Robustness improvements to TextRenderer and underlying RectanglePacker.

Added ability to specify a maximum size to which the RectanglePacker
can expand. Added preExpand method to BackingStoreManager to support
early eviction of unused entries instead of always expanding the
backing store, and additionFailed method used when the backing store
can not expand further. Added more robust free list coalescing to
Level. Added support for shrinking of backing store and for eager
compaction when there is a lot of vertical dead space. Added TextFlow
demo which shows how to do dynamic layout of text and which acts as a
stress test for the TextRenderer.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@1083 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 39 insertions, 0 deletions

diff --git a/src/classes/com/sun/opengl/impl/packrect/LevelSet.java b/src/classes/com/sun/opengl/impl/packrect/LevelSet.java
index 561a3fe14..97a1f2e74 100755
--- a/src/classes/com/sun/opengl/impl/packrect/LevelSet.java
+++ b/src/classes/com/sun/opengl/impl/packrect/LevelSet.java
@@ -149,6 +149,39 @@ public class LevelSet {
     nextAddY += (newHeight - oldHeight);
   }
 
+  /** Gets the used height of the levels in this LevelSet. */
+  public int getUsedHeight() {
+    return nextAddY;
+  }
+
+  /** Sets the height of this LevelSet. It is only legal to reduce the
+      height to greater than or equal to the currently used height. */
+  public void setHeight(int height) throws IllegalArgumentException {
+    if (height < getUsedHeight()) {
+      throw new IllegalArgumentException("May not reduce height below currently used height");
+    }
+    h = height;
+  }
+
+  /** Returns the vertical fragmentation ratio of this LevelSet. This
+      is defined as the ratio of the sum of the heights of all
+      completely empty Levels divided by the overall used height of
+      the LevelSet. A high vertical fragmentation ratio indicates that
+      it may be profitable to perform a compaction. */
+  public float verticalFragmentationRatio() {
+    int freeHeight = 0;
+    int usedHeight = getUsedHeight();
+    if (usedHeight == 0)
+      return 0.0f;
+    for (Iterator iter = iterator(); iter.hasNext(); ) {
+      Level level = (Level) iter.next();
+      if (level.isEmpty()) {
+        freeHeight += level.h();
+      }
+    }
+    return (float) freeHeight / (float) usedHeight;
+  }
+
   public Iterator iterator() {
     return levels.iterator();
   }
@@ -171,4 +204,10 @@ public class LevelSet {
       level.updateRectangleReferences();
     }
   }
+
+  /** Clears out all Levels stored in this LevelSet. */
+  public void clear() {
+    levels.clear();
+    nextAddY = 0;
+  }
 }