fontservices/textshaperplugin/IcuSource/layout/CoverageTables.cpp
changeset 0 1fb32624e06b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fontservices/textshaperplugin/IcuSource/layout/CoverageTables.cpp	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,87 @@
+/*
+ *
+ * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
+ *
+ */
+
+#include "LETypes.h"
+#include "OpenTypeTables.h"
+#include "OpenTypeUtilities.h"
+#include "CoverageTables.h"
+#include "LESwaps.h"
+
+U_NAMESPACE_BEGIN
+
+le_int32 CoverageTable::getGlyphCoverage(LEGlyphID glyphID) const
+{
+    switch(SWAPW(coverageFormat))
+    {
+    case 0:
+        return -1;
+
+    case 1:
+    {
+        const CoverageFormat1Table *f1Table = (const CoverageFormat1Table *) this;
+
+        return f1Table->getGlyphCoverage(glyphID);
+    }
+
+    case 2:
+    {
+        const CoverageFormat2Table *f2Table = (const CoverageFormat2Table *) this;
+
+        return f2Table->getGlyphCoverage(glyphID);
+    }
+
+    default:
+        return -1;
+    }
+}
+
+le_int32 CoverageFormat1Table::getGlyphCoverage(LEGlyphID glyphID) const
+{
+    TTGlyphID ttGlyphID = (TTGlyphID) LE_GET_GLYPH(glyphID);
+    le_uint16 count = SWAPW(glyphCount);
+    le_uint8 bit = OpenTypeUtilities::highBit(count);
+    le_uint16 power = 1 << bit;
+    le_uint16 extra = count - power;
+    le_uint16 probe = power;
+    le_uint16 index = 0;
+
+    if (SWAPW(glyphArray[extra]) <= ttGlyphID) {
+        index = extra;
+    }
+
+    while (probe > (1 << 0)) {
+        probe >>= 1;
+
+        if (SWAPW(glyphArray[index + probe]) <= ttGlyphID) {
+            index += probe;
+        }
+    }
+
+    if (SWAPW(glyphArray[index]) == ttGlyphID) {
+        return index;
+    }
+
+    return -1;
+}
+
+le_int32 CoverageFormat2Table::getGlyphCoverage(LEGlyphID glyphID) const
+{
+    TTGlyphID ttGlyphID = (TTGlyphID) LE_GET_GLYPH(glyphID);
+    le_uint16 count = SWAPW(rangeCount);
+    le_int32 rangeIndex =
+        OpenTypeUtilities::getGlyphRangeIndex(ttGlyphID, rangeRecordArray, count);
+
+    if (rangeIndex < 0) {
+        return -1;
+    }
+
+    TTGlyphID firstInRange = SWAPW(rangeRecordArray[rangeIndex].firstGlyph);
+    le_uint16  startCoverageIndex = SWAPW(rangeRecordArray[rangeIndex].rangeValue);
+
+    return startCoverageIndex + (ttGlyphID - firstInRange);
+}
+
+U_NAMESPACE_END