MakeTiles: implement support for files specifying an animation

src/micropolisj/build_tool/Animation.java

@@ -0,0 +1,84 @@
+package micropolisj.build_tool;
+
+import java.awt.Graphics2D;
+import java.io.*;
+import java.util.*;
+import javax.xml.stream.*;
+import static micropolisj.XML_Helper.*;
+
+class Animation extends MakeTiles.TileImage
+{
+	static final int DEFAULT_DURATION = 125;
+	List<AnimationFrame> frames = new ArrayList<AnimationFrame>();
+
+	public static Animation load(File aniFile)
+		throws IOException
+	{
+		FileInputStream fis = new FileInputStream(aniFile);
+		Animation self = new Animation();
+		self.load(fis);
+		return self;
+	}
+
+	void load(InputStream inStream)
+		throws IOException
+	{
+		try {
+
+		XMLStreamReader in = XMLInputFactory.newInstance().createXMLStreamReader(inStream, "UTF-8");
+		in.nextTag();
+		if (!(in.getEventType() == XMLStreamConstants.START_ELEMENT &&
+			in.getLocalName().equals("micropolis-animation"))) {
+			throw new IOException("Unrecognized file format");
+		}
+
+		while (in.nextTag() != XMLStreamConstants.END_ELEMENT) {
+			assert in.isStartElement();
+
+			String tagName = in.getLocalName();
+			if (tagName.equals("frame")) {
+
+				String tmp = in.getAttributeValue(null, "duration");
+				int duration = tmp != null ? Integer.parseInt(tmp) : DEFAULT_DURATION;
+
+				tmp = in.getElementText();
+				frames.add(
+					new AnimationFrame(
+						MakeTiles.parseFrameSpec(tmp),
+						duration
+					));
+			}
+			else {
+				// unrecognized element
+				skipToEndElement(in);
+			}
+		}
+
+		in.close();
+		inStream.close();
+
+		}
+		catch (XMLStreamException e) {
+			throw new IOException(e);
+		}
+	}
+
+	static class AnimationFrame
+	{
+		MakeTiles.TileImage frame;
+		int duration;
+
+		public AnimationFrame(MakeTiles.TileImage frame, int duration)
+		{
+			this.frame = frame;
+			this.duration = duration;
+		}
+	}
+
+	@Override
+	void drawTo(Graphics2D gr, int destX, int destY, int srcX, int srcY)
+	{
+		if (frames.isEmpty()) { return; }
+		frames.get(0).frame.drawTo(gr, destX, destY, srcX, srcY);
+	}
+}

src/micropolisj/build_tool/MakeTiles.java

@@ -315,6 +315,18 @@ public class MakeTiles
 		return pngFile;
 	}
 
+	static TileImage loadAnimation(String fileName)
+		throws IOException
+	{
+		File f = new File(fileName + ".ani");
+		if (f.exists()) {
+			return Animation.load(f);
+		}
+		else {
+			return loadImage(fileName);
+		}
+	}
+
 	static SourceImage loadImage(String fileName)
 		throws IOException
 	{