--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fontservices/textshaperplugin/IcuSource/layout/LookupTables.cpp	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,85 @@
+/*
+ *
+ * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
+ *
+ */
+
+#include "LETypes.h"
+#include "LayoutTables.h"
+#include "LookupTables.h"
+#include "LESwaps.h"
+
+U_NAMESPACE_BEGIN
+
+/*
+    These are the rolled-up versions of the uniform binary search.
+    Someday, if we need more performance, we can un-roll them.
+    
+    Note: I put these in the base class, so they only have to
+    be written once. Since the base class doesn't define the
+    segment table, these routines assume that it's right after
+    the binary search header.
+
+    Another way to do this is to put each of these routines in one
+    of the derived classes, and implement it in the others by casting
+    the "this" pointer to the type that has the implementation.
+*/ 
+const LookupSegment *BinarySearchLookupTable::lookupSegment(const LookupSegment *segments, LEGlyphID glyph) const
+{
+    le_int16  unity = SWAPW(unitSize);
+    le_int16  probe = SWAPW(searchRange);
+    le_int16  extra = SWAPW(rangeShift);
+    TTGlyphID ttGlyph = (TTGlyphID) LE_GET_GLYPH(glyph);
+    const LookupSegment *entry = segments;
+    const LookupSegment *trial = (const LookupSegment *) ((char *) entry + extra);
+
+    if (SWAPW(trial->lastGlyph) <= ttGlyph) {
+        entry = trial;
+    }
+
+    while (probe > unity) {
+        probe >>= 1;
+        trial = (const LookupSegment *) ((char *) entry + probe);
+
+        if (SWAPW(trial->lastGlyph) <= ttGlyph) {
+            entry = trial;
+        }
+    }
+
+    if (SWAPW(entry->firstGlyph) <= ttGlyph) {
+        return entry;
+    }
+
+    return NULL;
+}
+
+const LookupSingle *BinarySearchLookupTable::lookupSingle(const LookupSingle *entries, LEGlyphID glyph) const
+{
+    le_int16  unity = SWAPW(unitSize);
+    le_int16  probe = SWAPW(searchRange);
+    le_int16  extra = SWAPW(rangeShift);
+    TTGlyphID ttGlyph = (TTGlyphID) LE_GET_GLYPH(glyph);
+    const LookupSingle *entry = entries;
+    const LookupSingle *trial = (const LookupSingle *) ((char *) entry + extra);
+
+    if (SWAPW(trial->glyph) <= ttGlyph) {
+        entry = trial;
+    }
+
+    while (probe > unity) {
+        probe >>= 1;
+        trial = (const LookupSingle *) ((char *) entry + probe);
+
+        if (SWAPW(trial->glyph) <= ttGlyph) {
+            entry = trial;
+        }
+    }
+
+    if (SWAPW(entry->glyph) == ttGlyph) {
+        return entry;
+    }
+
+    return NULL;
+}
+
+U_NAMESPACE_END