Behold Vilya, Ring of Air and repository for our game and virtual worldly

extensions to the distributed environment provided by Narya.


git-svn-id: svn+ssh://src.earth.threerings.net/vilya/trunk@1 c613c5cb-e716-0410-b11b-feb51c14d237

src/java/com/threerings/whirled/tools/xml/SceneWriter.java

@@ -0,0 +1,121 @@
+//
+// $Id: SceneWriter.java 4191 2006-06-13 22:42:20Z ray $
+//
+// Narya library - tools for developing networked games
+// Copyright (C) 2002-2004 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.whirled.tools.xml;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.HashMap;
+
+import org.xml.sax.SAXException;
+import org.xml.sax.helpers.AttributesImpl;
+
+import com.megginson.sax.DataWriter;
+import com.threerings.tools.xml.NestableWriter;
+
+import com.threerings.whirled.Log;
+import com.threerings.whirled.data.AuxModel;
+import com.threerings.whirled.data.SceneModel;
+
+/**
+ * Generates an XML representation of an {@link SceneModel}.
+ */
+public class SceneWriter
+{
+    /** The outer element used to enclose our scene definition. */
+    public static final String OUTER_ELEMENT = "scene";
+
+    /**
+     * Registers a writer for writing auxiliary scene models of the
+     * supplied class.
+     */
+    public void registerAuxWriter (Class aclass, NestableWriter writer)
+    {
+        _auxers.put(aclass, writer);
+    }
+
+    /**
+     * Writes the supplied scene out to the specified file.
+     */
+    public void writeScene (File out, SceneModel model)
+        throws IOException, SAXException
+    {
+        FileWriter fout = new FileWriter(out);
+        DataWriter dout = new DataWriter(fout);
+        dout.setIndentStep(2);
+        dout.startDocument();
+        writeSceneModel(model, dout);
+        dout.endDocument();
+        fout.close();
+    }
+
+    /**
+     * Writes the data for the supplied {@link SceneModel} to the XML data
+     * writer supplied. The writer should already be configured with the
+     * appropriate indentation level so that this writer can simply output
+     * its elements and allow the calling code to determine where in the
+     * greater scene description file the scene data should live.
+     */
+    public void writeSceneModel (SceneModel model, DataWriter writer)
+        throws SAXException
+    {
+        AttributesImpl attrs = new AttributesImpl();
+        addSceneAttributes(model, attrs);
+        writer.startElement("", OUTER_ELEMENT, "", attrs);
+        writeSceneData(model, writer);
+        writer.endElement(OUTER_ELEMENT);
+    }
+
+    /**
+     * Adds attributes to the top-level element before it gets written.
+     */
+    protected void addSceneAttributes (
+        SceneModel model, AttributesImpl attrs)
+    {
+        attrs.addAttribute("", "name", "", "", model.name);
+        attrs.addAttribute("", "version", "", "",
+                           Integer.toString(model.version));
+    }
+
+    /**
+     * Writes just the scene data which is handy for derived classes which
+     * may wish to add their own scene data to the scene output.
+     */
+    protected void writeSceneData (SceneModel model, DataWriter writer)
+        throws SAXException
+    {
+        // write out our auxiliary scene models
+        for (int ii = 0; ii < model.auxModels.length; ii++) {
+            AuxModel amodel = model.auxModels[ii];
+            NestableWriter awriter = (NestableWriter)
+                _auxers.get(amodel.getClass());
+            if (awriter != null) {
+                awriter.write(amodel, writer);
+            } else {
+                Log.warning("No writer registered for auxiliary scene model " +
+                            "[mclass=" + amodel.getClass() + "].");
+            }
+        }
+    }
+
+    protected HashMap _auxers = new HashMap();
+}