internal void GetShapeableText(
CharacterBufferReference characterBufferReference,
int stringLength,
TextRunProperties textRunProperties,
CultureInfo digitCulture,
bool isRightToLeftParagraph,
IList<TextShapeableSymbols> shapeableList,
IShapeableTextCollector collector,
TextFormattingMode textFormattingMode
)
{
SpanVector<int> cachedScaledTypefaceIndexSpans;
int ichItem = 0;
CharacterBufferRange unicodeString = new CharacterBufferRange(
characterBufferReference,
stringLength
);
CultureInfo culture = textRunProperties.CultureInfo;
IList<Span> spans;
GCHandle gcHandle;
IntPtr ptext = characterBufferReference.CharacterBuffer.PinAndGetCharacterPointer(characterBufferReference.OffsetToFirstChar, out gcHandle);
// Contextual number substitution cannot be performed on the run level, since it depends
// on context - nearest preceding strong character. For this reason, contextual number
// substitutions has been already done (TextStore.CreateLSRunsUniformBidiLevel) and
// digitCulture has been updated to reflect culture which is dependent on the context.
// NumberSubstitutionMethod.AsCulture method can be resolved to Context, hence it also needs to be resolved to appropriate
// not ambiguous method.
// Both of those values (Context and AsCulture) are resolved to one of following: European, Traditional or NativeNational,
// which can be safely handled by DWrite without getting context information.
bool ignoreUserOverride;
NumberSubstitutionMethod numberSubstitutionMethod = DigitState.GetResolvedSubstitutionMethod(textRunProperties, digitCulture, out ignoreUserOverride);
// Itemize the text based on DWrite's text analysis for scripts and number substitution.
unsafe
{
checked
{
spans = MS.Internal.Text.TextInterface.TextAnalyzer.Itemize(
(ushort*)ptext.ToPointer(),
(uint)stringLength,
culture,
MS.Internal.FontCache.DWriteFactory.Instance,
isRightToLeftParagraph,
digitCulture,
ignoreUserOverride,
(uint)numberSubstitutionMethod,
ClassificationUtility.Instance,
UnsafeNativeMethods.CreateTextAnalysisSink,
UnsafeNativeMethods.GetScriptAnalysisList,
UnsafeNativeMethods.GetNumberSubstitutionList,
UnsafeNativeMethods.CreateTextAnalysisSource
);
}
}
characterBufferReference.CharacterBuffer.UnpinCharacterPointer(gcHandle);
SpanVector itemSpans = new SpanVector(null, new FrugalStructList<Span>((ICollection<Span>)spans));
cachedScaledTypefaceIndexSpans = new SpanVector<int>(-1);
foreach(Span itemSpan in itemSpans)
{
MapItem(
new CharacterBufferRange(
unicodeString,
ichItem,
itemSpan.length
),
culture,
itemSpan,
ref cachedScaledTypefaceIndexSpans,
ichItem
);
#if DEBUG
ValidateMapResult(
ichItem,
itemSpan.length,
ref cachedScaledTypefaceIndexSpans
);
#endif
ichItem += itemSpan.length;
}
Debug.Assert(ichItem == unicodeString.Length);
// intersect item spans with shapeable spans to create span of shapeable runs
int ich = 0;
SpanRider itemSpanRider = new SpanRider(itemSpans);
SpanRider<int> typefaceIndexSpanRider = new SpanRider<int>(cachedScaledTypefaceIndexSpans);
while(ich < unicodeString.Length)
{
itemSpanRider.At(ich);
typefaceIndexSpanRider.At(ich);
int index = typefaceIndexSpanRider.CurrentValue;
Debug.Assert(index >= 0);
int cch = unicodeString.Length - ich;
cch = Math.Min(cch, itemSpanRider.Length);
cch = Math.Min(cch, typefaceIndexSpanRider.Length);
ScaledShapeTypeface scaledShapeTypeface = _cachedScaledTypefaces[index];
collector.Add(
shapeableList,
new CharacterBufferRange(
unicodeString,
ich,
cch
),
textRunProperties,
(MS.Internal.Text.TextInterface.ItemProps)itemSpanRider.CurrentElement,
scaledShapeTypeface.ShapeTypeface,
scaledShapeTypeface.ScaleInEm,
scaledShapeTypeface.NullShape,
textFormattingMode
);
ich += cch;
}
}
/// <summary>
/// Cache index to the list of scaled shapeable typeface
/// </summary>
private void CacheScaledTypefaceMap(
CharacterBufferRange unicodeString,
CultureInfo culture,
CultureInfo digitCulture,
SpanVector scaledTypefaceSpans,
ref SpanVector<int> cachedScaledTypefaceIndexSpans,
int ichItem
)
{
IntMap map;
if (!_intMaps.TryGetValue(culture, out map))
{
map = new IntMap();
_intMaps.Add(culture, map);
}
DigitMap digitMap = new DigitMap(digitCulture);
SpanRider typefaceSpanRider = new SpanRider(scaledTypefaceSpans);
int ich = 0;
while(ich < unicodeString.Length)
{
typefaceSpanRider.At(ich);
int cch = Math.Min(unicodeString.Length - ich, typefaceSpanRider.Length);
int index = IndexOfScaledTypeface((ScaledShapeTypeface)typefaceSpanRider.CurrentElement);
Debug.Assert(index >= 0, "Invalid scaled shapeable typeface index spans");
cachedScaledTypefaceIndexSpans.Set(ichItem + ich, cch, index);
// we keep index + 1 in the map, so that we leave map entry zero
// to indicate uninitialized entry.
index++;
int sizeofChar;
for (int c = 0; c < cch; c += sizeofChar)
{
int ch = digitMap[
Classification.UnicodeScalar(
new CharacterBufferRange(unicodeString, ich + c, unicodeString.Length - ich - c),
out sizeofChar
)
];
// only cache typeface map index for base characters
if(!Classification.IsCombining(ch) && !Classification.IsJoiner(ch))
{
// Dump values of local variables when the condition fails for better debuggability.
// We use "if" to avoid the expensive string.Format() in normal case.
if (map[ch] != 0 && map[ch] != index)
{
Invariant.Assert(
false,
string.Format(
CultureInfo.InvariantCulture,
"shapeable cache stores conflicting info, ch = {0}, map[ch] = {1}, index = {2}",
ch, map[ch], index
)
);
}
map[ch] = (ushort)index;
}
}
ich += cch;
}
}
private unsafe void ValidateMapResult(
int ichRange,
int cchRange,
ref SpanVector<int> cachedScaledTypefaceIndexSpans
)
{
int ich = 0;
SpanRider<int> typefaceIndexSpanRider = new SpanRider<int>(cachedScaledTypefaceIndexSpans);
while(ich < cchRange)
{
typefaceIndexSpanRider.At(ichRange + ich);
if((int)typefaceIndexSpanRider.CurrentValue < 0)
{
Debug.Assert(false, "Invalid font face spans");
return;
}
int cch = Math.Min(cchRange - ich, typefaceIndexSpanRider.Length);
ich += cch;
}
}
/// <summary>
/// Map internal LSCP to text source cp
/// </summary>
internal int GetExternalCp(int lscp)
{
if (lscp >= _metrics._lscpLim)
{
if (_collapsedRange != null)
return _collapsedRange.TextSourceCharacterIndex;
return _cpFirst + _metrics._cchLength;
}
int offsetToFirstCp;
SpanRider plsrunSpanRider = new SpanRider(_plsrunVector);
// skip lscp until we find one with valid map
do
{
plsrunSpanRider.At(lscp - _cpFirst);
offsetToFirstCp = GetRun(((Plsrun)plsrunSpanRider.CurrentElement)).OffsetToFirstCp;
} while(offsetToFirstCp < 0 && ++lscp < _metrics._lscpLim);
return offsetToFirstCp + lscp - plsrunSpanRider.CurrentSpanStart;
}
/// <summary>
/// Compute bounds of runs within the specified range of lscp
/// </summary>
private IList<TextRunBounds> CalculateTextRunBounds(int lscpFirst, int lscpEnd)
{
if (lscpEnd <= lscpFirst)
{
// It is possible that we'll get a legitimate case when lscpFirst is
// actually greater. That's what happen when the client hittest a hidden
// run that follows a reverse block. Since it is a hidden run, LS has
// to yield the closest non-hidden place which may be the run preceding
// the hidden text. (wchao, PS bug #930976)
return null;
}
int lscp = lscpFirst;
int cchLeft = lscpEnd - lscpFirst;
SpanRider plsrunSpanRider = new SpanRider(_plsrunVector);
Point position = new Point(0, 0);
IList<TextRunBounds> boundsList = new List<TextRunBounds>(2);
while(cchLeft > 0)
{
plsrunSpanRider.At(lscp - _cpFirst);
Plsrun plsrun = (Plsrun)plsrunSpanRider.CurrentElement;
int cch = Math.Min(plsrunSpanRider.Length, cchLeft);
if(TextStore.IsContent(plsrun))
{
LSRun lsrun = GetRun(plsrun);
if( lsrun.Type == Plsrun.Text
|| lsrun.Type == Plsrun.InlineObject)
{
int cp = GetExternalCp(lscp);
int cchBounds = cch;
if ( HasCollapsed
&& _collapsedRange != null
&& cp <= _collapsedRange.TextSourceCharacterIndex
&& cp + cchBounds >= _collapsedRange.TextSourceCharacterIndex
&& cp + cchBounds < _collapsedRange.TextSourceCharacterIndex + _collapsedRange.Length)
{
// Limit the run bounds to only non-collapsed text,
// we deal with collapsed text separately as it might have different flow direction.
cchBounds = _collapsedRange.TextSourceCharacterIndex - cp;
}
if (cchBounds > 0)
{
TextRunBounds bounds = new TextRunBounds(
LSRun.RectUV(
position,
new LSPOINT(
LSLineUToParagraphU(
DistanceFromCharacterHit(new CharacterHit(cp, 0))
),
_metrics._baselineOffset - lsrun.BaselineOffset + lsrun.BaselineMoveOffset
),
new LSPOINT(
LSLineUToParagraphU(
DistanceFromCharacterHit(new CharacterHit(cp + cchBounds - 1, 1))
),
_metrics._baselineOffset - lsrun.BaselineOffset + lsrun.BaselineMoveOffset + lsrun.Height
),
this
),
cp,
cp + cchBounds,
lsrun.TextRun
);
boundsList.Add(bounds);
}
}
}
cchLeft -= cch;
lscp += cch;
}
return boundsList.Count > 0 ? boundsList : null;
}
/// <summary>
/// Search from the given lscp (inclusive) towards the specified direction for the
/// closest navigable cp. Return true is one such cp is found, false otherwise.
/// </summary>
private bool FindNextOrPreviousVisibleCp(
int lscp,
CaretDirection direction,
out int lscpVisisble
)
{
lscpVisisble = lscp;
SpanRider plsrunSpanRider = new SpanRider(_plsrunVector);
if (direction == CaretDirection.Forward)
{
while (lscpVisisble < _metrics._lscpLim)
{
plsrunSpanRider.At(lscpVisisble - _cpFirst);
LSRun run = GetRun((Plsrun) plsrunSpanRider.CurrentElement);
// When scanning forward, only trailine edges of visiable content are navigable.
if (run.IsVisible)
{
return true;
}
lscpVisisble += plsrunSpanRider.Length; // move to start of next span
}
}
else
{
Debug.Assert(direction == CaretDirection.Backward || direction == CaretDirection.Backspace);
// lscpCurrent can be right after the end of the line, we snap it back to be at the end of the line.
lscpVisisble = Math.Min(lscpVisisble, _metrics._lscpLim - 1);
while (lscpVisisble >= _cpFirst)
{
plsrunSpanRider.At(lscpVisisble - _cpFirst);
LSRun run = GetRun((Plsrun) plsrunSpanRider.CurrentElement);
// When scanning backward, visiable content has caret stop at its leading edge.
if (run.IsVisible)
{
return true;
}
// When scanning backward, the newline sequence has caret stop at its leading edge.
if (run.IsNewline)
{
// set navigable cp at the start of newline sequence.
lscpVisisble = _cpFirst + plsrunSpanRider.CurrentSpanStart;
return true;
}
lscpVisisble = _cpFirst + plsrunSpanRider.CurrentSpanStart - 1; // move to the end of previous span
}
}
lscpVisisble = lscp;
return false;
}