Add m-esr52 at 52.6.0

1 files changed, 934 insertions, 0 deletions

diff --git a/gfx/harfbuzz/src/hb-directwrite.cc b/gfx/harfbuzz/src/hb-directwrite.cc
new file mode 100644
index 000000000..b5c1113b1
--- /dev/null
+++ b/gfx/harfbuzz/src/hb-directwrite.cc
@@ -0,0 +1,934 @@
+/*
+ * Copyright © 2015-2016  Ebrahim Byagowi
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ */
+
+#define HB_SHAPER directwrite
+#include "hb-shaper-impl-private.hh"
+
+#include <DWrite_1.h>
+
+#include "hb-directwrite.h"
+
+
+#ifndef HB_DEBUG_DIRECTWRITE
+#define HB_DEBUG_DIRECTWRITE (HB_DEBUG+0)
+#endif
+
+HB_SHAPER_DATA_ENSURE_DECLARE(directwrite, face)
+HB_SHAPER_DATA_ENSURE_DECLARE(directwrite, font)
+
+
+/*
+ * DirectWrite font stream helpers
+ */
+
+// This is a font loader which provides only one font (unlike its original design).
+// For a better implementation which was also source of this
+// and DWriteFontFileStream, have a look at to NativeFontResourceDWrite.cpp in Mozilla
+class DWriteFontFileLoader : public IDWriteFontFileLoader
+{
+private:
+  IDWriteFontFileStream *mFontFileStream;
+public:
+  DWriteFontFileLoader (IDWriteFontFileStream *fontFileStream) {
+    mFontFileStream = fontFileStream;
+  }
+
+  // IUnknown interface
+  IFACEMETHOD(QueryInterface)(IID const& iid, OUT void** ppObject) { return S_OK; }
+  IFACEMETHOD_(ULONG, AddRef)() { return 1; }
+  IFACEMETHOD_(ULONG, Release)() { return 1; }
+
+  // IDWriteFontFileLoader methods
+  virtual HRESULT STDMETHODCALLTYPE CreateStreamFromKey(void const* fontFileReferenceKey,
+    UINT32 fontFileReferenceKeySize,
+    OUT IDWriteFontFileStream** fontFileStream)
+  {
+    *fontFileStream = mFontFileStream;
+    return S_OK;
+  }
+};
+
+class DWriteFontFileStream : public IDWriteFontFileStream
+{
+private:
+  uint8_t *mData;
+  uint32_t mSize;
+public:
+  DWriteFontFileStream(uint8_t *aData, uint32_t aSize)
+  {
+    mData = aData;
+    mSize = aSize;
+  }
+
+  // IUnknown interface
+  IFACEMETHOD(QueryInterface)(IID const& iid, OUT void** ppObject) { return S_OK; }
+  IFACEMETHOD_(ULONG, AddRef)() { return 1; }
+  IFACEMETHOD_(ULONG, Release)() { return 1; }
+
+  // IDWriteFontFileStream methods
+  virtual HRESULT STDMETHODCALLTYPE ReadFileFragment(void const** fragmentStart,
+    UINT64 fileOffset,
+    UINT64 fragmentSize,
+    OUT void** fragmentContext)
+  {
+    // We are required to do bounds checking.
+    if (fileOffset + fragmentSize > mSize) {
+      return E_FAIL;
+    }
+
+    // truncate the 64 bit fileOffset to size_t sized index into mData
+    size_t index = static_cast<size_t> (fileOffset);
+
+    // We should be alive for the duration of this.
+    *fragmentStart = &mData[index];
+    *fragmentContext = nullptr;
+    return S_OK;
+  }
+
+  virtual void STDMETHODCALLTYPE ReleaseFileFragment(void* fragmentContext) { }
+
+  virtual HRESULT STDMETHODCALLTYPE GetFileSize(OUT UINT64* fileSize)
+  {
+    *fileSize = mSize;
+    return S_OK;
+  }
+
+  virtual HRESULT STDMETHODCALLTYPE GetLastWriteTime(OUT UINT64* lastWriteTime)
+  {
+    return E_NOTIMPL;
+  }
+};
+
+
+/*
+* shaper face data
+*/
+
+struct hb_directwrite_shaper_face_data_t {
+  IDWriteFactory *dwriteFactory;
+  IDWriteFontFile *fontFile;
+  IDWriteFontFileStream *fontFileStream;
+  IDWriteFontFileLoader *fontFileLoader;
+  IDWriteFontFace *fontFace;
+  hb_blob_t *faceBlob;
+};
+
+hb_directwrite_shaper_face_data_t *
+_hb_directwrite_shaper_face_data_create(hb_face_t *face)
+{
+  hb_directwrite_shaper_face_data_t *data =
+    (hb_directwrite_shaper_face_data_t *) malloc (sizeof (hb_directwrite_shaper_face_data_t));
+  if (unlikely (!data))
+    return NULL;
+
+  // TODO: factory and fontFileLoader should be cached separately
+  IDWriteFactory* dwriteFactory;
+  DWriteCreateFactory (
+    DWRITE_FACTORY_TYPE_SHARED,
+    __uuidof (IDWriteFactory),
+    (IUnknown**) &dwriteFactory
+  );
+
+  HRESULT hr;
+  hb_blob_t *blob = hb_face_reference_blob (face);
+  IDWriteFontFileStream *fontFileStream = new DWriteFontFileStream (
+    (uint8_t*) hb_blob_get_data (blob, NULL), hb_blob_get_length (blob));
+
+  IDWriteFontFileLoader *fontFileLoader = new DWriteFontFileLoader (fontFileStream);
+  dwriteFactory->RegisterFontFileLoader (fontFileLoader);
+
+  IDWriteFontFile *fontFile;
+  uint64_t fontFileKey = 0;
+  hr = dwriteFactory->CreateCustomFontFileReference (&fontFileKey, sizeof (fontFileKey),
+      fontFileLoader, &fontFile);
+
+#define FAIL(...) \
+  HB_STMT_START { \
+    DEBUG_MSG (DIRECTWRITE, NULL, __VA_ARGS__); \
+    return false; \
+  } HB_STMT_END;
+
+  if (FAILED (hr)) {
+    FAIL ("Failed to load font file from data!");
+    return false;
+  }
+
+  BOOL isSupported;
+  DWRITE_FONT_FILE_TYPE fileType;
+  DWRITE_FONT_FACE_TYPE faceType;
+  UINT32 numberOfFaces;
+  hr = fontFile->Analyze (&isSupported, &fileType, &faceType, &numberOfFaces);
+  if (FAILED (hr) || !isSupported) {
+    FAIL ("Font file is not supported.");
+    return false;
+  }
+
+#undef FAIL
+
+  IDWriteFontFace *fontFace;
+  dwriteFactory->CreateFontFace (faceType, 1, &fontFile, 0,
+    DWRITE_FONT_SIMULATIONS_NONE, &fontFace);
+
+  data->dwriteFactory = dwriteFactory;
+  data->fontFile = fontFile;
+  data->fontFileStream = fontFileStream;
+  data->fontFileLoader = fontFileLoader;
+  data->fontFace = fontFace;
+  data->faceBlob = blob;
+
+  return data;
+}
+
+void
+_hb_directwrite_shaper_face_data_destroy(hb_directwrite_shaper_face_data_t *data)
+{
+  if (data->fontFace)
+    data->fontFace->Release ();
+  if (data->fontFile)
+    data->fontFile->Release ();
+  if (data->dwriteFactory) {
+    if (data->fontFileLoader)
+      data->dwriteFactory->UnregisterFontFileLoader (data->fontFileLoader);
+    data->dwriteFactory->Release ();
+  }
+  if (data->fontFileLoader)
+    delete data->fontFileLoader;
+  if (data->fontFileStream)
+    delete data->fontFileStream;
+  if (data->faceBlob)
+    hb_blob_destroy (data->faceBlob);
+  if (data)
+    free (data);
+}
+
+
+/*
+ * shaper font data
+ */
+
+struct hb_directwrite_shaper_font_data_t {
+};
+
+hb_directwrite_shaper_font_data_t *
+_hb_directwrite_shaper_font_data_create (hb_font_t *font)
+{
+  if (unlikely (!hb_directwrite_shaper_face_data_ensure (font->face))) return NULL;
+
+  hb_directwrite_shaper_font_data_t *data =
+    (hb_directwrite_shaper_font_data_t *) malloc (sizeof (hb_directwrite_shaper_font_data_t));
+  if (unlikely (!data))
+    return NULL;
+
+  return data;
+}
+
+void
+_hb_directwrite_shaper_font_data_destroy (hb_directwrite_shaper_font_data_t *data)
+{
+  free (data);
+}
+
+
+/*
+ * shaper shape_plan data
+ */
+
+struct hb_directwrite_shaper_shape_plan_data_t {};
+
+hb_directwrite_shaper_shape_plan_data_t *
+_hb_directwrite_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
+					       const hb_feature_t *user_features HB_UNUSED,
+					       unsigned int        num_user_features HB_UNUSED,
+					       const int          *coords HB_UNUSED,
+					       unsigned int        num_coords HB_UNUSED)
+{
+  return (hb_directwrite_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
+}
+
+void
+_hb_directwrite_shaper_shape_plan_data_destroy (hb_directwrite_shaper_shape_plan_data_t *data HB_UNUSED)
+{
+}
+
+// Most of TextAnalysis is originally written by Bas Schouten for Mozilla project
+// but now is relicensed to MIT for HarfBuzz use
+class TextAnalysis
+  : public IDWriteTextAnalysisSource, public IDWriteTextAnalysisSink
+{
+public:
+
+  IFACEMETHOD(QueryInterface)(IID const& iid, OUT void** ppObject) { return S_OK; }
+  IFACEMETHOD_(ULONG, AddRef)() { return 1; }
+  IFACEMETHOD_(ULONG, Release)() { return 1; }
+
+  // A single contiguous run of characters containing the same analysis 
+  // results.
+  struct Run
+  {
+    uint32_t mTextStart;   // starting text position of this run
+    uint32_t mTextLength;  // number of contiguous code units covered
+    uint32_t mGlyphStart;  // starting glyph in the glyphs array
+    uint32_t mGlyphCount;  // number of glyphs associated with this run of 
+    // text
+    DWRITE_SCRIPT_ANALYSIS mScript;
+    uint8_t mBidiLevel;
+    bool mIsSideways;
+
+    inline bool ContainsTextPosition(uint32_t aTextPosition) const
+    {
+      return aTextPosition >= mTextStart
+        && aTextPosition <  mTextStart + mTextLength;
+    }
+
+    Run *nextRun;
+  };
+
+public:
+  TextAnalysis(const wchar_t* text,
+    uint32_t textLength,
+    const wchar_t* localeName,
+    DWRITE_READING_DIRECTION readingDirection)
+    : mText(text)
+    , mTextLength(textLength)
+    , mLocaleName(localeName)
+    , mReadingDirection(readingDirection)
+    , mCurrentRun(NULL) { };
+
+  ~TextAnalysis() {
+    // delete runs, except mRunHead which is part of the TextAnalysis object
+    for (Run *run = mRunHead.nextRun; run;) {
+      Run *origRun = run;
+      run = run->nextRun;
+      free (origRun);
+    }
+  }
+
+  STDMETHODIMP GenerateResults(IDWriteTextAnalyzer* textAnalyzer,
+    Run **runHead) {
+    // Analyzes the text using the script analyzer and returns
+    // the result as a series of runs.
+
+    HRESULT hr = S_OK;
+
+    // Initially start out with one result that covers the entire range.
+    // This result will be subdivided by the analysis processes.
+    mRunHead.mTextStart = 0;
+    mRunHead.mTextLength = mTextLength;
+    mRunHead.mBidiLevel =
+      (mReadingDirection == DWRITE_READING_DIRECTION_RIGHT_TO_LEFT);
+    mRunHead.nextRun = NULL;
+    mCurrentRun = &mRunHead;
+
+    // Call each of the analyzers in sequence, recording their results.
+    if (SUCCEEDED (hr = textAnalyzer->AnalyzeScript (this, 0, mTextLength, this))) {
+      *runHead = &mRunHead;
+    }
+
+    return hr;
+  }
+
+  // IDWriteTextAnalysisSource implementation
+
+  IFACEMETHODIMP GetTextAtPosition(uint32_t textPosition,
+    OUT wchar_t const** textString,
+    OUT uint32_t* textLength)
+  {
+    if (textPosition >= mTextLength) {
+      // No text at this position, valid query though.
+      *textString = NULL;
+      *textLength = 0;
+    }
+    else {
+      *textString = mText + textPosition;
+      *textLength = mTextLength - textPosition;
+    }
+    return S_OK;
+  }
+
+  IFACEMETHODIMP GetTextBeforePosition(uint32_t textPosition,
+    OUT wchar_t const** textString,
+    OUT uint32_t* textLength)
+  {
+    if (textPosition == 0 || textPosition > mTextLength) {
+      // Either there is no text before here (== 0), or this
+      // is an invalid position. The query is considered valid thouh.
+      *textString = NULL;
+      *textLength = 0;
+    }
+    else {
+      *textString = mText;
+      *textLength = textPosition;
+    }
+    return S_OK;
+  }
+
+  IFACEMETHODIMP_(DWRITE_READING_DIRECTION)
+    GetParagraphReadingDirection() { return mReadingDirection; }
+
+  IFACEMETHODIMP GetLocaleName(uint32_t textPosition,
+    uint32_t* textLength,
+    wchar_t const** localeName)
+  {
+    return S_OK;
+  }
+
+  IFACEMETHODIMP
+    GetNumberSubstitution(uint32_t textPosition,
+    OUT uint32_t* textLength,
+    OUT IDWriteNumberSubstitution** numberSubstitution)
+  {
+    // We do not support number substitution.
+    *numberSubstitution = NULL;
+    *textLength = mTextLength - textPosition;
+
+    return S_OK;
+  }
+
+  // IDWriteTextAnalysisSink implementation
+
+  IFACEMETHODIMP
+    SetScriptAnalysis(uint32_t textPosition,
+    uint32_t textLength,
+    DWRITE_SCRIPT_ANALYSIS const* scriptAnalysis)
+  {
+    SetCurrentRun(textPosition);
+    SplitCurrentRun(textPosition);
+    while (textLength > 0)
+    {
+      Run *run = FetchNextRun(&textLength);
+      run->mScript = *scriptAnalysis;
+    }
+
+    return S_OK;
+  }
+
+  IFACEMETHODIMP
+    SetLineBreakpoints(uint32_t textPosition,
+    uint32_t textLength,
+    const DWRITE_LINE_BREAKPOINT* lineBreakpoints) { return S_OK; }
+
+  IFACEMETHODIMP SetBidiLevel(uint32_t textPosition,
+    uint32_t textLength,
+    uint8_t explicitLevel,
+    uint8_t resolvedLevel) { return S_OK; }
+
+  IFACEMETHODIMP
+    SetNumberSubstitution(uint32_t textPosition,
+    uint32_t textLength,
+    IDWriteNumberSubstitution* numberSubstitution) { return S_OK; }
+
+protected:
+  Run *FetchNextRun(IN OUT uint32_t* textLength)
+  {
+    // Used by the sink setters, this returns a reference to the next run.
+    // Position and length are adjusted to now point after the current run
+    // being returned.
+
+    Run *origRun = mCurrentRun;
+    // Split the tail if needed (the length remaining is less than the
+    // current run's size).
+    if (*textLength < mCurrentRun->mTextLength)
+    {
+      SplitCurrentRun (mCurrentRun->mTextStart + *textLength);
+    }
+    else
+    {
+      // Just advance the current run.
+      mCurrentRun = mCurrentRun->nextRun;
+    }
+    *textLength -= origRun->mTextLength;
+
+    // Return a reference to the run that was just current.
+    return origRun;
+  }
+
+  void SetCurrentRun(uint32_t textPosition)
+  {
+    // Move the current run to the given position.
+    // Since the analyzers generally return results in a forward manner,
+    // this will usually just return early. If not, find the
+    // corresponding run for the text position.
+
+    if (mCurrentRun && mCurrentRun->ContainsTextPosition (textPosition))
+    {
+      return;
+    }
+
+    for (Run *run = &mRunHead; run; run = run->nextRun) {
+      if (run->ContainsTextPosition (textPosition))
+      {
+        mCurrentRun = run;
+        return;
+      }
+    }
+    //NS_NOTREACHED("We should always be able to find the text position in one \
+            //                of our runs");
+  }
+
+  void SplitCurrentRun(uint32_t splitPosition)
+  {
+    if (!mCurrentRun)
+    {
+      //NS_ASSERTION(false, "SplitCurrentRun called without current run.");
+      // Shouldn't be calling this when no current run is set!
+      return;
+    }
+    // Split the current run.
+    if (splitPosition <= mCurrentRun->mTextStart)
+    {
+      // No need to split, already the start of a run
+      // or before it. Usually the first.
+      return;
+    }
+    Run *newRun = (Run*) malloc (sizeof (Run));
+
+    *newRun = *mCurrentRun;
+
+    // Insert the new run in our linked list.
+    newRun->nextRun = mCurrentRun->nextRun;
+    mCurrentRun->nextRun = newRun;
+
+    // Adjust runs' text positions and lengths.
+    uint32_t splitPoint = splitPosition - mCurrentRun->mTextStart;
+    newRun->mTextStart += splitPoint;
+    newRun->mTextLength -= splitPoint;
+    mCurrentRun->mTextLength = splitPoint;
+    mCurrentRun = newRun;
+  }
+
+protected:
+  // Input
+  // (weak references are fine here, since this class is a transient
+  //  stack-based helper that doesn't need to copy data)
+  uint32_t mTextLength;
+  const wchar_t* mText;
+  const wchar_t* mLocaleName;
+  DWRITE_READING_DIRECTION mReadingDirection;
+
+  // Current processing state.
+  Run *mCurrentRun;
+
+  // Output is a list of runs starting here
+  Run  mRunHead;
+};
+
+static inline uint16_t hb_uint16_swap (const uint16_t v)
+{ return (v >> 8) | (v << 8); }
+static inline uint32_t hb_uint32_swap (const uint32_t v)
+{ return (hb_uint16_swap(v) << 16) | hb_uint16_swap(v >> 16); }
+
+/*
+ * shaper
+ */
+
+static hb_bool_t
+_hb_directwrite_shape_full(hb_shape_plan_t    *shape_plan,
+  hb_font_t          *font,
+  hb_buffer_t        *buffer,
+  const hb_feature_t *features,
+  unsigned int        num_features,
+  float               lineWidth)
+{
+  hb_face_t *face = font->face;
+  hb_directwrite_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
+  hb_directwrite_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
+  IDWriteFactory *dwriteFactory = face_data->dwriteFactory;
+  IDWriteFontFace *fontFace = face_data->fontFace;
+
+  IDWriteTextAnalyzer* analyzer;
+  dwriteFactory->CreateTextAnalyzer(&analyzer);
+
+  unsigned int scratch_size;
+  hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
+#define ALLOCATE_ARRAY(Type, name, len) \
+  Type *name = (Type *) scratch; \
+  { \
+    unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
+    assert (_consumed <= scratch_size); \
+    scratch += _consumed; \
+    scratch_size -= _consumed; \
+  }
+
+#define utf16_index() var1.u32
+
+  ALLOCATE_ARRAY(wchar_t, textString, buffer->len * 2);
+
+  unsigned int chars_len = 0;
+  for (unsigned int i = 0; i < buffer->len; i++)
+  {
+    hb_codepoint_t c = buffer->info[i].codepoint;
+    buffer->info[i].utf16_index() = chars_len;
+    if (likely(c <= 0xFFFFu))
+      textString[chars_len++] = c;
+    else if (unlikely(c > 0x10FFFFu))
+      textString[chars_len++] = 0xFFFDu;
+    else {
+      textString[chars_len++] = 0xD800u + ((c - 0x10000u) >> 10);
+      textString[chars_len++] = 0xDC00u + ((c - 0x10000u) & ((1u << 10) - 1));
+    }
+  }
+
+  ALLOCATE_ARRAY(WORD, log_clusters, chars_len);
+  // if (num_features)
+  {
+    /* Need log_clusters to assign features. */
+    chars_len = 0;
+    for (unsigned int i = 0; i < buffer->len; i++)
+    {
+      hb_codepoint_t c = buffer->info[i].codepoint;
+      unsigned int cluster = buffer->info[i].cluster;
+      log_clusters[chars_len++] = cluster;
+      if (hb_in_range(c, 0x10000u, 0x10FFFFu))
+        log_clusters[chars_len++] = cluster; /* Surrogates. */
+    }
+  }
+
+  // TODO: Handle TEST_DISABLE_OPTIONAL_LIGATURES
+
+  DWRITE_READING_DIRECTION readingDirection = buffer->props.direction ? 
+    DWRITE_READING_DIRECTION_RIGHT_TO_LEFT :
+    DWRITE_READING_DIRECTION_LEFT_TO_RIGHT;
+
+  /*
+  * There's an internal 16-bit limit on some things inside the analyzer,
+  * but we never attempt to shape a word longer than 64K characters
+  * in a single gfxShapedWord, so we cannot exceed that limit.
+  */
+  uint32_t textLength = buffer->len;
+
+  TextAnalysis analysis(textString, textLength, NULL, readingDirection);
+  TextAnalysis::Run *runHead;
+  HRESULT hr;
+  hr = analysis.GenerateResults(analyzer, &runHead);
+
+#define FAIL(...) \
+  HB_STMT_START { \
+    DEBUG_MSG (DIRECTWRITE, NULL, __VA_ARGS__); \
+    return false; \
+  } HB_STMT_END;
+
+  if (FAILED (hr))
+  {
+    FAIL ("Analyzer failed to generate results.");
+    return false;
+  }
+
+  uint32_t maxGlyphCount = 3 * textLength / 2 + 16;
+  uint32_t glyphCount;
+  bool isRightToLeft = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
+
+  const wchar_t localeName[20] = {0};
+  if (buffer->props.language != NULL)
+  {
+    mbstowcs ((wchar_t*) localeName,
+      hb_language_to_string (buffer->props.language), 20);
+  }
+
+  DWRITE_TYPOGRAPHIC_FEATURES singleFeatures;
+  singleFeatures.featureCount = num_features;
+  if (num_features)
+  {
+    DWRITE_FONT_FEATURE* dwfeatureArray = (DWRITE_FONT_FEATURE*)
+      malloc (sizeof (DWRITE_FONT_FEATURE) * num_features);
+    for (unsigned int i = 0; i < num_features; ++i)
+    {
+      dwfeatureArray[i].nameTag = (DWRITE_FONT_FEATURE_TAG)
+        hb_uint32_swap (features[i].tag);
+      dwfeatureArray[i].parameter = features[i].value;
+    }
+    singleFeatures.features = dwfeatureArray;
+  }
+  const DWRITE_TYPOGRAPHIC_FEATURES* dwFeatures =
+    (const DWRITE_TYPOGRAPHIC_FEATURES*) &singleFeatures;
+  const uint32_t featureRangeLengths[] = { textLength };
+
+  uint16_t* clusterMap = (uint16_t*) malloc (textLength * sizeof (uint16_t));
+  DWRITE_SHAPING_TEXT_PROPERTIES* textProperties = (DWRITE_SHAPING_TEXT_PROPERTIES*)
+    malloc (textLength * sizeof (DWRITE_SHAPING_TEXT_PROPERTIES));
+retry_getglyphs:
+  uint16_t* glyphIndices = (uint16_t*) malloc (maxGlyphCount * sizeof (uint16_t));
+  DWRITE_SHAPING_GLYPH_PROPERTIES* glyphProperties = (DWRITE_SHAPING_GLYPH_PROPERTIES*)
+    malloc (maxGlyphCount * sizeof (DWRITE_SHAPING_GLYPH_PROPERTIES));
+
+  hr = analyzer->GetGlyphs (textString, textLength, fontFace, FALSE,
+    isRightToLeft, &runHead->mScript, localeName, NULL, &dwFeatures,
+    featureRangeLengths, 1, maxGlyphCount, clusterMap, textProperties, glyphIndices,
+    glyphProperties, &glyphCount);
+
+  if (unlikely (hr == HRESULT_FROM_WIN32 (ERROR_INSUFFICIENT_BUFFER)))
+  {
+    free (glyphIndices);
+    free (glyphProperties);
+
+    maxGlyphCount *= 2;
+
+    goto retry_getglyphs;
+  }
+  if (FAILED (hr))
+  {
+    FAIL ("Analyzer failed to get glyphs.");
+    return false;
+  }
+
+  float* glyphAdvances = (float*) malloc (maxGlyphCount * sizeof (float));
+  DWRITE_GLYPH_OFFSET* glyphOffsets = (DWRITE_GLYPH_OFFSET*)
+    malloc(maxGlyphCount * sizeof (DWRITE_GLYPH_OFFSET));
+
+  /* The -2 in the following is to compensate for possible
+   * alignment needed after the WORD array.  sizeof(WORD) == 2. */
+  unsigned int glyphs_size = (scratch_size * sizeof(int) - 2)
+         / (sizeof(WORD) +
+            sizeof(DWRITE_SHAPING_GLYPH_PROPERTIES) +
+            sizeof(int) +
+            sizeof(DWRITE_GLYPH_OFFSET) +
+            sizeof(uint32_t));
+  ALLOCATE_ARRAY (uint32_t, vis_clusters, glyphs_size);
+
+#undef ALLOCATE_ARRAY
+
+  int fontEmSize = font->face->get_upem();
+  if (fontEmSize < 0)
+    fontEmSize = -fontEmSize;
+
+  if (fontEmSize < 0)
+    fontEmSize = -fontEmSize;
+  double x_mult = (double) font->x_scale / fontEmSize;
+  double y_mult = (double) font->y_scale / fontEmSize;
+
+  hr = analyzer->GetGlyphPlacements (textString,
+    clusterMap, textProperties, textLength, glyphIndices,
+    glyphProperties, glyphCount, fontFace, fontEmSize,
+    FALSE, isRightToLeft, &runHead->mScript, localeName,
+    &dwFeatures, featureRangeLengths, 1,
+    glyphAdvances, glyphOffsets);
+
+  if (FAILED (hr))
+  {
+    FAIL ("Analyzer failed to get glyph placements.");
+    return false;
+  }
+
+  IDWriteTextAnalyzer1* analyzer1;
+  analyzer->QueryInterface (&analyzer1);
+
+  if (analyzer1 && lineWidth)
+  {
+
+    DWRITE_JUSTIFICATION_OPPORTUNITY* justificationOpportunities =
+      (DWRITE_JUSTIFICATION_OPPORTUNITY*)
+      malloc (maxGlyphCount * sizeof (DWRITE_JUSTIFICATION_OPPORTUNITY));
+    hr = analyzer1->GetJustificationOpportunities (fontFace, fontEmSize,
+      runHead->mScript, textLength, glyphCount, textString, clusterMap,
+      glyphProperties, justificationOpportunities);
+
+    if (FAILED (hr))
+    {
+      FAIL ("Analyzer failed to get justification opportunities.");
+      return false;
+    }
+
+    float* justifiedGlyphAdvances =
+      (float*) malloc (maxGlyphCount * sizeof (float));
+    DWRITE_GLYPH_OFFSET* justifiedGlyphOffsets = (DWRITE_GLYPH_OFFSET*)
+      malloc (glyphCount * sizeof (DWRITE_GLYPH_OFFSET));
+    hr = analyzer1->JustifyGlyphAdvances (lineWidth, glyphCount, justificationOpportunities,
+      glyphAdvances, glyphOffsets, justifiedGlyphAdvances, justifiedGlyphOffsets);
+
+    if (FAILED (hr))
+    {
+      FAIL("Analyzer failed to get justified glyph advances.");
+      return false;
+    }
+
+    DWRITE_SCRIPT_PROPERTIES scriptProperties;
+    hr = analyzer1->GetScriptProperties (runHead->mScript, &scriptProperties);
+    if (FAILED (hr))
+    {
+      FAIL("Analyzer failed to get script properties.");
+      return false;
+    }
+    uint32_t justificationCharacter = scriptProperties.justificationCharacter;
+
+    // if a script justificationCharacter is not space, it can have GetJustifiedGlyphs
+    if (justificationCharacter != 32)
+    {
+      uint16_t* modifiedClusterMap = (uint16_t*) malloc (textLength * sizeof (uint16_t));
+    retry_getjustifiedglyphs:
+      uint16_t* modifiedGlyphIndices = (uint16_t*) malloc (maxGlyphCount * sizeof (uint16_t));
+      float* modifiedGlyphAdvances = (float*) malloc (maxGlyphCount * sizeof (float));
+      DWRITE_GLYPH_OFFSET* modifiedGlyphOffsets = (DWRITE_GLYPH_OFFSET*)
+        malloc (maxGlyphCount * sizeof (DWRITE_GLYPH_OFFSET));
+      uint32_t actualGlyphsCount;
+      hr = analyzer1->GetJustifiedGlyphs (fontFace, fontEmSize, runHead->mScript,
+        textLength, glyphCount, maxGlyphCount, clusterMap, glyphIndices,
+        glyphAdvances, justifiedGlyphAdvances, justifiedGlyphOffsets,
+        glyphProperties, &actualGlyphsCount, modifiedClusterMap, modifiedGlyphIndices,
+        modifiedGlyphAdvances, modifiedGlyphOffsets);
+
+      if (hr == HRESULT_FROM_WIN32 (ERROR_INSUFFICIENT_BUFFER))
+      {
+        maxGlyphCount = actualGlyphsCount;
+        free (modifiedGlyphIndices);
+        free (modifiedGlyphAdvances);
+        free (modifiedGlyphOffsets);
+
+        maxGlyphCount = actualGlyphsCount;
+
+        goto retry_getjustifiedglyphs;
+      }
+      if (FAILED (hr))
+      {
+        FAIL ("Analyzer failed to get justified glyphs.");
+        return false;
+      }
+
+      free (clusterMap);
+      free (glyphIndices);
+      free (glyphAdvances);
+      free (glyphOffsets);
+
+      glyphCount = actualGlyphsCount;
+      clusterMap = modifiedClusterMap;
+      glyphIndices = modifiedGlyphIndices;
+      glyphAdvances = modifiedGlyphAdvances;
+      glyphOffsets = modifiedGlyphOffsets;
+
+      free (justifiedGlyphAdvances);
+      free (justifiedGlyphOffsets);
+    }
+    else
+    {
+      free (glyphAdvances);
+      free (glyphOffsets);
+
+      glyphAdvances = justifiedGlyphAdvances;
+      glyphOffsets = justifiedGlyphOffsets;
+    }
+
+    free (justificationOpportunities);
+
+  }
+
+  /* Ok, we've got everything we need, now compose output buffer,
+   * very, *very*, carefully! */
+
+  /* Calculate visual-clusters.  That's what we ship. */
+  for (unsigned int i = 0; i < glyphCount; i++)
+    vis_clusters[i] = -1;
+  for (unsigned int i = 0; i < buffer->len; i++)
+  {
+    uint32_t *p =
+      &vis_clusters[log_clusters[buffer->info[i].utf16_index()]];
+    *p = MIN (*p, buffer->info[i].cluster);
+  }
+  for (unsigned int i = 1; i < glyphCount; i++)
+    if (vis_clusters[i] == -1)
+      vis_clusters[i] = vis_clusters[i - 1];
+
+#undef utf16_index
+
+  if (unlikely (!buffer->ensure (glyphCount)))
+    FAIL ("Buffer in error");
+
+#undef FAIL
+
+  /* Set glyph infos */
+  buffer->len = 0;
+  for (unsigned int i = 0; i < glyphCount; i++)
+  {
+    hb_glyph_info_t *info = &buffer->info[buffer->len++];
+
+    info->codepoint = glyphIndices[i];
+    info->cluster = vis_clusters[i];
+
+    /* The rest is crap.  Let's store position info there for now. */
+    info->mask = glyphAdvances[i];
+    info->var1.i32 = glyphOffsets[i].advanceOffset;
+    info->var2.i32 = glyphOffsets[i].ascenderOffset;
+  }
+
+  /* Set glyph positions */
+  buffer->clear_positions ();
+  for (unsigned int i = 0; i < glyphCount; i++)
+  {
+    hb_glyph_info_t *info = &buffer->info[i];
+    hb_glyph_position_t *pos = &buffer->pos[i];
+
+    /* TODO vertical */
+    pos->x_advance = x_mult * (int32_t) info->mask;
+    pos->x_offset =
+      x_mult * (isRightToLeft ? -info->var1.i32 : info->var1.i32);
+    pos->y_offset = y_mult * info->var2.i32;
+  }
+
+  if (isRightToLeft)
+    hb_buffer_reverse (buffer);
+
+  free (clusterMap);
+  free (glyphIndices);
+  free (textProperties);
+  free (glyphProperties);
+  free (glyphAdvances);
+  free (glyphOffsets);
+
+  if (num_features)
+    free (singleFeatures.features);
+
+  /* Wow, done! */
+  return true;
+}
+
+hb_bool_t
+_hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
+  hb_font_t          *font,
+  hb_buffer_t        *buffer,
+  const hb_feature_t *features,
+  unsigned int        num_features)
+{
+  return _hb_directwrite_shape_full(shape_plan, font, buffer,
+    features, num_features, 0);
+}
+
+/*
+ * Public [experimental] API
+ */
+
+hb_bool_t
+hb_shape_dwrite_experimental_width(hb_font_t          *font,
+  hb_buffer_t        *buffer,
+  const hb_feature_t *features,
+  unsigned int        num_features,
+  float               width)
+{
+  static char *shapers = "directwrite";
+  hb_shape_plan_t *shape_plan = hb_shape_plan_create_cached (font->face,
+    &buffer->props, features, num_features, &shapers);
+  hb_bool_t res = _hb_directwrite_shape_full (shape_plan, font, buffer,
+    features, num_features, width);
+
+  if (res)
+    buffer->content_type = HB_BUFFER_CONTENT_TYPE_GLYPHS;
+
+  return res;
+}