath extends Path
+{
+    /**
+     * Moves the supplied sprite from the starting coordinate (which will
+     * be modified) using the starting velocity, under the specified
+     * acceleration.
+     */
+    public BallisticPath (Sprite sprite, Vector3f start, Vector3f velocity,
+                          Vector3f accel, float duration)
+    {
+        super(sprite);
+        _curpos = start;
+        _velocity = velocity;
+        _accel = accel;
+        _duration = duration;
+    }
+
+    // documentation inherited
+    public void update (float time)
+    {
+        // adjust the position
+        _velocity.mult(time, _temp);
+        _curpos.addLocal(_temp);
+        _sprite.setLocalTranslation(_curpos);
+
+        // check to see if we're done
+        _accum += time;
+        if (_accum >= _duration) {
+            _sprite.pathCompleted();
+        } else {
+            // adjust our velocity due to acceleration
+            _accel.mult(time, _temp);
+            _velocity.addLocal(_temp);
+        }
+    }
+
+    protected Vector3f _curpos, _velocity, _accel;
+    protected float _duration, _accum;
+    protected Vector3f _temp = new Vector3f(0, 0, 0);
+}