Enough AS cast implementation to render a basic character sprite from component bundles.

git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@970 ed5b42cb-e716-0410-a449-f6a68f950b19

src/as/com/threerings/cast/MultiFrameBitmap.as

@@ -0,0 +1,85 @@
+//
+// Nenya library - tools for developing networked games
+// Copyright (C) 2002-2010 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/nenya/
+//
+// 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.cast {
+
+import flash.display.Bitmap;
+import flash.display.Sprite;
+
+import flash.events.Event;
+
+import com.threerings.util.StringUtil;
+
+public class MultiFrameBitmap extends Sprite
+{
+    public function MultiFrameBitmap (frames :Array, fps :Number)
+    {
+        _frames = frames;
+        _bitmap = new Bitmap();
+        _frameRate = fps / 1000.0;
+        addChild(_bitmap);
+        setFrame(0);
+        addEventListener(Event.ENTER_FRAME, enterFrame);
+    }
+
+    public function enterFrame (event :Event) :void
+    {
+        if (_start == 0) {
+            _start = (new Date().time);
+        }
+
+        var elapsedTime :int = (new Date().time - _start);
+        var frameIndex :int = Math.floor(elapsedTime * _frameRate);
+        var totalFrames :int = _frames.length;
+        if (frameIndex >= totalFrames) {
+            frameIndex = frameIndex % totalFrames;
+        }
+
+        setFrame(frameIndex);
+    }
+
+    protected function setFrame (index :int) :void
+    {
+        if (_curFrameIndex != index) {
+            _bitmap.bitmapData = Bitmap(_frames[index]).bitmapData;
+            _curFrameIndex = index;
+        }
+    }
+
+    public function getFrame (index :int) :Bitmap
+    {
+        return _frames[index];
+    }
+
+    public function getFrameCount () :int
+    {
+        return _frames.length;
+    }
+
+    protected var _frames :Array;
+
+    protected var _bitmap :Bitmap;
+
+    protected var _start :int;
+
+    protected var _frameRate :Number;
+
+    protected var _curFrameIndex :int = -1;
+}
+}