Factored out the flip-buffer versus volatile image back-buffer code into

start-time selectable implementations. Modified back buffer to use
BufferCapabilities.FlipContents.COPIED which should do what we need in
terms of providing us with the current frame's contents on which to paint.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@2468 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/FlipFrameManager.java

@@ -0,0 +1,70 @@
+//
+// $Id: FlipFrameManager.java,v 1.1 2003/04/26 17:56:26 mdb Exp $
+
+package com.threerings.media;
+
+import java.awt.BufferCapabilities;
+import java.awt.Graphics2D;
+import java.awt.ImageCapabilities;
+import java.awt.Rectangle;
+import java.awt.image.BufferStrategy;
+
+import javax.swing.JFrame;
+
+import com.threerings.media.timer.MediaTimer;
+
+/**
+ * A {@link FrameManager} extension that uses a flip-buffer (via {@link
+ * BufferStrategy} to do its rendering.
+ */
+public class FlipFrameManager extends FrameManager
+{
+    // documentation inherited
+    protected void paint (long tickStamp)
+    {
+        // create our buffer strategy if we don't already have one
+        if (_bufstrat == null) {
+            BufferCapabilities cap = new BufferCapabilities(
+                new ImageCapabilities(true), new ImageCapabilities(true),
+                BufferCapabilities.FlipContents.COPIED);
+            _frame.createBufferStrategy(2);
+            _bufstrat = _frame.getBufferStrategy();
+        }
+
+        // start out assuming we can do an incremental render
+        boolean incremental = true;
+
+        do {
+            Graphics2D gfx = (Graphics2D)_bufstrat.getDrawGraphics();
+
+            // dirty everything if we're not incrementally rendering
+            if (!incremental) {
+                Log.info("Doing non-incremental render; contents lost.");
+                _frame.update(gfx);
+            }
+
+            // request to paint our participants and components and bail
+            // if they paint nothing
+            if (!paint(gfx)) {
+                return;
+            }
+
+            // flip our buffer to visible
+            _bufstrat.show();
+
+            // if we loop through a second time, we'll need to rerender
+            // everything
+            incremental = false;
+
+        } while (_bufstrat.contentsLost());
+    }
+
+    // documentation inherited
+    protected void restoreFromBack (Rectangle dirty)
+    {
+        // nothing doing
+    }
+
+    /** The buffer strategy used to do our rendering. */
+    protected BufferStrategy _bufstrat;
+}