// Copyright 2003 Adam Megacz, see the COPYING file for licensing [GPL]
package org.xwt;
+import java.io.*;
+import org.xwt.js.*;
+import org.xwt.util.*;
+import org.xwt.translators.*;
/**
- * <p>
* The in-memory representation of a PNG or GIF image. It is
- * read-only. It is usually passed to DoubleBuffer.drawPicture()
- * </p>
+ * read-only. It is usually passed to PixelBuffer.drawPicture()
*
- * <p>
* Implementations of the Platform class should return objects
* supporting this interface from the createPicture() method. These
* implementations may choose to implement caching strategies (for
* example, using a Pixmap on X11).
- * </p>
*/
-public abstract class Picture {
- public abstract int getHeight();
- public abstract int getWidth();
+public class Picture {
+
+ public Picture() { this.res = null; }
+ public Picture(Res r) { this.res = r; }
+ private static Cache cache = new Cache(100); ///< Picture, keyed by the Res that loaded them
+
+ public Res res = null; ///< the resource we were loaded from
+ public int width = -1; ///< the width of the image
+ public int height = -1; ///< the height of the image
+ public int[] data = null; ///< argb samples
+ public boolean isLoaded = false; ///< true iff the image is fully loaded
+
+ /** turns a resource into a Picture.Source and passes it to the callback */
+ public static Picture load(final Res r, final Scheduler.Task callback) {
+ Picture ret = (Picture)cache.get(r);
+ if (ret == null) cache.put(r, ret = Platform.createPicture(r));
+ if (!ret.isLoaded && callback != null)
+ new java.lang.Thread() { public void run() {
+ try {
+ PushbackInputStream pbis = new PushbackInputStream(r.getInputStream());
+ Picture p = null;
+ int firstByte = pbis.read();
+ if (firstByte == -1) throw new JSExn("empty stream reading image");
+ pbis.unread(firstByte);
+ if ((firstByte & 0xff) == 'G') GIF.load(pbis, p);
+ else if ((firstByte & 0xff) == 137) PNG.load(pbis, p);
+ else if ((firstByte & 0xff) == 0xff) Platform.decodeJPEG(pbis, p);
+ else throw new JSExn("couldn't figure out image type from first byte");
+ Scheduler.add(callback);
+ } catch (Exception e) {
+ Log.log(this, "exception while loading image");
+ Log.log(this, e);
+ }
+ } }.start();
+ return ret;
+ }
}