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diff --git a/libjava/classpath/gnu/java/awt/font/opentype/truetype/GlyphMeasurer.java b/libjava/classpath/gnu/java/awt/font/opentype/truetype/GlyphMeasurer.java
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+/* GlyphMeasurer.java -- Helper for measuring TrueType glyphs.
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.font.opentype.truetype;
+
+import java.awt.FontFormatException;
+import java.nio.ByteBuffer;
+import java.nio.ShortBuffer;
+
+
+/**
+ * A class for measuring TrueType and OpenType glyphs.
+ *
+ * <p><b>Lack of Thread Safety:</b> Glyph measurers are intentionally
+ * <i>not</i> safe to access from multiple concurrent
+ * threads. Synchronization needs to be performed externally. Usually,
+ * the font has already obtained a lock before calling the scaler,
+ * which in turn calls the GlyphMeasurer. It would thus be wasteful to
+ * acquire additional locks for the GlyphMeasurer.
+ *
+ * @author Sascha Brawer (brawer@dandelis.ch)
+ */
+final class GlyphMeasurer
+{
+  /**
+   * A view buffer that allows accessing the contents of the
+   * font&#x2019;s <code>hmtx</code> table as shorts.
+   */
+  private final ShortBuffer horizontalGlyphMetrics;
+
+
+  /**
+   * A view buffer that allows accessing the contents of the
+   * font&#x2019;s <code>vmtx</code> table as shorts.
+   */
+  private final ShortBuffer verticalGlyphMetrics;
+
+
+  private final int numLongHorizontalMetricsEntries;
+  private final int numLongVerticalMetricsEntries;
+
+  private final int horizontalAscent;
+  private final int verticalAscent;
+
+  private final int horizontalDescent;
+  private final int verticalDescent;
+
+  private final int horizontalLineGap;
+
+
+  /**
+   * Constructs a GlyphMeasurer from TrueType/OpenType font tables.
+   *
+   * @param hhea the <code>hhea</code> table, which contains
+   * information about horizontal metrics that is common to all
+   * glyphs.
+   *
+   * @param hmtx the <code>hmtx</code> table, which contains
+   * glyph-specific information about horizontal metrics.
+   *
+   * @param vhea the <code>vhea</code> table, which contains
+   * information about vertical metrics that is common to all
+   * glyphs. If a font does not provide such a table, pass
+   * <code>null</code>.
+   *
+   * @param vmtx the <code>vmtx</code> table, which contains
+   * glyph-specific information about vertical metrics.  If a font
+   * does not provide such a table, pass <code>null</code>.
+   */
+  GlyphMeasurer(ByteBuffer hhea, ByteBuffer hmtx,
+                ByteBuffer vhea, ByteBuffer vmtx)
+    throws FontFormatException
+  {
+    if ((hhea.getInt(0) != 0x00010000) || (hhea.getInt(30) != 0))
+      throw new FontFormatException("unsupported hhea format");
+
+    horizontalAscent = hhea.getShort(4);
+    horizontalDescent = hhea.getShort(6);
+    horizontalLineGap = hhea.getShort(8);
+
+    numLongHorizontalMetricsEntries = hhea.getChar(34);
+    horizontalGlyphMetrics = hmtx.asShortBuffer();
+
+    if (vhea != null)
+    {
+      verticalAscent = vhea.getShort(4);
+      verticalDescent = vhea.getShort(6);
+      numLongVerticalMetricsEntries = vhea.getChar(34);
+      verticalGlyphMetrics = vmtx.asShortBuffer();
+    }
+    else
+    {
+      verticalAscent = /* advanceWidthMax */ hhea.getChar(10) / 2;
+      verticalDescent = -verticalAscent;
+      numLongVerticalMetricsEntries = 0;
+      verticalGlyphMetrics = null;
+    }
+  }
+
+
+  /**
+   * Returns the distance from the baseline to the highest ascender.
+   *
+   * @param horizontal <code>true</code> for horizontal line layout,
+   * <code>false</code> for vertical line layout.
+   *
+   * @return the maximal ascent, in font units.
+   */
+  public int getAscent(boolean horizontal)
+  {
+    return horizontal ? horizontalAscent : verticalAscent;
+  }
+
+
+  /**
+   * Returns the distance from the baseline to the lowest descender.
+   *
+   * @param horizontal <code>true</code> for horizontal line layout,
+   * <code>false</code> for vertical line layout.
+   *
+   * @return the maximal descent, in font units.
+   */
+  public int getDescent(boolean horizontal)
+  {
+    return horizontal ? horizontalDescent : verticalDescent;
+  }
+
+
+  /**
+   * Returns the typographic line gap.
+   *
+   * @param horizontal <code>true</code> for horizontal line layout,
+   * <code>false</code> for vertical line layout.
+   *
+   * @return the line gap, in font units.
+   */
+  public int getLineGap(boolean horizontal)
+  {
+    return horizontalLineGap;
+  }
+
+
+  /**
+   * Determines the advance width of a glyph, without considering
+   * hinting.
+   *
+   * @param glyphIndex the index of the glyph whose advance width is
+   * to be determined.
+   *
+   * @param horizontal <code>true</code> for horizontal line layout,
+   * <code>false</code> for vertical line layout.
+   *
+   * @return the advance width, in font units.
+   */
+  public int getAdvanceWidth(int glyphIndex, boolean horizontal)
+  {
+    if (!horizontal)
+      return 0;
+
+    glyphIndex = Math.min(glyphIndex,
+                          numLongHorizontalMetricsEntries - 1);
+    return horizontalGlyphMetrics.get(glyphIndex << 1);
+  }
+
+
+  /**
+   * Determines the advance width of a glyph, without considering
+   * hinting.
+   *
+   * @param glyphIndex the index of the glyph whose advance width is
+   * to be determined.
+   *
+   * @param horizontal <code>true</code> for horizontal line layout,
+   * <code>false</code> for vertical line layout.
+   *
+   * @return the advance width, in font units.
+   */
+  public int getAdvanceHeight(int glyphIndex, boolean horizontal)
+  {
+    if (horizontal)
+      return 0;
+
+    /* If a font does not provide vertical glyph metrics, advance
+     * by the height of one horizontal line.
+     */
+    if (verticalGlyphMetrics == null)
+      return horizontalAscent - horizontalDescent + horizontalLineGap;
+
+    glyphIndex = Math.min(glyphIndex,
+                          numLongVerticalMetricsEntries - 1);
+    return verticalGlyphMetrics.get(glyphIndex << 1);
+  }
+}