internal TextParagraphCache(
FormatSettings settings,
int firstCharIndex,
int paragraphWidth
)
{
Invariant.Assert(settings != null);
// create full text
_finiteFormatWidth = settings.GetFiniteFormatWidth(paragraphWidth);
_fullText = FullTextState.Create(settings, firstCharIndex, _finiteFormatWidth);
// acquiring LS context
TextFormatterContext context = settings.Formatter.AcquireContext(_fullText, IntPtr.Zero);
_fullText.SetTabs(context);
IntPtr ploparabreakValue = IntPtr.Zero;
LsErr lserr = context.CreateParaBreakingSession(
firstCharIndex,
_finiteFormatWidth,
// breakrec is not needed before the first cp of para cache
// since we handle Bidi break ourselves.
IntPtr.Zero,
ref ploparabreakValue,
ref _penalizedAsJustified
);
// get the exception in context before it is released
Exception callbackException = context.CallbackException;
// release the context
context.Release();
if(lserr != LsErr.None)
{
GC.SuppressFinalize(this);
if(callbackException != null)
{
// rethrow exception thrown in callbacks
throw new InvalidOperationException(SR.Get(SRID.CreateParaBreakingSessionFailure, lserr), callbackException);
}
else
{
// throw with LS error codes
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CreateParaBreakingSessionFailure, lserr), lserr);
}
}
_ploparabreak.Value = ploparabreakValue;
// keep context alive till here
GC.KeepAlive(context);
}
private FullTextBreakpoint(
FullTextState fullText,
int firstCharIndex,
int maxLineWidth,
ref LsBreaks lsbreaks,
int breakIndex
) : this()
{
// According to antons: PTS only uses the width of a feasible break to avoid
// clipping in subpage. At the moment, there is no good solution as of how
// PTS client would be able to compute this width efficiently using LS.
// The work around - although could be conceived would simply be too slow.
// The width should therefore be set to the paragraph width for the time being.
//
// Client of text formatter would simply pass the value of TextBreakpoint.Width
// back to PTS pfnFormatLineVariants call.
LsLineWidths lineWidths = new LsLineWidths();
lineWidths.upLimLine = maxLineWidth;
lineWidths.upStartMainText = fullText.TextStore.Settings.TextIndent;
lineWidths.upStartMarker = lineWidths.upStartMainText;
lineWidths.upStartTrailing = lineWidths.upLimLine;
lineWidths.upMinStartTrailing = lineWidths.upStartTrailing;
// construct the correspondent text metrics
unsafe
{
_metrics.Compute(
fullText,
firstCharIndex,
maxLineWidth,
null, // collapsingSymbol
ref lineWidths,
&lsbreaks.plslinfoArray[breakIndex]
);
_ploline = new SecurityCriticalDataForSet <IntPtr>(lsbreaks.pplolineArray[breakIndex]);
// keep the line penalty handle
_penaltyResource = new SecurityCriticalDataForSet <IntPtr>(lsbreaks.plinepenaltyArray[breakIndex]);
if (lsbreaks.plslinfoArray[breakIndex].fForcedBreak != 0)
{
_isLineTruncated = true;
}
}
}
private double _pixelsPerDip; // PixelsPerDip
/// <summary>
/// Construct text metrics from full text info
/// </summary>
/// <remarks>
///
/// When the application formats a line of text. It starts from the leading edge of the paragraph - the reference position
/// called "Paragraph Start". It gives the width of the paragraph or "Paragraph Width" to TextFormatter as one of the main
/// parameters to TextFormatter.FormatLine method. It may also provide additional info about how it wants the line to look
/// like. The following are all of such info and how the formatting process is carried on inside TextFormatter.
///
///
/// *** Indent/Paragraph Indent ***
/// The application may specify "Indent" - the distance from the beginning of the line to the beginning of the text in that
/// line. The value is sent to TextFormatter via [TextParagraphProperties.Indent]. It may also specify "Paragraph Indent"
/// - the distance from the beginning of the paragraph to the beginning of the line [TextParagraphProperties.ParagraphIndent].
/// The usage of paragraph indent is to offset the beginning of the line relative to the paragraph starting point, while
/// indent is to offset the beginning of text realtive to the line starting point. Paragraph indent is not included as part
/// of the line width while indent is.
///
///
/// *** Text Alignment ***
/// "Text Alignment" [TextParagraphProperties.TextAlignment] may be specified to align the leading, center or trailing edge
/// of the line to the leading, center or trailing edge of the paragraph excluding paragraph indent.
///
///
/// *** Bullet/Auto-numbering ***
/// The application may also specify "bullet" (or "marker") for the line. Marker does not affect the layout measurement of the
/// line. Line with marker has the same line width with the line that has not. The presence of marker however affects the
/// pixel-wise black width of the line. The application specifies the distance from the beginning of the line to the trailing
/// edge of the marker symbol via the property [TextMarkerProperties.Offset]. The application can create the visual effect of
/// having marker embedded inside the body of paragraph text (so-called "marker inside") by specifying a positive indent so
/// that the text starts after the beginning of the line and a positive smaller amount of marker offset to place the marker
/// symbol at between the beginning of the line and the beginning of the text. The "marker outside" visual effect can
/// also be achieved in a similar manner by specifying zero or positive indent value with negative marker offset value.
///
///
/// *** Formatted Line Properties ***
/// Once the line formatting process is completed and a line is returned to the application. The application determines the
/// distance from the paragraph starting point to the actual beginning of the line by looking at the "Line Start" property of
/// the text line [TextLine.Start]. The "Width" of the line can be determined, naturally, from the property [TextLine.Width].
/// The property value [TextLine.OverhangLeading] represents the distance from the beginning of the line, or the line's alignment
/// point, to the first leading pixel of that line so-called the "Black Start". The property [TextLine.OverhangTrailing]
/// is the distance from the last trailing pixel of the line to the trailing edge alignment point of the line. The application
/// uses these "overhang" or "overshoot" values to ensure proper positioning of text that avoids pixel clipping of the
/// glyph image. A less sophisticated application may provide reasonable leading and trailing margin around the text line
/// and ignores these properties altogether.
///
///
/// *** Hit-Testing ***
/// The application may also perform hit-testing by calling methods on TextLine. All the distances involved in hit-testing
/// operations are distances from the paragraph start, not from the line start. Marker symbol on its own is not hit-testable.
///
///
/// *** Tabs ***
/// The application may specify tab stops - an array of positions to where text aligns. Each tab stop may have different
/// "Tab Alignment". The left, center and right tab alignment aligns the tab stop position to the leading, center and the
/// trailing edge of the text following the tab character. "Tab Leader" may also be specified to fill the distance occupied
/// by the presence of tab character with the symbol of choice. Tab stops is specified thru the property [TextParagraph.Tabs].
/// In the absence of tab stops, the application may assume an automatic tab stop - so called "Incremental Tab" specified by
/// the property [TextParagraphProperties.DefaultIncrementalTab]. The property could be overridden, by default the value
/// is set by TextFormatter to 4 em of the paragraph's default font.
///
///
/// *** Line Services Properties ***
/// TextFormatter relies on LS to calculate the distance from the beginning of the line to the beginning of text or "Text Start"
/// and keep it in the private property [this._textStart]. This value is non-zero when 1) the line starts with indentation or
/// 2) the line starts with marker - either bullet or auto-numbering symbol.
///
/// In case of the line with marker, LS also produces the distance from the beginning of the line to the beginning of the marker
/// symbol, but TextFormatter does not retain that distance because marker is outside the line. The application is assumed
/// responsibility to make sure the marker symbol is not going to be clipped out. The application achieves that by manipulating
/// the indent value along with the marker offset value.
///
/// TextFormatter also retains the total "Text Width" value computed by LS in the private property [this._textWidth]. This
/// is the distance from the beginning of the text to the end including all trailing whitespaces at the end of the line. The
/// similar value but with trailing whitespaces excluded is kept in the private property [this._textWidthAtTrailing].
///
/// TextFormatter starts formatting a LS line by assuming the beginning of the line being at an imaginary origin. It then
/// places the starting point of the content depending on whether the line has either marker symbol or indent. The actual
/// mechanism for the placement is in FetchLineProps callback where the value [LsLineProps.durLeft] represents the distance
/// relative to the line's origin where actual content begins. The distances can either be positive or negative. Negative
/// distance runs in the reverse direction from the direction of text flow. When a negative indent or marker offset is
/// specified, durLeft is set to negative distance relative to line start.
///
/// TextFormatter however does not rely on LS for the whole line's text alignment. It always formats LS as if the line is
/// left-aligned. Once the distances of the line are received, it aligns the whole line according to the text alignment setting
/// specified by the application, outside the LS call. The result of this aligning process is a distance from the beginning of
/// the paragraph to the beginning of text and is kept in a private property [this._paragraphToText].
///
/// </remarks>
internal unsafe void Compute(
FullTextState fullText,
int firstCharIndex,
int paragraphWidth,
FormattedTextSymbols collapsingSymbol,
ref LsLineWidths lineWidths,
LsLInfo *plsLineInfo
)
{
_formatter = fullText.Formatter;
TextStore store = fullText.TextStore;
_pixelsPerDip = store.Settings.TextSource.PixelsPerDip;
// obtain position of important distances
_textStart = lineWidths.upStartMainText;
_textWidthAtTrailing = lineWidths.upStartTrailing;
_textWidth = lineWidths.upLimLine;
// append line end collapsing symbol if any
if (collapsingSymbol != null)
{
AppendCollapsingSymbolWidth(TextFormatterImp.RealToIdeal(collapsingSymbol.Width));
}
// make all widths relative to text start
_textWidth -= _textStart;
_textWidthAtTrailing -= _textStart;
// keep the newline character count if any
_cchNewline = store.CchEol;
// count text and dependant characters
_lscpLim = plsLineInfo->cpLimToContinue;
_lastRun = fullText.CountText(_lscpLim, firstCharIndex, out _cchLength);
Debug.Assert(_cchLength > 0);
if (plsLineInfo->endr != LsEndRes.endrEndPara &&
plsLineInfo->endr != LsEndRes.endrSoftCR)
{
// endrEndPara denotes that the line ends at paragraph end. It is a result of submitting Paragraph Separator to LS.
// endrSoftCR denotes end of line but not end of paragraph. This is a result of submitting Line Separator to LS.
_cchNewline = 0;
if (plsLineInfo->dcpDepend >= 0)
{
// According to SergeyGe [2/16/2006], dcpDepend reported from LS cannot made precise when considering
// the line ending with hyphenation - this is because LS does not have the knowledge about the amount
// of text, after the hyphenation point, being examined by its client during the process of finding
// the right place to hyphenate. LS client must therefore take into account the number of lookahead
// LSCP examined by hyphenator when computing the correct dcpDepend for the line. In our implementation
// it would just mean we take the max of the two values.
int lscpFirstIndependence = Math.Max(
plsLineInfo->cpLimToContinue + plsLineInfo->dcpDepend,
fullText.LscpHyphenationLookAhead
);
fullText.CountText(lscpFirstIndependence, firstCharIndex, out _cchDepend);
_cchDepend -= _cchLength;
}
}
ParaProp pap = store.Pap;
if (_height <= 0)
{
// if height has not been settled,
// calculate line height and baseline offset
if (pap.LineHeight > 0)
{
// Host specifies line height, honor it.
_height = pap.LineHeight;
_baselineOffset = (int)Math.Round(
_height
* pap.DefaultTypeface.Baseline(pap.EmSize, Constants.DefaultIdealToReal, _pixelsPerDip, fullText.TextFormattingMode)
/ pap.DefaultTypeface.LineSpacing(pap.EmSize, Constants.DefaultIdealToReal, _pixelsPerDip, fullText.TextFormattingMode)
);
}
if (plsLineInfo->dvrMultiLineHeight == int.MaxValue)
{
// Line is empty so text height and text baseline are based on the default typeface;
// it doesn't make sense even for an emtpy line to have zero text height
_textAscent = (int)Math.Round(pap.DefaultTypeface.Baseline(pap.EmSize, Constants.DefaultIdealToReal, _pixelsPerDip, fullText.TextFormattingMode));
_textHeight = (int)Math.Round(pap.DefaultTypeface.LineSpacing(pap.EmSize, Constants.DefaultIdealToReal, _pixelsPerDip, fullText.TextFormattingMode));
}
else
{
_textAscent = plsLineInfo->dvrAscent;
_textHeight = _textAscent + plsLineInfo->dvrDescent;
if (fullText.VerticalAdjust)
{
// Line requires vertical repositioning of text runs
store.AdjustRunsVerticalOffset(
plsLineInfo->cpLimToContinue - firstCharIndex,
_height,
_baselineOffset,
out _textHeight,
out _textAscent
);
}
}
// if the client hasn't specified a line height then the line height and baseline
// are the same as the text height and text baseline
if (_height <= 0)
{
_height = _textHeight;
_baselineOffset = _textAscent;
}
}
// Text alignment aligns the line to correspondent paragraph alignment start edge
switch (pap.Align)
{
case TextAlignment.Right:
// alignment rule:
// "The sum of paragraph start to line start and line width is equal to paragraph width"
//
// PTL + LW = PW
// (PTT - LTT) + (LTT + TW) = PW
// (thus) PTT = PW - TW
_paragraphToText = paragraphWidth - _textWidthAtTrailing;
break;
case TextAlignment.Center:
// alignment rule:
// "The sum of paragraph start to line start and half the line width is equal to half the paragraph width"
//
// PTL + 0.5*LW = 0.5*PW
// (PTT - LTT) + 0.5*(LTT + TW) = 0.5*PW
// (thus) PTT = 0.5 * (PW + LTT - TW)
_paragraphToText = (int)Math.Round((paragraphWidth + _textStart - _textWidthAtTrailing) * 0.5);
break;
default:
// alignment rule:
// "Paragraph start to line start is paragraph indent"
//
// PTL = PI
// PTT - LTT = PI
// (thus) PTT = PI + LTT
_paragraphToText = pap.ParagraphIndent + _textStart;
break;
}
}
private void FormatLine(
FullTextState fullText,
int cpFirst,
int lineLength,
int formatWidth,
int finiteFormatWidth,
int paragraphWidth,
LineFlags lineFlags,
FormattedTextSymbols collapsingSymbol
)
{
_metrics._formatter = fullText.Formatter;
Debug.Assert(_metrics._formatter != null);
TextStore store = fullText.TextStore;
TextStore markerStore = fullText.TextMarkerStore;
FormatSettings settings = store.Settings;
ParaProp pap = settings.Pap;
_paragraphTextDecorations = pap.TextDecorations;
if (_paragraphTextDecorations != null)
{
if (_paragraphTextDecorations.Count != 0)
{
_defaultTextDecorationsBrush = pap.DefaultTextDecorationsBrush;
}
else
{
_paragraphTextDecorations = null;
}
}
// acquiring LS context
TextFormatterContext context = _metrics._formatter.AcquireContext(fullText, IntPtr.Zero);
LsLInfo plslineInfo = new LsLInfo();
LsLineWidths lineWidths = new LsLineWidths();
fullText.SetTabs(context);
int lscpLineLength = 0; // line length in LSCP
if (lineLength > 0)
{
// line length is previously known (e.g. during optimal paragraph formatting),
// prefetch lsruns up to the specified line length.
lscpLineLength = PrefetchLSRuns(store, cpFirst, lineLength);
}
IntPtr ploline;
LsErr lserr = context.CreateLine(
cpFirst,
lscpLineLength,
formatWidth,
lineFlags,
IntPtr.Zero, // single-line formatting does not require break record
out ploline,
out plslineInfo,
out _depthQueryMax,
out lineWidths
);
// Did we exceed the LineServices maximum line width?
if (lserr == LsErr.TooLongParagraph)
{
// Determine where to insert a fake line break. FullTextState.CpMeasured
// is a reasonable estimate since we know the nominal widths up to that
// point fit within the margin.
int cpLimit = fullText.CpMeasured;
int subtract = 1;
for (;;)
{
// The line must contain at least one character position.
if (cpLimit < 1)
{
cpLimit = 1;
}
store.InsertFakeLineBreak(cpLimit);
lserr = context.CreateLine(
cpFirst,
lscpLineLength,
formatWidth,
lineFlags,
IntPtr.Zero, // single-line formatting does not require break record
out ploline,
out plslineInfo,
out _depthQueryMax,
out lineWidths
);
if (lserr != LsErr.TooLongParagraph || cpLimit == 1)
{
// We're done or can't chop off any more text.
break;
}
else
{
// Chop off more text and try again. Double the amount of
// text we chop off each time so we retry too many times.
cpLimit = fullText.CpMeasured - subtract;
subtract *= 2;
}
}
}
_ploline.Value = ploline;
// get the exception in context before it is released
Exception callbackException = context.CallbackException;
// release the context
context.Release();
if(lserr != LsErr.None)
{
GC.SuppressFinalize(this);
if(callbackException != null)
{
// rethrow exception thrown in callbacks
throw WrapException(callbackException);
}
else
{
// throw with LS error codes
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CreateLineFailure, lserr), lserr);
}
}
// keep context alive at least till here
GC.KeepAlive(context);
unsafe
{
// construct text metrics for the line
_metrics.Compute(
fullText,
cpFirst,
paragraphWidth,
collapsingSymbol,
ref lineWidths,
&plslineInfo
);
}
// keep record for min width as we may be formatting min/max
_textMinWidthAtTrailing = lineWidths.upMinStartTrailing - _metrics._textStart;
if (collapsingSymbol != null)
{
_collapsingSymbol = collapsingSymbol;
_textMinWidthAtTrailing += TextFormatterImp.RealToIdeal(collapsingSymbol.Width);
}
else
{
// overflow detection for potential collapsible line
if (_metrics._textStart + _metrics._textWidthAtTrailing > finiteFormatWidth)
{
bool hasOverflowed = true;
if (_textFormattingMode == TextFormattingMode.Display)
{
// apply display-mode rounding before checking for overflow
double realWidth = Width;
double realFormatWidth = _metrics._formatter.IdealToReal(finiteFormatWidth);
hasOverflowed = (TextFormatterImp.CompareReal(realWidth, realFormatWidth, _textFormattingMode) > 0);
}
if (hasOverflowed)
{
// line has overflowed
_statusFlags |= StatusFlags.HasOverflowed;
// let's keep the full text state around. We'll need it later for collapsing
_fullText = fullText;
}
}
}
if ( fullText != null
&& ( fullText.KeepState
|| (_statusFlags & StatusFlags.KeepState) != 0
)
)
{
// the state of full text is to be kept after formatting is done
_fullText = fullText;
}
// retain all line properties for interactive operations
_ploc = context.Ploc;
_cpFirst = cpFirst;
_paragraphWidth = paragraphWidth;
if (pap.RightToLeft)
_statusFlags |= StatusFlags.RightToLeft;
if (plslineInfo.fForcedBreak != 0)
_statusFlags |= StatusFlags.IsTruncated;
// retain the state of plsruns
_plsrunVector = store.PlsrunVector;
_lsrunsMainText = store.LsrunList;
if (markerStore != null)
_lsrunsMarkerText = markerStore.LsrunList;
// we store the text source in the line in case drawing code calls
// the TextSource to find out the text effect index.
//
_textSource = settings.TextSource;
}
internal static IList <TextBreakpoint> CreateMultiple(
TextParagraphCache paragraphCache,
int firstCharIndex,
int maxLineWidth,
TextLineBreak previousLineBreak,
IntPtr penaltyRestriction,
out int bestFitIndex
)
{
Invariant.Assert(paragraphCache != null);
// grab full text state from paragraph cache
FullTextState fullText = paragraphCache.FullText;
Invariant.Assert(fullText != null);
FormatSettings settings = fullText.TextStore.Settings;
Invariant.Assert(settings != null);
// update formatting parameters at line start
settings.UpdateSettingsForCurrentLine(
maxLineWidth,
previousLineBreak,
(firstCharIndex == fullText.TextStore.CpFirst)
);
Invariant.Assert(settings.Formatter != null);
// acquiring LS context
TextFormatterContext context = settings.Formatter.AcquireContext(fullText, IntPtr.Zero);
IntPtr previousBreakRecord = IntPtr.Zero;
if (settings.PreviousLineBreak != null)
{
previousBreakRecord = settings.PreviousLineBreak.BreakRecord.Value;
}
// need not consider marker as tab since marker does not affect line metrics and it wasnt drawn.
fullText.SetTabs(context);
LsBreaks lsbreaks = new LsBreaks();
LsErr lserr = context.CreateBreaks(
fullText.GetBreakpointInternalCp(firstCharIndex),
previousBreakRecord,
paragraphCache.Ploparabreak.Value, // para breaking session
penaltyRestriction,
ref lsbreaks,
out bestFitIndex
);
// get the exception in context before it is released
Exception callbackException = context.CallbackException;
// release the context
context.Release();
if (lserr != LsErr.None)
{
if (callbackException != null)
{
// rethrow exception thrown in callbacks
throw callbackException;
}
else
{
// throw with LS error codes
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CreateBreaksFailure, lserr), lserr);
}
}
// keep context alive at least till here
GC.KeepAlive(context);
TextBreakpoint[] breakpoints = new TextBreakpoint[lsbreaks.cBreaks];
for (int i = 0; i < lsbreaks.cBreaks; i++)
{
breakpoints[i] = new FullTextBreakpoint(
fullText,
firstCharIndex,
maxLineWidth,
ref lsbreaks,
i // the current break
);
}
return(breakpoints);
}
internal unsafe void Compute(
FullTextState fullText,
int firstCharIndex,
int paragraphWidth,
FormattedTextSymbols collapsingSymbol,
ref LsLineWidths lineWidths,
LsLInfo* plsLineInfo
)
{
_formatter = fullText.Formatter;
TextStore store = fullText.TextStore;
// obtain position of important distances
_textStart = lineWidths.upStartMainText;
_textWidthAtTrailing = lineWidths.upStartTrailing;
_textWidth = lineWidths.upLimLine;
// append line end collapsing symbol if any
if (collapsingSymbol != null)
{
AppendCollapsingSymbolWidth(TextFormatterImp.RealToIdeal(collapsingSymbol.Width));
}
// make all widths relative to text start
_textWidth -= _textStart;
_textWidthAtTrailing -= _textStart;
// keep the newline character count if any
_cchNewline = store.CchEol;
// count text and dependant characters
_lscpLim = plsLineInfo->cpLimToContinue;
_lastRun = fullText.CountText(_lscpLim, firstCharIndex, out _cchLength);
Debug.Assert(_cchLength > 0);
if ( plsLineInfo->endr != LsEndRes.endrEndPara
&& plsLineInfo->endr != LsEndRes.endrSoftCR)
{
// endrEndPara denotes that the line ends at paragraph end. It is a result of submitting Paragraph Separator to LS.
// endrSoftCR denotes end of line but not end of paragraph. This is a result of submitting Line Separator to LS.
_cchNewline = 0;
if (plsLineInfo->dcpDepend >= 0)
{
// According to SergeyGe [2/16/2006], dcpDepend reported from LS cannot made precise when considering
// the line ending with hyphenation - this is because LS does not have the knowledge about the amount
// of text, after the hyphenation point, being examined by its client during the process of finding
// the right place to hyphenate. LS client must therefore take into account the number of lookahead
// LSCP examined by hyphenator when computing the correct dcpDepend for the line. In our implementation
// it would just mean we take the max of the two values.
int lscpFirstIndependence = Math.Max(
plsLineInfo->cpLimToContinue + plsLineInfo->dcpDepend,
fullText.LscpHyphenationLookAhead
);
fullText.CountText(lscpFirstIndependence, firstCharIndex, out _cchDepend);
_cchDepend -= _cchLength;
}
}
ParaProp pap = store.Pap;
if (_height <= 0)
{
// if height has not been settled,
// calculate line height and baseline offset
if(pap.LineHeight > 0)
{
// Host specifies line height, honor it.
_height = pap.LineHeight;
_baselineOffset = (int)Math.Round(
_height
* pap.DefaultTypeface.Baseline(pap.EmSize, Constants.DefaultIdealToReal, Util.PixelsPerDip, fullText.TextFormattingMode)
/ pap.DefaultTypeface.LineSpacing(pap.EmSize, Constants.DefaultIdealToReal, Util.PixelsPerDip, fullText.TextFormattingMode)
);
}
if(plsLineInfo->dvrMultiLineHeight == int.MaxValue)
{
// Line is empty so text height and text baseline are based on the default typeface;
// it doesn't make sense even for an emtpy line to have zero text height
_textAscent = (int)Math.Round(pap.DefaultTypeface.Baseline(pap.EmSize, Constants.DefaultIdealToReal, Util.PixelsPerDip, fullText.TextFormattingMode));
_textHeight = (int)Math.Round(pap.DefaultTypeface.LineSpacing(pap.EmSize, Constants.DefaultIdealToReal, Util.PixelsPerDip, fullText.TextFormattingMode));
}
else
{
_textAscent = plsLineInfo->dvrAscent;
_textHeight = _textAscent + plsLineInfo->dvrDescent;
if (fullText.VerticalAdjust)
{
// Line requires vertical repositioning of text runs
store.AdjustRunsVerticalOffset(
plsLineInfo->cpLimToContinue - firstCharIndex,
_height,
_baselineOffset,
out _textHeight,
out _textAscent
);
}
}
// if the client hasn't specified a line height then the line height and baseline
// are the same as the text height and text baseline
if (_height <= 0)
{
_height = _textHeight;
_baselineOffset = _textAscent;
}
}
// Text alignment aligns the line to correspondent paragraph alignment start edge
switch(pap.Align)
{
case TextAlignment.Right:
// alignment rule:
// "The sum of paragraph start to line start and line width is equal to paragraph width"
//
// PTL + LW = PW
// (PTT - LTT) + (LTT + TW) = PW
// (thus) PTT = PW - TW
_paragraphToText = paragraphWidth - _textWidthAtTrailing;
break;
case TextAlignment.Center:
// alignment rule:
// "The sum of paragraph start to line start and half the line width is equal to half the paragraph width"
//
// PTL + 0.5*LW = 0.5*PW
// (PTT - LTT) + 0.5*(LTT + TW) = 0.5*PW
// (thus) PTT = 0.5 * (PW + LTT - TW)
_paragraphToText = (int)Math.Round((paragraphWidth + _textStart - _textWidthAtTrailing) * 0.5);
break;
default:
// alignment rule:
// "Paragraph start to line start is paragraph indent"
//
// PTL = PI
// PTT - LTT = PI
// (thus) PTT = PI + LTT
_paragraphToText = pap.ParagraphIndent + _textStart;
break;
}
}
private FullTextBreakpoint(
FullTextState fullText,
int firstCharIndex,
int maxLineWidth,
ref LsBreaks lsbreaks,
int breakIndex
) : this()
{
// According to antons: PTS only uses the width of a feasible break to avoid
// clipping in subpage. At the moment, there is no good solution as of how
// PTS client would be able to compute this width efficiently using LS.
// The work around - although could be conceived would simply be too slow.
// The width should therefore be set to the paragraph width for the time being.
//
// Client of text formatter would simply pass the value of TextBreakpoint.Width
// back to PTS pfnFormatLineVariants call.
LsLineWidths lineWidths = new LsLineWidths();
lineWidths.upLimLine = maxLineWidth;
lineWidths.upStartMainText = fullText.TextStore.Settings.TextIndent;
lineWidths.upStartMarker = lineWidths.upStartMainText;
lineWidths.upStartTrailing = lineWidths.upLimLine;
lineWidths.upMinStartTrailing = lineWidths.upStartTrailing;
// construct the correspondent text metrics
unsafe
{
_metrics.Compute(
fullText,
firstCharIndex,
maxLineWidth,
null, // collapsingSymbol
ref lineWidths,
&lsbreaks.plslinfoArray[breakIndex]
);
_ploline = new SecurityCriticalDataForSet<IntPtr>(lsbreaks.pplolineArray[breakIndex]);
// keep the line penalty handle
_penaltyResource = new SecurityCriticalDataForSet<IntPtr>(lsbreaks.plinepenaltyArray[breakIndex]);
if (lsbreaks.plslinfoArray[breakIndex].fForcedBreak != 0)
_isLineTruncated = true;
}
}