--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fontservices/textshaperplugin/IcuSource/layout/KernTable.cpp	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,195 @@
+/*
+ * @(#)KernTable.cpp	1.1 04/10/13
+ *
+ * (C) Copyright IBM Corp. 2004-2005 - All Rights Reserved
+ *
+ */
+
+#include "KernTable.h"
+
+#include "LESwaps.h"
+
+#include <stdio.h>
+
+#define DEBUG 0
+
+U_NAMESPACE_BEGIN
+
+struct PairInfo {
+  le_uint32 key;   // sigh, MSVC compiler gags on union here
+  le_int16  value; // fword, kern value in funits
+};
+#define KERN_PAIRINFO_SIZE 6
+
+struct Subtable_0 {
+  le_uint16 nPairs;
+  le_uint16 searchRange;
+  le_uint16 entrySelector;
+  le_uint16 rangeShift;
+};
+#define KERN_SUBTABLE_0_HEADER_SIZE 8
+
+// Kern table version 0 only
+struct SubtableHeader {
+  le_uint16 version;
+  le_uint16 length;
+  le_uint16 coverage;
+};
+#define KERN_SUBTABLE_HEADER_SIZE 6
+
+// Version 0 only, version 1 has different layout
+struct KernTableHeader {
+  le_uint16 version;
+  le_uint16 nTables;
+};
+#define KERN_TABLE_HEADER_SIZE 4
+
+#define COVERAGE_HORIZONTAL 0x1
+#define COVERAGE_MINIMUM 0x2
+#define COVERAGE_CROSS 0x4
+#define COVERAGE_OVERRIDE 0x8
+
+KernTable::KernTable(const LEFontInstance* font, const void* tableData) 
+  : pairs(0), font(font)
+{
+  const KernTableHeader* header = (const KernTableHeader*)tableData;
+  if (header == 0) {
+#if DEBUG
+    fprintf(stderr, "no kern data\n");
+    fflush(stderr);
+#endif
+    return;
+  }
+
+#if DEBUG
+  // dump first 32 bytes of header
+  for (int i = 0; i < 64; ++i) {
+    fprintf(stderr, "%0.2x ", ((const char*)tableData)[i]&0xff);
+    if (((i+1)&0xf) == 0) {
+      fprintf(stderr, "\n");
+    } else if (((i+1)&0x7) == 0) {
+      fprintf(stderr, "  ");
+    }
+  }
+  fflush(stderr);
+#endif
+
+  if (header->version == 0 && SWAPW(header->nTables) > 0) {
+    const SubtableHeader* subhead = (const SubtableHeader*)((char*)tableData + KERN_TABLE_HEADER_SIZE);
+    if (subhead->version == 0) {
+      coverage = SWAPW(subhead->coverage);
+      if (coverage & COVERAGE_HORIZONTAL) { // only handle horizontal kerning
+	const Subtable_0* table = (const Subtable_0*)((char*)subhead + KERN_SUBTABLE_HEADER_SIZE);
+	nPairs = SWAPW(table->nPairs);
+	searchRange = SWAPW(table->searchRange);
+	entrySelector = SWAPW(table->entrySelector);
+	rangeShift = SWAPW(table->rangeShift);
+	pairs = (const PairInfo*)((char*)table + KERN_SUBTABLE_0_HEADER_SIZE);
+
+#if DEBUG
+	fprintf(stderr, "coverage: %0.4x nPairs: %d pairs 0x%x\n", coverage, nPairs, pairs);
+	fprintf(stderr, "  searchRange: %d entrySelector: %d rangeShift: %d\n", searchRange, entrySelector, rangeShift);
+	fflush(stderr);
+
+	{
+	  // dump part of the pair list
+	  char ids[256];
+	  for (int i = 256; --i >= 0;) {
+	    LEGlyphID id = font->mapCharToGlyph(i);
+	    if (id < 256) {
+	      ids[id] = (char)i;
+	    }
+	  }
+
+	  const PairInfo* p = pairs;
+	  for (i = 0; i < nPairs; ++i, p = (const PairInfo*)((char*)p+KERN_PAIRINFO_SIZE)) {
+  	    le_uint32 k = SWAPL(p->key);
+	    le_uint16 left = (k >> 16) & 0xffff;
+	    le_uint16 right = k & 0xffff;
+	    if (left < 256 && right < 256) {
+	      char c = ids[left];
+	      if (c > 0x20 && c < 0x7f) {
+		fprintf(stderr, "%c/", c & 0xff);
+	      } else {
+		fprintf(stderr, "%0.2x/", c & 0xff);
+	      }
+	      c = ids[right];
+	      if (c > 0x20 && c < 0x7f) {
+		fprintf(stderr, "%c ", c & 0xff);
+	      } else {
+		fprintf(stderr, "%0.2x ", c & 0xff);
+	      }
+	    }
+	  }
+	  fflush(stderr);
+	}
+#endif
+      }
+    }
+  }
+}
+  
+
+/*
+ * Process the glyph positions.  The positions array has two floats for each
+ * glyph, plus a trailing pair to mark the end of the last glyph.
+ */
+//void KernTable::process(const LEGlyphID glyphs[], float* positions, le_int32 glyphCount) 
+void KernTable::process(LEGlyphStorage& storage) 
+{
+  if (pairs) {
+    LEErrorCode success = LE_NO_ERROR;
+
+    le_uint32 key = storage[0]; // no need to mask off high bits
+    float adjust = 0;
+    for (int i = 1, e = storage.getGlyphCount(); i < e; ++i) {
+      key = key << 16 | (storage[i] & 0xffff);
+
+      // argh, to do a binary search, we need to have the pair list in sorted order
+      // but it is not in sorted order on win32 platforms because of the endianness difference
+      // so either I have to swap the element each time I examine it, or I have to swap
+      // all the elements ahead of time and store them in the font
+
+      const PairInfo* p = pairs;
+      const PairInfo* tp = (const PairInfo*)((char*)p + rangeShift);
+      if (key > SWAPL(tp->key)) {
+	p = tp;
+      }
+
+#if DEBUG
+      fprintf(stderr, "binary search for %0.8x\n", key);
+      fflush(stderr);
+#endif
+
+      le_uint32 probe = searchRange;
+      while (probe > KERN_PAIRINFO_SIZE) {
+        probe >>= 1;
+        tp = (const PairInfo*)((char*)p + probe);
+	le_uint32 tkey = SWAPL(tp->key);
+#if DEBUG
+	fprintf(stdout, "   %.3d (%0.8x)\n", ((char*)tp - (char*)pairs)/KERN_PAIRINFO_SIZE, tkey);
+	fflush(stdout);
+#endif
+        if (tkey <= key) {
+	  if (tkey == key) {
+	    le_int16 value = SWAPW(tp->value);
+#if DEBUG
+	    fprintf(stdout, "binary found kerning pair %x:%x at %d, value: 0x%x (%g)\n", 
+		    storage[i-1], storage[i], i, value & 0xffff, font->xUnitsToPoints(value));
+	    fflush(stdout);
+#endif
+	    adjust += font->xUnitsToPoints(value);
+	    break;
+	  }
+	  p = tp;
+        }
+      }
+
+      storage.adjustPosition(i, adjust, 0, success);
+    }
+    storage.adjustPosition(storage.getGlyphCount(), adjust, 0, success);
+  }
+}
+
+U_NAMESPACE_END
+