Code:
/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / Orcas / NetFXw7 / wpf / src / Core / CSharp / MS / Internal / Shaping / OpenTypeCommon.cs / 1 / OpenTypeCommon.cs
//+------------------------------------------------------------------------
//
// Microsoft Windows Client Platform
// Copyright (C) Microsoft Corporation, 2002
//
// File: Common.cs
//
// Contents: OpentTypeLayout higher level internal engine and structures
//
// contact: sergeym
//
// History: 2002-03-23 Created (sergeym)
//
//-----------------------------------------------------------------------
using System.Diagnostics;
using System.Security;
using System.Security.Permissions;
using System;
using System.IO;
using MS.Internal;
namespace MS.Internal.Shaping
{
///
/// Provide core layout functionality
///
internal static unsafe class LayoutEngine
{
///
/// Main layout loop. Execute lookups in right order for enabled ranges
///
/// In: Font access interface
/// In: Layout engine wokrspace
/// In: Layout table tag (GSUB or GPOS)
/// In: Layout Table (GSUB or GPOS)
/// In: Layout metrics
/// In: Language system table
/// In: FeatureList
/// In: Lookup list
/// In: List of feature to apply
/// In: Actual number of features in
/// Critical - calls critical code, accepts pointer parameters, unsafe code
///
[SecurityCritical]
public static void ApplyFeatures(
IOpenTypeFont Font,
OpenTypeLayoutWorkspace workspace,
OpenTypeTags TableTag,
FontTable Table,
LayoutMetrics Metrics,
LangSysTable LangSys,
FeatureList Features,
LookupList Lookups,
Feature[] FeatureSet,
int featureCount,
int featureSetOffset,
int CharCount,
UshortList Charmap,
GlyphInfoList GlyphInfo,
int* Advances,
LayoutOffset* Offsets
)
{
UpdateGlyphFlags(Font, GlyphInfo, 0, GlyphInfo.Length, false, GlyphFlags.NotChanged);
// if client did not supply us with workspace
// we will create our own (temporarily)
if (workspace == null)
{
workspace = new OpenTypeLayoutWorkspace();
}
ushort lookupCount=Lookups.LookupCount(Table);
//Compile feature set
CompileFeatureSet(
FeatureSet,
featureCount,
featureSetOffset,
CharCount,
Table,
LangSys,
Features,
lookupCount,
workspace
);
OpenTypeLayoutCache.InitCache(Font, TableTag, GlyphInfo, workspace);
for(ushort lookupIndex = 0; lookupIndex < lookupCount; lookupIndex++)
{
if (!workspace.IsAggregatedFlagSet(lookupIndex))
{
continue;
}
int firstChar=0,
afterLastChar=0,
firstGlyph=0,
afterLastGlyph=0;
OpenTypeLayoutCache.FindNextLookup(workspace,
GlyphInfo,
lookupIndex,
out lookupIndex,
out firstGlyph);
// We need to check this again, because FindNextLookup will change lookupIndex
if (lookupIndex >= lookupCount)
{
break;
}
if (!workspace.IsAggregatedFlagSet(lookupIndex))
{
continue;
}
LookupTable lookup = Lookups.Lookup(Table, lookupIndex);
uint parameter=0;
bool isLookupReversal = IsLookupReversal(TableTag, lookup.LookupType());
while(firstGlyph < GlyphInfo.Length) // While we have ranges to work on
{
if (!OpenTypeLayoutCache.FindNextGlyphInLookup(workspace, lookupIndex, isLookupReversal, ref firstGlyph, ref afterLastGlyph))
{
firstGlyph = afterLastGlyph;
}
if (firstGlyph < afterLastGlyph) // Apply lookup while in one range
{
int nextGlyph;
int oldLength = GlyphInfo.Length;
int glyphsAfterLastChar = oldLength - afterLastGlyph;
bool match = ApplyLookup(
Font, // In: Font access interface
TableTag, // Layout table tag (GSUB or GPOS)
Table, // Layout table (GSUB or GPOS)
Metrics, // In: LayoutMetrics
lookup, // Lookup definition structure
CharCount,
Charmap, // In: Char to glyph mapping
GlyphInfo, // In/out: List of GlyphInfo structs
Advances, // In/out: Glyph adv.widths
Offsets, // In/out: Glyph offsets
firstGlyph, // where to apply it
afterLastGlyph, // how long is a context we can use
parameter, // lookup parameter
0, // Nesting level for contextual lookups
out nextGlyph // out: next glyph index
// !!!: for reversal lookup, should
// return new afterLastGlyph
);
if (match)
{
//Adjust range end if length changed,
// for reversal changes happens beyond afterLast, no change needed
if (!isLookupReversal)
{
OpenTypeLayoutCache.OnGlyphsChanged(workspace, GlyphInfo, oldLength, firstGlyph, nextGlyph);
afterLastGlyph = GlyphInfo.Length - glyphsAfterLastChar;
firstGlyph = nextGlyph;
}
else
{
OpenTypeLayoutCache.OnGlyphsChanged(workspace, GlyphInfo, oldLength, nextGlyph, afterLastGlyph);
afterLastGlyph = nextGlyph;
}
}
else
{
if (isLookupReversal)
afterLastGlyph = nextGlyph;
else
firstGlyph = nextGlyph;
}
}
else // End of range. Get next
{
GetNextEnabledGlyphRange(
FeatureSet,
featureCount,
featureSetOffset,
Table,
workspace,
LangSys,
Features,
lookupIndex,
CharCount,
Charmap,
afterLastChar,
afterLastGlyph,
GlyphInfo.Length,
out firstChar,
out afterLastChar,
out firstGlyph,
out afterLastGlyph,
out parameter);
}
}
}
}
///
/// Critical - calls critical code (GetNextGlyphInLookup),
/// accepts pointer parameters, unsafe code
///
[SecurityCritical]
internal static bool ApplyLookup(
IOpenTypeFont Font, // Font access interface
OpenTypeTags TableTag, // Layout table tag (GSUB or GPOS)
FontTable Table, // Layout table (GSUB or GPOS)
LayoutMetrics Metrics, // LayoutMetrics
LookupTable Lookup, // List definition structure
int CharCount, // Characters count (i.e. Charmap.Length);
UshortList Charmap, // Char to glyph mapping
GlyphInfoList GlyphInfo, // List of GlyphInfo structs
int* Advances, // Glyph adv.widths
LayoutOffset* Offsets, // Glyph offsets
int FirstGlyph, // where to apply it
int AfterLastGlyph, // how long is a context we can use
uint Parameter, // lookup parameter
int nestingLevel, // Contextual lookup nesting level
out int NextGlyph // out: next glyph index
)
{
Debug.Assert(TableTag==OpenTypeTags.GSUB || TableTag==OpenTypeTags.GPOS);
Debug.Assert(FirstGlyph=AfterLastGlyph) return match;
ushort originalLookupType = lookupType; // We need it to recover, if extension lookup updated lookupFormat
for(ushort subtableIndex=0; !match && subtableIndex < subtableCount; subtableIndex++)
{
lookupType = originalLookupType;
int subtableOffset = Lookup.SubtableOffset(Table, subtableIndex);
switch (TableTag)
{
case OpenTypeTags.GSUB:
{
if (lookupType == 7)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(Table);
subtableOffset = extension.LookupSubtableOffset(Table);
}
switch (lookupType)
{
case 1: //SingleSubst
SingleSubstitutionSubtable singleSub =
new SingleSubstitutionSubtable(subtableOffset);
match = singleSub.Apply( Table,
GlyphInfo,
FirstGlyph,
out NextGlyph
);
break;
case 2: //MultipleSubst
MultipleSubstitutionSubtable multipleSub =
new MultipleSubstitutionSubtable(subtableOffset);
match = multipleSub.Apply( Font,
Table,
CharCount,
Charmap,
GlyphInfo,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 3: //AlternateSubst
AlternateSubstitutionSubtable alternateSub =
new AlternateSubstitutionSubtable(subtableOffset);
match = alternateSub.Apply( Table,
GlyphInfo,
Parameter,
FirstGlyph,
out NextGlyph
);
break;
case 4: //Ligature subst
LigatureSubstitutionSubtable ligaSub =
new LigatureSubstitutionSubtable(subtableOffset);
match = ligaSub.Apply( Font,
Table,
CharCount,
Charmap,
GlyphInfo,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 5: //ContextualSubst
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
match = contextSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 6: //ChainingSubst
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
match = chainingSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 7: //Extension lookup
// Ext.Lookup processed earlier. It can't contain another ext.lookups in it.
// Just skip it (do nothing);
NextGlyph = FirstGlyph + 1;
break;
case 8: //ReverseCahiningSubst
ReverseChainingSubtable reverseChainingSub =
new ReverseChainingSubtable(subtableOffset);
match = reverseChainingSub.Apply(
Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
out NextGlyph
);
break;
default:
// Unknown format
NextGlyph = FirstGlyph+1;
break;
}
if (match)
{
if (!IsLookupReversal(TableTag,lookupType))
{
UpdateGlyphFlags(Font,GlyphInfo,FirstGlyph,NextGlyph,true,GlyphFlags.Substituted);
}
else
{
UpdateGlyphFlags(Font,GlyphInfo,NextGlyph,AfterLastGlyph,true,GlyphFlags.Substituted);
}
}
break;
}
case OpenTypeTags.GPOS:
{
if (lookupType == 9)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(Table);
subtableOffset = extension.LookupSubtableOffset(Table);
}
switch (lookupType)
{
case 1: //SinglePos
SinglePositioningSubtable singlePos =
new SinglePositioningSubtable(subtableOffset);
match = singlePos.Apply(Table,
Metrics,
GlyphInfo,
Advances,
Offsets,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 2: //PairPos
PairPositioningSubtable pairPos =
new PairPositioningSubtable(subtableOffset);
match = pairPos.Apply( Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 3: // CursivePos
// Under construction
CursivePositioningSubtable cursivePositioningSubtable =
new CursivePositioningSubtable(subtableOffset);
cursivePositioningSubtable.Apply( Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 4: //MarkToBasePos
MarkToBasePositioningSubtable markToBasePos =
new MarkToBasePositioningSubtable(subtableOffset);
match = markToBasePos.Apply(Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 5: //MarkToLigaturePos
// Under construction
MarkToLigaturePositioningSubtable markToLigaPos =
new MarkToLigaturePositioningSubtable(subtableOffset);
match = markToLigaPos.Apply(
Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
CharCount, // Characters count (i.e. Charmap.Length);
Charmap, // Char to glyph mapping
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 6: //MarkToMarkPos
MarkToMarkPositioningSubtable markToMarkPos =
new MarkToMarkPositioningSubtable(subtableOffset);
match = markToMarkPos.Apply(
Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 7: // Contextual
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
match = contextSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 8: // Chaining
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
match = chainingSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 9: //Extension lookup
// Ext.Lookup processed earlier. It can't contain another ext.lookups in it.
// Just skip it (do nothing);
NextGlyph = FirstGlyph + 1;
break;
default:
// Unknown format
NextGlyph = FirstGlyph + 1;
break;
}
if (match)
{
UpdateGlyphFlags(Font,GlyphInfo,FirstGlyph,NextGlyph,false,GlyphFlags.Positioned);
}
break;
}
default:
Debug.Assert(false,"Unknown OpenType layout table!");
break;
}
}
return match;
}
private static bool IsLookupReversal(OpenTypeTags TableTag, ushort LookupType)
{
return (TableTag == OpenTypeTags.GSUB && LookupType == 8);
}
///
/// Critical - The method reads into raw font table bits.
///
[SecurityCritical]
private static void CompileFeatureSet(
Feature[] FeatureSet, // In: List of features to apply
int featureCount, // In: Actual number of features in FeatureSet
int featureSetOffset, //In: Offset of character input sequence inside feature set
int charCount, // In: number of characters in the input string
FontTable Table, // In: Layout table (GSUB or GPOS)
LangSysTable LangSys, // In: Language system
FeatureList Features, // In: List of Features in layout table
int lookupCount, // In: number of lookup in layout table
OpenTypeLayoutWorkspace workspace // In: workspace with compiled feature set
)
{
workspace.InitLookupUsageFlags(lookupCount, featureCount);
//Set lookup uasge flags for required feature
FeatureTable requiredFeatureTable = LangSys.RequiredFeature(Table, Features);
if (!requiredFeatureTable.IsNull)
{
int featureLookupCount = requiredFeatureTable.LookupCount(Table);
for(ushort lookup = 0; lookup < featureLookupCount; lookup++)
{
workspace.SetRequiredFeatureFlag(requiredFeatureTable.LookupIndex(Table,lookup));
}
}
//Set lookup usage flags for each feature in the FeatureSet
for(int feature = 0; feature < featureCount; feature++)
{
Feature featureDescription = FeatureSet[feature];
//Filter out features which:
// Not enabled or applied completely before or after input characters
if (featureDescription.Parameter == 0 ||
featureDescription.StartIndex >= (featureSetOffset + charCount) ||
(featureDescription.StartIndex+featureDescription.Length) <= featureSetOffset
)
{
continue;
}
FeatureTable featureTable = LangSys.FindFeature( Table,
Features,
featureDescription.Tag);
if (featureTable.IsNull)
{
continue;
}
int featureLookupCount = featureTable.LookupCount(Table);
for(ushort lookup = 0; lookup < featureLookupCount; lookup++)
{
workspace.SetFeatureFlag(featureTable.LookupIndex(Table,lookup), feature);
}
}
}
///
/// Critical - This method reads into unsafe cluster map.
///
[SecurityCritical]
private static void GetNextEnabledGlyphRange(
Feature[] FeatureSet, // In: List of features to apply
int featureCount, // In: Actual nubmer of features in FeatureSet
int featureSetOffset, // In: offset of input chars inside feature set
FontTable Table, // Layout table (GSUB or GPOS)
OpenTypeLayoutWorkspace workspace, // workspace with compiled feature set
LangSysTable LangSys, // Language system
FeatureList Features, // List of Features in layout table
ushort lookupIndex, // List of lokups definitions in layout table
int CharCount, // Characters count (i.e. Charmap.Length);
UshortList Charmap, // Character to glyph mapping
int StartChar,
int StartGlyph,
int GlyphRunLength,
out int FirstChar, // First char in enabled range
out int AfterLastChar, // next char after enabled range
out int FirstGlyph, // First char in enabled range
out int AfterLastGlyph, // next char after enabled range
out uint Parameter // applied feature parameter
)
{
FirstChar = int.MaxValue;
AfterLastChar = int.MaxValue;
FirstGlyph = StartGlyph;
AfterLastGlyph = GlyphRunLength;
Parameter = 0;
if (workspace.IsRequiredFeatureFlagSet(lookupIndex))
{
FirstChar = StartChar;
AfterLastChar = CharCount;
FirstGlyph = StartGlyph;
AfterLastGlyph = GlyphRunLength;
return;
}
for(int feature=0; feature < featureCount; feature++)
{
if (!workspace.IsFeatureFlagSet(lookupIndex,feature))
{
continue;
}
Feature featureDescription = FeatureSet[feature];
// Shift values from the feature by specified offset and
// work with these values from here
int featureStart = featureDescription.StartIndex - featureSetOffset;
if (featureStart < 0)
{
featureStart = 0;
}
int featureAfterEnd = featureDescription.StartIndex + featureDescription.Length
- featureSetOffset;
if (featureAfterEnd > CharCount)
{
featureAfterEnd = CharCount;
}
//If feature is disabled there should not be any flag set
Debug.Assert(featureDescription.Parameter != 0);
if (featureAfterEnd <= StartChar)
{
continue;
}
if (featureStart < FirstChar ||
(
featureStart == FirstChar &&
featureAfterEnd >= AfterLastChar
)
)
{
FirstChar = featureStart;
AfterLastChar = featureAfterEnd;
Parameter = featureDescription.Parameter;
continue;
}
}
//No ranges found
if (FirstChar == int.MaxValue)
{
FirstGlyph = GlyphRunLength;
AfterLastGlyph = GlyphRunLength;
}
else
{
if (StartGlyph > Charmap[FirstChar])
FirstGlyph = StartGlyph;
else
FirstGlyph = Charmap[FirstChar];
if (AfterLastChar < CharCount)
AfterLastGlyph = Charmap[AfterLastChar];
else
AfterLastGlyph = GlyphRunLength;
}
}
///
/// Critical - access protected font information (FontTable)
///
[SecurityCritical]
private static void UpdateGlyphFlags(
IOpenTypeFont Font,
GlyphInfoList GlyphInfo,
int FirstGlyph,
int AfterLastGlyph,
bool DoAll,
GlyphFlags FlagToSet
)
{
Debug.Assert( FlagToSet==GlyphFlags.NotChanged ||
FlagToSet==GlyphFlags.Substituted ||
FlagToSet==GlyphFlags.Positioned);
ushort typemask = (ushort)GlyphFlags.GlyphTypeMask;
FontTable gdefTable = Font.GetFontTable(OpenTypeTags.GDEF);
if (!gdefTable.IsPresent)
{
//GDEF(i.e. class def in it) is not present.
//Assign unassigned to all glyphs
for(int i=FirstGlyph;i
/// Critical - Access protected font information (FontTable).
///
[SecurityCritical]
internal static int GetNextGlyphInLookup(
IOpenTypeFont Font, //
GlyphInfoList GlyphInfo, // Glyph run
int FirstGlyph, // Current glyph index
ushort LookupFlags, // Lookup flags to use
int Direction // Search direction (forward/back)
)
{
FontTable gdefTable;
ClassDefTable markAttachClassDef;
//assign them only to avoid error: using unassigned variable
gdefTable = null;
markAttachClassDef = ClassDefTable.InvalidClassDef;
if (LookupFlags==0) return FirstGlyph;
//we will mark classes only if mark filter is set
if ((LookupFlags&(ushort)LookupFlagMarkAttachmentTypeMask)!=0)
{
gdefTable = Font.GetFontTable(OpenTypeTags.GDEF);
if (gdefTable.IsPresent)
{
markAttachClassDef = (new GDEFHeader(0)).GetMarkAttachClassDef(gdefTable);
}
}
UshortList glyphFlags = GlyphInfo.GlyphFlags;
ushort attachClass = (ushort)((LookupFlags&LookupFlagMarkAttachmentTypeMask)>>8);
int glyph;
int glyphRunLength = GlyphInfo.Length;
for(glyph=FirstGlyph; glyph=0; glyph+=Direction)
{
if (
(LookupFlags&LookupFlagIgnoreBases)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Base
) continue;
if (
(LookupFlags&LookupFlagIgnoreMarks)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Mark
) continue;
if (
(LookupFlags&LookupFlagIgnoreLigatures)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Ligature
) continue;
if (attachClass!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Mark &&
!markAttachClassDef.IsInvalid &&
attachClass!=markAttachClassDef.GetClass(gdefTable,GlyphInfo.Glyphs[glyph])
) continue;
return glyph;
}
return glyph;
}
///
/// Returns list of the languages, that can not be optimized for simple shaping
///
///
/// Critical - The method reads into raw font table bits
///
[SecurityCritical]
internal static void GetComplexLanguageList(
OpenTypeTags tableTag,
FontTable table,
uint[] featureTagsList,
uint[] glyphBits,
ushort minGlyphId,
ushort maxGlyphId,
out WritingSystem[] complexLanguages,
out int complexLanguageCount
)
{
ScriptList scriptList = new ScriptList(0);
FeatureList featureList = new FeatureList(0);
LookupList lookupList = new LookupList(0);
Debug.Assert(tableTag == OpenTypeTags.GSUB || tableTag == OpenTypeTags.GPOS);
switch (tableTag)
{
case OpenTypeTags.GSUB:
GSUBHeader gsubHeader = new GSUBHeader(0);
scriptList = gsubHeader.GetScriptList(table);
featureList = gsubHeader.GetFeatureList(table);
lookupList = gsubHeader.GetLookupList(table);
break;
case OpenTypeTags.GPOS:
GPOSHeader gposHeader = new GPOSHeader(0);
scriptList = gposHeader.GetScriptList(table);
featureList = gposHeader.GetFeatureList(table);
lookupList = gposHeader.GetLookupList(table);
break;
}
int scriptCount = scriptList.GetScriptCount(table);
int featureCount = featureList.FeatureCount(table);
int lookupCount = lookupList.LookupCount(table);
// We will mark lookups that should be tested.
// At the end, we will have only complex ones marked
uint[] lookupBits = new uint[(lookupCount+31)>>5];
for(int i = 0; i < (lookupCount+31)>>5; i++)
{
lookupBits[i] = 0;
}
// Iterate through list of featuers in the table
for(ushort featureIndex = 0; featureIndex < featureCount; featureIndex++)
{
uint featureTag = (uint)featureList.FeatureTag(table, featureIndex);
bool tagFound = false;
//Search for tag in the list of features in question
for(int j = 0; j < featureTagsList.Length; j++)
{
if (featureTagsList[j] == featureTag)
{
tagFound = true;
break;
}
}
if (tagFound)
{
// We should mark all lookup mapped to this feature
FeatureTable featureTable = featureList.FeatureTable(table, featureIndex);
ushort featureLookupCount = featureTable.LookupCount(table);
for(ushort j = 0; j < featureLookupCount; j++)
{
ushort lookupIndex = featureTable.LookupIndex(table, j);
if (lookupIndex >= lookupCount)
{
//This should be invalid font. Lookup associated with the feature is not in lookup array.
throw new FileFormatException();
}
lookupBits[lookupIndex>>5] |= (uint)(1 << (lookupIndex%32));
}
}
}
//
//
//Now test all marked lookups
for(ushort lookupIndex = 0; lookupIndex < lookupCount; lookupIndex++)
{
if ((lookupBits[lookupIndex>>5] & (1 << (lookupIndex%32))) == 0)
{
continue;
}
LookupTable lookup = lookupList.Lookup(table,lookupIndex);
ushort lookupType = lookup.LookupType();
ushort subtableCount = lookup.SubTableCount();
bool lookupIsCovered = false;
ushort originalLookupType = lookupType; // We need it to recover,
// if extension lookup updated lookupFormat
for(ushort subtableIndex = 0;
!lookupIsCovered && subtableIndex < subtableCount;
subtableIndex++)
{
lookupType = originalLookupType;
int subtableOffset = lookup.SubtableOffset(table, subtableIndex);
switch (tableTag)
{
case OpenTypeTags.GSUB:
{
if (lookupType == 7)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(table);
subtableOffset = extension.LookupSubtableOffset(table);
}
switch (lookupType)
{
case 1: //SingleSubst
SingleSubstitutionSubtable singleSub =
new SingleSubstitutionSubtable(subtableOffset);
lookupIsCovered = singleSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 2: //MultipleSubst
MultipleSubstitutionSubtable multipleSub =
new MultipleSubstitutionSubtable(subtableOffset);
lookupIsCovered = multipleSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 3: //AlternateSubst
AlternateSubstitutionSubtable alternateSub =
new AlternateSubstitutionSubtable(subtableOffset);
lookupIsCovered = alternateSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 4: //Ligature subst
LigatureSubstitutionSubtable ligaSub =
new LigatureSubstitutionSubtable(subtableOffset);
lookupIsCovered = ligaSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 5: //ContextualSubst
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
lookupIsCovered = contextSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 6: //ChainingSubst
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
lookupIsCovered = chainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 7: //Extension lookup
Debug.Assert(false,"Ext.Lookup processed earlier!");
break;
case 8: //ReverseCahiningSubst
ReverseChainingSubtable reverseChainingSub =
new ReverseChainingSubtable(subtableOffset);
lookupIsCovered = reverseChainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
default:
// Unknown format
lookupIsCovered = true;
break;
}
break;
}
case OpenTypeTags.GPOS:
{
if (lookupType == 9)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(table);
subtableOffset = extension.LookupSubtableOffset(table);
}
switch (lookupType)
{
case 1: //SinglePos
SinglePositioningSubtable singlePos =
new SinglePositioningSubtable(subtableOffset);
lookupIsCovered = singlePos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 2: //PairPos
PairPositioningSubtable pairPos =
new PairPositioningSubtable(subtableOffset);
lookupIsCovered = pairPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 3: // CursivePos
// Under construction
CursivePositioningSubtable cursivePositioningSubtable =
new CursivePositioningSubtable(subtableOffset);
lookupIsCovered = cursivePositioningSubtable.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 4: //MarkToBasePos
MarkToBasePositioningSubtable markToBasePos =
new MarkToBasePositioningSubtable(subtableOffset);
lookupIsCovered = markToBasePos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 5: //MarkToLigaturePos
// Under construction
MarkToLigaturePositioningSubtable markToLigaPos =
new MarkToLigaturePositioningSubtable(subtableOffset);
lookupIsCovered = markToLigaPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 6: //MarkToMarkPos
MarkToMarkPositioningSubtable markToMarkPos =
new MarkToMarkPositioningSubtable(subtableOffset);
lookupIsCovered = markToMarkPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 7: // Contextual
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
lookupIsCovered = contextSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 8: // Chaining
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
lookupIsCovered = chainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 9: //Extension lookup
Debug.Assert(false,"Ext.Lookup processed earlier!");
break;
default:
// Unknown format
lookupIsCovered = true;
break;
}
break;
}
default:
Debug.Assert(false,"Unknown OpenType layout table!");
break;
}
}
if (!lookupIsCovered)
{
// Clean the flag
lookupBits[lookupIndex>>5] &= ~(uint)(1 << (lookupIndex%32));
}
}
// Check if we have any lookup left
bool complexLookupFound = false;
for(int i = 0; i < (lookupCount+31)>>5; i++)
{
if (lookupBits[i] != 0)
{
complexLookupFound = true;
break;
}
}
if (!complexLookupFound)
{
// There are no complex lookups
complexLanguages = null;
complexLanguageCount = 0;
return;
}
// Now go through all langauages and fill the list
complexLanguages = new WritingSystem[10];
complexLanguageCount = 0;
for(ushort scriptIndex = 0; scriptIndex < scriptCount; scriptIndex++)
{
ScriptTable scriptTable = scriptList.GetScriptTable(table, scriptIndex);
uint scriptTag = scriptList.GetScriptTag(table, scriptIndex);
ushort langSysCount = scriptTable.GetLangSysCount(table);
if (scriptTable.IsDefaultLangSysExists(table))
{
AppendLangSys(scriptTag, (uint)OpenTypeTags.dflt,
scriptTable.GetDefaultLangSysTable(table),
featureList,
table,
featureTagsList,
lookupBits,
ref complexLanguages,
ref complexLanguageCount
);
}
for(ushort langSysIndex = 0; langSysIndex < langSysCount; langSysIndex++)
{
uint langSysTag = scriptTable.GetLangSysTag(table, langSysIndex);
AppendLangSys(scriptTag, langSysTag,
scriptTable.GetLangSysTable(table, langSysIndex),
featureList,
table,
featureTagsList,
lookupBits,
ref complexLanguages,
ref complexLanguageCount
);
}
}
}
///
/// Critical - The method reads into raw font table bits.
///
[SecurityCritical]
private static void AppendLangSys(
uint scriptTag,
uint langSysTag,
LangSysTable langSysTable,
FeatureList featureList,
FontTable table,
uint[] featureTagsList,
uint[] lookupBits,
ref WritingSystem[] complexLanguages,
ref int complexLanguageCount
)
{
ushort featureCount = langSysTable.FeatureCount(table);
bool complexFeatureFound = false;
//
for(ushort i = 0; !complexFeatureFound && i < featureCount; i++)
{
ushort featureIndex = langSysTable.GetFeatureIndex(table, i);
uint featureTag = featureList.FeatureTag(table,featureIndex);
bool tagFound = false;
for(int j = 0; !complexFeatureFound && j < featureTagsList.Length; j++)
{
if (featureTagsList[j] == featureTag)
{
tagFound = true;
break;
}
}
if (tagFound)
{
// We should check if any of lookups is complex
FeatureTable featureTable = featureList.FeatureTable(table, featureIndex);
ushort featureLookupCount = featureTable.LookupCount(table);
for(ushort j = 0; j < featureLookupCount; j++)
{
ushort lookupIndex = featureTable.LookupIndex(table, j);
if ((lookupBits[lookupIndex>>5] & (1 << (lookupIndex%32))) != 0)
{
complexFeatureFound = true;
break;
}
}
}
}
if (complexFeatureFound)
{
if (complexLanguages.Length == complexLanguageCount)
{
WritingSystem[] newComplexLanguages =
new WritingSystem[complexLanguages.Length * 3 /2];
for(int i = 0; i < complexLanguages.Length; i++)
{
newComplexLanguages[i] = complexLanguages[i];
}
complexLanguages = newComplexLanguages;
}
complexLanguages[complexLanguageCount].scriptTag = scriptTag;
complexLanguages[complexLanguageCount].langSysTag = langSysTag;
complexLanguageCount++;
}
}
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GSUBHeader
{
private const int offsetScriptList = 4;
private const int offsetFeatureList = 6;
private const int offsetLookupList = 8;
public ScriptList GetScriptList(FontTable Table)
{
return new ScriptList(offset+Table.GetOffset(offset+offsetScriptList));
}
public FeatureList GetFeatureList(FontTable Table)
{
return new FeatureList(offset+Table.GetOffset(offset+offsetFeatureList));
}
public LookupList GetLookupList(FontTable Table)
{
return new LookupList(offset+Table.GetOffset(offset+offsetLookupList));
}
public GSUBHeader(int Offset)
{
offset = Offset;
}
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GPOSHeader
{
private const int offsetScriptList = 4;
private const int offsetFeatureList = 6;
private const int offsetLookupList = 8;
public ScriptList GetScriptList(FontTable Table)
{
return new ScriptList(offset+Table.GetOffset(offset+offsetScriptList));
}
public FeatureList GetFeatureList(FontTable Table)
{
return new FeatureList(offset+Table.GetOffset(offset+offsetFeatureList));
}
public LookupList GetLookupList(FontTable Table)
{
return new LookupList(offset+Table.GetOffset(offset+offsetLookupList));
}
public GPOSHeader(int Offset)
{
offset = Offset;
}
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GDEFHeader
{
private const int offsetGlyphClassDef = 4;
private const int offsetGlyphAttachList = 6;
private const int offsetLigaCaretList = 8;
private const int offsetMarkAttachClassDef = 10;
public ClassDefTable GetGlyphClassDef(FontTable Table)
{
//There is only one place where GDEF classdef is retireved -
// UpdateGlyphFlags. We will check if GDEF is present there
Invariant.Assert(Table.IsPresent);
return new ClassDefTable(offset + Table.GetOffset(offset + offsetGlyphClassDef));
}
// ///
// /// Under construction
// /// Glyph attachment points list
// ///
// ///
// ///
// /// Under construction
// /// Ligature caret positioning data
// ///
// ///
// ///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ScriptList
{
private const int offsetScriptCount = 0;
private const int offsetScriptRecordArray = 2;
private const int sizeScriptRecord = 6;
private const int offsetScriptRecordTag = 0;
private const int offsetScriptRecordOffset = 4;
public ScriptTable FindScript(FontTable Table, uint Tag)
{
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ScriptTable
{
private const int offsetDefaultLangSys = 0;
private const int offsetLangSysCount = 2;
private const int offsetLangSysRecordArray = 4;
private const int sizeLangSysRecord = 6;
private const int offsetLangSysRecordTag = 0;
private const int offsetLangSysRecordOffset = 4;
public LangSysTable FindLangSys(FontTable Table, uint Tag)
{
if (IsNull)
{
return new LangSysTable(FontTable.InvalidOffset);
}
if ((OpenTypeTags)Tag==OpenTypeTags.dflt)
{
if (IsDefaultLangSysExists(Table))
return new LangSysTable(offset +
Table.GetOffset(offset + offsetDefaultLangSys));
return new LangSysTable(FontTable.InvalidOffset);
}
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LangSysTable
{
private const int offsetRequiredFeature = 2;
private const int offsetFeatureCount = 4;
private const int offsetFeatureIndexArray = 6;
private const int sizeFeatureIndex = 2;
public FeatureTable FindFeature(FontTable Table, FeatureList Features, uint FeatureTag)
{
ushort featureCount = FeatureCount(Table);
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct FeatureList
{
private const int offsetFeatureCount = 0;
private const int offsetFeatureRecordArray = 2;
private const int sizeFeatureRecord = 6;
private const int offsetFeatureRecordTag = 0;
private const int offsetFeatureRecordOffset = 4;
public ushort FeatureCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFeatureCount);
}
public uint FeatureTag(FontTable Table,ushort Index)
{
return Table.GetUInt(offset + offsetFeatureRecordArray +
Index * sizeFeatureRecord +
offsetFeatureRecordTag);
}
public FeatureTable FeatureTable(FontTable Table,ushort Index)
{
return new FeatureTable(offset+Table.GetUShort(offset +
offsetFeatureRecordArray +
Index * sizeFeatureRecord +
offsetFeatureRecordOffset));
}
public FeatureList(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct FeatureTable
{
private const int offsetLookupCount = 2;
private const int offsetLookupIndexArray = 4;
private const int sizeLookupIndex = 2;
public ushort LookupCount(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupCount);
}
public ushort LookupIndex(FontTable Table,ushort Index)
{
return Table.GetUShort(offset + offsetLookupIndexArray + Index*sizeLookupIndex);
}
public FeatureTable(int Offset){ offset = Offset; }
public bool IsNull { get{ return (offset==FontTable.InvalidOffset); } }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LookupList
{
private const int offsetLookupCount = 0;
private const int LookupOffsetArray = 2;
private const int sizeLookupOffset = 2;
public ushort LookupCount(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupCount);
}
public LookupTable Lookup(FontTable Table, ushort Index)
{
return new LookupTable(Table, offset + Table.GetUShort(offset + LookupOffsetArray +
Index * sizeLookupOffset));
}
public LookupList(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LookupTable
{
private const int offsetLookupType = 0;
private const int offsetLookupFlags = 2;
private const int offsetSubtableCount = 4;
private const int offsetSubtableArray = 6;
private const int sizeSubtableOffset = 2;
public ushort LookupType()
{
return lookupType;
}
public ushort LookupFlags()
{
return lookupFlags;
}
public ushort SubTableCount()
{
return subtableCount;
}
public int SubtableOffset(FontTable Table, ushort Index)
{
Debug.Assert(Index < SubTableCount());
return offset+Table.GetOffset(offset + offsetSubtableArray +
Index*sizeSubtableOffset);
}
public LookupTable(FontTable table, int Offset)
{
offset = Offset;
lookupType = table.GetUShort(offset + offsetLookupType);
lookupFlags = table.GetUShort(offset + offsetLookupFlags);
subtableCount = table.GetUShort(offset + offsetSubtableCount);
}
private int offset;
private ushort lookupType;
private ushort lookupFlags;
private ushort subtableCount;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct CoverageTable
{
private const int offsetFormat = 0;
private const int offsetFormat1GlyphCount = 2;
private const int offsetFormat1GlyphArray = 4;
private const int sizeFormat1GlyphId = 2;
private const int offsetFormat2RangeCount = 2;
private const int offsetFormat2RangeRecordArray = 4;
private const int sizeFormat2RangeRecord = 6;
private const int offsetFormat2RangeRecordStart = 0;
private const int offsetFormat2RangeRecordEnd = 2;
private const int offsetFormat2RangeRecordStartIndex = 4;
public ushort Format(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat);
}
public ushort Format1GlyphCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1GlyphCount);
}
public ushort Format1Glyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat1GlyphArray +
Index*sizeFormat1GlyphId);
}
public ushort Format2RangeCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat2RangeCount);
}
public ushort Format2RangeStartGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStart);
}
public ushort Format2RangeEndGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordEnd);
}
public ushort Format2RangeStartCoverageIndex(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStartIndex);
}
public int GetGlyphIndex(FontTable Table, ushort glyph)
{
switch (Format(Table))
{
case 1: // Coverage array
{
ushort lowIndex = 0;
ushort highIndex = Format1GlyphCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
ushort middleGlyph = Format1Glyph(Table,middleIndex);
if (glyph < middleGlyph)
{
highIndex = middleIndex;
}
else if (glyph > middleGlyph)
{
lowIndex = (ushort)(middleIndex+1);
}
else
{
return middleIndex;
}
}
return -1;
}
case 2: //Glyph Ranges
{
ushort lowIndex = 0;
ushort highIndex = Format2RangeCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
if (glyph < Format2RangeStartGlyph(Table, middleIndex))
{
highIndex = middleIndex;
}
else if (glyph > Format2RangeEndGlyph(Table, middleIndex))
{
lowIndex = (ushort)(middleIndex + 1);
}
else
{
return (glyph - Format2RangeStartGlyph(Table,middleIndex))
+ Format2RangeStartCoverageIndex(Table,middleIndex);
}
}
return -1;
}
default:
//unknown format. Return NoMatch.
return -1;
}
}
public bool IsAnyGlyphCovered(
FontTable table,
uint[] glyphBits,
ushort minGlyphId,
ushort maxGlyphId)
{
switch (Format(table))
{
case 1: // Coverage array
{
ushort glyphCount = Format1GlyphCount(table);
if (glyphCount == 0) return false;
ushort firstGlyphId = Format1Glyph(table, 0);
ushort lastGlyphId = Format1Glyph(table, (ushort)(glyphCount - 1));
if (maxGlyphId < firstGlyphId || minGlyphId > lastGlyphId) return false;
for(ushort i = 0; i < glyphCount; i++)
{
ushort glyphId = Format1Glyph(table, i);
if (glyphId <= maxGlyphId &&
glyphId >= minGlyphId &&
(glyphBits[glyphId >> 5] & (1 << (glyphId % 32))) != 0
)
{
return true;
}
}
return false;
}
case 2: //Glyph Ranges
{
ushort rangeCount = Format2RangeCount(table);
if (rangeCount == 0) return false;
ushort firstGlyphId = Format2RangeStartGlyph(table,0);
ushort lastGlyphId = Format2RangeEndGlyph(table, (ushort)(rangeCount - 1));
if (maxGlyphId < firstGlyphId || minGlyphId > lastGlyphId) return false;
for (ushort rangeIndex = 0; rangeIndex < rangeCount; rangeIndex++)
{
ushort startGlyphId = Format2RangeStartGlyph(table,rangeIndex);
ushort endGlyphId = Format2RangeEndGlyph(table, rangeIndex);
for (ushort glyphId = startGlyphId; glyphId <= endGlyphId; glyphId++)
{
if (glyphId <= maxGlyphId &&
glyphId >= minGlyphId &&
(glyphBits[glyphId >> 5] & (1 << (glyphId % 32))) != 0
)
{
return true;
}
}
}
return false;
}
default:
//unknown format. Return true.
return true;
}
}
public static CoverageTable InvalidCoverage
{
get { return new CoverageTable(-1); }
}
public bool IsInvalid
{
get { return offset == -1; }
}
public CoverageTable(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ClassDefTable
{
private const int offsetFormat = 0;
private const int offsetFormat1StartGlyph = 2;
private const int offsetFormat1GlyphCount = 4;
private const int offsetFormat1ClassValueArray = 6;
private const int sizeFormat1ClassValue = 2;
private const int offsetFormat2RangeCount = 2;
private const int offsetFormat2RangeRecordArray = 4;
private const int sizeFormat2RangeRecord = 6;
private const int offsetFormat2RangeRecordStart = 0;
private const int offsetFormat2RangeRecordEnd = 2;
private const int offsetFormat2RangeRecordClass = 4;
private ushort Format(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat);
}
private ushort Format1StartGlyph(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1StartGlyph);
}
private ushort Format1GlyphCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1GlyphCount);
}
private ushort Format1ClassValue(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat1ClassValueArray +
Index*sizeFormat1ClassValue);
}
private ushort Format2RangeCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat2RangeCount);
}
private ushort Format2RangeStartGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStart);
}
private ushort Format2RangeEndGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordEnd);
}
private ushort Format2RangeClassValue(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordClass);
}
public ushort GetClass(FontTable Table, ushort glyph)
{
//PERF: binary search!!!
switch (Format(Table))
{
case 1: // ClassDef array
{
ushort startGlyph = Format1StartGlyph(Table);
ushort glyphCount = Format1GlyphCount(Table);
if (glyph >= startGlyph && (glyph - startGlyph) < glyphCount)
return Format1ClassValue(Table,(ushort)(glyph - startGlyph));
else
return 0;
}
case 2: //ClassDef Ranges
{
ushort lowIndex = 0;
ushort highIndex = Format2RangeCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
if (glyph < Format2RangeStartGlyph(Table, middleIndex))
{
highIndex = middleIndex;
}
else if (glyph > Format2RangeEndGlyph(Table, middleIndex))
{
lowIndex = (ushort)(middleIndex + 1);
}
else
{
return Format2RangeClassValue(Table,middleIndex);
}
}
return 0;
}
default:
//unknown format. Return default: 0
return 0;
}
}
public static ClassDefTable InvalidClassDef
{
get { return new ClassDefTable(-1); }
}
public bool IsInvalid
{
get { return offset == -1; }
}
public ClassDefTable(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ExtensionLookupTable
{
private const int offsetFormat = 0;
private const int offsetLookupType = 2;
private const int offsetExtensionOffset = 4;
internal ushort LookupType(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupType);
}
internal int LookupSubtableOffset(FontTable Table)
{
return offset + (int)Table.GetUInt(offset + offsetExtensionOffset);
}
public ExtensionLookupTable(int Offset) { offset = Offset; }
private int offset;
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
//+------------------------------------------------------------------------
//
// Microsoft Windows Client Platform
// Copyright (C) Microsoft Corporation, 2002
//
// File: Common.cs
//
// Contents: OpentTypeLayout higher level internal engine and structures
//
// contact: sergeym
//
// History: 2002-03-23 Created (sergeym)
//
//-----------------------------------------------------------------------
using System.Diagnostics;
using System.Security;
using System.Security.Permissions;
using System;
using System.IO;
using MS.Internal;
namespace MS.Internal.Shaping
{
///
/// Provide core layout functionality
///
internal static unsafe class LayoutEngine
{
///
/// Main layout loop. Execute lookups in right order for enabled ranges
///
/// In: Font access interface
/// In: Layout engine wokrspace
/// In: Layout table tag (GSUB or GPOS)
/// In: Layout Table (GSUB or GPOS)
/// In: Layout metrics
/// In: Language system table
/// In: FeatureList
/// In: Lookup list
/// In: List of feature to apply
/// In: Actual number of features in
/// Critical - calls critical code, accepts pointer parameters, unsafe code
///
[SecurityCritical]
public static void ApplyFeatures(
IOpenTypeFont Font,
OpenTypeLayoutWorkspace workspace,
OpenTypeTags TableTag,
FontTable Table,
LayoutMetrics Metrics,
LangSysTable LangSys,
FeatureList Features,
LookupList Lookups,
Feature[] FeatureSet,
int featureCount,
int featureSetOffset,
int CharCount,
UshortList Charmap,
GlyphInfoList GlyphInfo,
int* Advances,
LayoutOffset* Offsets
)
{
UpdateGlyphFlags(Font, GlyphInfo, 0, GlyphInfo.Length, false, GlyphFlags.NotChanged);
// if client did not supply us with workspace
// we will create our own (temporarily)
if (workspace == null)
{
workspace = new OpenTypeLayoutWorkspace();
}
ushort lookupCount=Lookups.LookupCount(Table);
//Compile feature set
CompileFeatureSet(
FeatureSet,
featureCount,
featureSetOffset,
CharCount,
Table,
LangSys,
Features,
lookupCount,
workspace
);
OpenTypeLayoutCache.InitCache(Font, TableTag, GlyphInfo, workspace);
for(ushort lookupIndex = 0; lookupIndex < lookupCount; lookupIndex++)
{
if (!workspace.IsAggregatedFlagSet(lookupIndex))
{
continue;
}
int firstChar=0,
afterLastChar=0,
firstGlyph=0,
afterLastGlyph=0;
OpenTypeLayoutCache.FindNextLookup(workspace,
GlyphInfo,
lookupIndex,
out lookupIndex,
out firstGlyph);
// We need to check this again, because FindNextLookup will change lookupIndex
if (lookupIndex >= lookupCount)
{
break;
}
if (!workspace.IsAggregatedFlagSet(lookupIndex))
{
continue;
}
LookupTable lookup = Lookups.Lookup(Table, lookupIndex);
uint parameter=0;
bool isLookupReversal = IsLookupReversal(TableTag, lookup.LookupType());
while(firstGlyph < GlyphInfo.Length) // While we have ranges to work on
{
if (!OpenTypeLayoutCache.FindNextGlyphInLookup(workspace, lookupIndex, isLookupReversal, ref firstGlyph, ref afterLastGlyph))
{
firstGlyph = afterLastGlyph;
}
if (firstGlyph < afterLastGlyph) // Apply lookup while in one range
{
int nextGlyph;
int oldLength = GlyphInfo.Length;
int glyphsAfterLastChar = oldLength - afterLastGlyph;
bool match = ApplyLookup(
Font, // In: Font access interface
TableTag, // Layout table tag (GSUB or GPOS)
Table, // Layout table (GSUB or GPOS)
Metrics, // In: LayoutMetrics
lookup, // Lookup definition structure
CharCount,
Charmap, // In: Char to glyph mapping
GlyphInfo, // In/out: List of GlyphInfo structs
Advances, // In/out: Glyph adv.widths
Offsets, // In/out: Glyph offsets
firstGlyph, // where to apply it
afterLastGlyph, // how long is a context we can use
parameter, // lookup parameter
0, // Nesting level for contextual lookups
out nextGlyph // out: next glyph index
// !!!: for reversal lookup, should
// return new afterLastGlyph
);
if (match)
{
//Adjust range end if length changed,
// for reversal changes happens beyond afterLast, no change needed
if (!isLookupReversal)
{
OpenTypeLayoutCache.OnGlyphsChanged(workspace, GlyphInfo, oldLength, firstGlyph, nextGlyph);
afterLastGlyph = GlyphInfo.Length - glyphsAfterLastChar;
firstGlyph = nextGlyph;
}
else
{
OpenTypeLayoutCache.OnGlyphsChanged(workspace, GlyphInfo, oldLength, nextGlyph, afterLastGlyph);
afterLastGlyph = nextGlyph;
}
}
else
{
if (isLookupReversal)
afterLastGlyph = nextGlyph;
else
firstGlyph = nextGlyph;
}
}
else // End of range. Get next
{
GetNextEnabledGlyphRange(
FeatureSet,
featureCount,
featureSetOffset,
Table,
workspace,
LangSys,
Features,
lookupIndex,
CharCount,
Charmap,
afterLastChar,
afterLastGlyph,
GlyphInfo.Length,
out firstChar,
out afterLastChar,
out firstGlyph,
out afterLastGlyph,
out parameter);
}
}
}
}
///
/// Critical - calls critical code (GetNextGlyphInLookup),
/// accepts pointer parameters, unsafe code
///
[SecurityCritical]
internal static bool ApplyLookup(
IOpenTypeFont Font, // Font access interface
OpenTypeTags TableTag, // Layout table tag (GSUB or GPOS)
FontTable Table, // Layout table (GSUB or GPOS)
LayoutMetrics Metrics, // LayoutMetrics
LookupTable Lookup, // List definition structure
int CharCount, // Characters count (i.e. Charmap.Length);
UshortList Charmap, // Char to glyph mapping
GlyphInfoList GlyphInfo, // List of GlyphInfo structs
int* Advances, // Glyph adv.widths
LayoutOffset* Offsets, // Glyph offsets
int FirstGlyph, // where to apply it
int AfterLastGlyph, // how long is a context we can use
uint Parameter, // lookup parameter
int nestingLevel, // Contextual lookup nesting level
out int NextGlyph // out: next glyph index
)
{
Debug.Assert(TableTag==OpenTypeTags.GSUB || TableTag==OpenTypeTags.GPOS);
Debug.Assert(FirstGlyph=AfterLastGlyph) return match;
ushort originalLookupType = lookupType; // We need it to recover, if extension lookup updated lookupFormat
for(ushort subtableIndex=0; !match && subtableIndex < subtableCount; subtableIndex++)
{
lookupType = originalLookupType;
int subtableOffset = Lookup.SubtableOffset(Table, subtableIndex);
switch (TableTag)
{
case OpenTypeTags.GSUB:
{
if (lookupType == 7)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(Table);
subtableOffset = extension.LookupSubtableOffset(Table);
}
switch (lookupType)
{
case 1: //SingleSubst
SingleSubstitutionSubtable singleSub =
new SingleSubstitutionSubtable(subtableOffset);
match = singleSub.Apply( Table,
GlyphInfo,
FirstGlyph,
out NextGlyph
);
break;
case 2: //MultipleSubst
MultipleSubstitutionSubtable multipleSub =
new MultipleSubstitutionSubtable(subtableOffset);
match = multipleSub.Apply( Font,
Table,
CharCount,
Charmap,
GlyphInfo,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 3: //AlternateSubst
AlternateSubstitutionSubtable alternateSub =
new AlternateSubstitutionSubtable(subtableOffset);
match = alternateSub.Apply( Table,
GlyphInfo,
Parameter,
FirstGlyph,
out NextGlyph
);
break;
case 4: //Ligature subst
LigatureSubstitutionSubtable ligaSub =
new LigatureSubstitutionSubtable(subtableOffset);
match = ligaSub.Apply( Font,
Table,
CharCount,
Charmap,
GlyphInfo,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 5: //ContextualSubst
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
match = contextSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 6: //ChainingSubst
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
match = chainingSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 7: //Extension lookup
// Ext.Lookup processed earlier. It can't contain another ext.lookups in it.
// Just skip it (do nothing);
NextGlyph = FirstGlyph + 1;
break;
case 8: //ReverseCahiningSubst
ReverseChainingSubtable reverseChainingSub =
new ReverseChainingSubtable(subtableOffset);
match = reverseChainingSub.Apply(
Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
out NextGlyph
);
break;
default:
// Unknown format
NextGlyph = FirstGlyph+1;
break;
}
if (match)
{
if (!IsLookupReversal(TableTag,lookupType))
{
UpdateGlyphFlags(Font,GlyphInfo,FirstGlyph,NextGlyph,true,GlyphFlags.Substituted);
}
else
{
UpdateGlyphFlags(Font,GlyphInfo,NextGlyph,AfterLastGlyph,true,GlyphFlags.Substituted);
}
}
break;
}
case OpenTypeTags.GPOS:
{
if (lookupType == 9)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(Table);
subtableOffset = extension.LookupSubtableOffset(Table);
}
switch (lookupType)
{
case 1: //SinglePos
SinglePositioningSubtable singlePos =
new SinglePositioningSubtable(subtableOffset);
match = singlePos.Apply(Table,
Metrics,
GlyphInfo,
Advances,
Offsets,
FirstGlyph,
AfterLastGlyph,
out NextGlyph
);
break;
case 2: //PairPos
PairPositioningSubtable pairPos =
new PairPositioningSubtable(subtableOffset);
match = pairPos.Apply( Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 3: // CursivePos
// Under construction
CursivePositioningSubtable cursivePositioningSubtable =
new CursivePositioningSubtable(subtableOffset);
cursivePositioningSubtable.Apply( Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 4: //MarkToBasePos
MarkToBasePositioningSubtable markToBasePos =
new MarkToBasePositioningSubtable(subtableOffset);
match = markToBasePos.Apply(Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 5: //MarkToLigaturePos
// Under construction
MarkToLigaturePositioningSubtable markToLigaPos =
new MarkToLigaturePositioningSubtable(subtableOffset);
match = markToLigaPos.Apply(
Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
CharCount, // Characters count (i.e. Charmap.Length);
Charmap, // Char to glyph mapping
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 6: //MarkToMarkPos
MarkToMarkPositioningSubtable markToMarkPos =
new MarkToMarkPositioningSubtable(subtableOffset);
match = markToMarkPos.Apply(
Font,
Table,
Metrics, // LayoutMetrics
GlyphInfo, // List of GlyphInfo structs
lookupFlags, // Lookup flags for glyph lookups
Advances, // Glyph adv.widths
Offsets, // Glyph offsets
FirstGlyph, // where to apply lookup
AfterLastGlyph, // how long is a context we can use
out NextGlyph // Next glyph to process
);
break;
case 7: // Contextual
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
match = contextSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 8: // Chaining
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
match = chainingSub.Apply( Font,
TableTag,
Table,
Metrics,
CharCount,
Charmap,
GlyphInfo,
Advances,
Offsets,
lookupFlags,
FirstGlyph,
AfterLastGlyph,
Parameter,
nestingLevel,
out NextGlyph
);
break;
case 9: //Extension lookup
// Ext.Lookup processed earlier. It can't contain another ext.lookups in it.
// Just skip it (do nothing);
NextGlyph = FirstGlyph + 1;
break;
default:
// Unknown format
NextGlyph = FirstGlyph + 1;
break;
}
if (match)
{
UpdateGlyphFlags(Font,GlyphInfo,FirstGlyph,NextGlyph,false,GlyphFlags.Positioned);
}
break;
}
default:
Debug.Assert(false,"Unknown OpenType layout table!");
break;
}
}
return match;
}
private static bool IsLookupReversal(OpenTypeTags TableTag, ushort LookupType)
{
return (TableTag == OpenTypeTags.GSUB && LookupType == 8);
}
///
/// Critical - The method reads into raw font table bits.
///
[SecurityCritical]
private static void CompileFeatureSet(
Feature[] FeatureSet, // In: List of features to apply
int featureCount, // In: Actual number of features in FeatureSet
int featureSetOffset, //In: Offset of character input sequence inside feature set
int charCount, // In: number of characters in the input string
FontTable Table, // In: Layout table (GSUB or GPOS)
LangSysTable LangSys, // In: Language system
FeatureList Features, // In: List of Features in layout table
int lookupCount, // In: number of lookup in layout table
OpenTypeLayoutWorkspace workspace // In: workspace with compiled feature set
)
{
workspace.InitLookupUsageFlags(lookupCount, featureCount);
//Set lookup uasge flags for required feature
FeatureTable requiredFeatureTable = LangSys.RequiredFeature(Table, Features);
if (!requiredFeatureTable.IsNull)
{
int featureLookupCount = requiredFeatureTable.LookupCount(Table);
for(ushort lookup = 0; lookup < featureLookupCount; lookup++)
{
workspace.SetRequiredFeatureFlag(requiredFeatureTable.LookupIndex(Table,lookup));
}
}
//Set lookup usage flags for each feature in the FeatureSet
for(int feature = 0; feature < featureCount; feature++)
{
Feature featureDescription = FeatureSet[feature];
//Filter out features which:
// Not enabled or applied completely before or after input characters
if (featureDescription.Parameter == 0 ||
featureDescription.StartIndex >= (featureSetOffset + charCount) ||
(featureDescription.StartIndex+featureDescription.Length) <= featureSetOffset
)
{
continue;
}
FeatureTable featureTable = LangSys.FindFeature( Table,
Features,
featureDescription.Tag);
if (featureTable.IsNull)
{
continue;
}
int featureLookupCount = featureTable.LookupCount(Table);
for(ushort lookup = 0; lookup < featureLookupCount; lookup++)
{
workspace.SetFeatureFlag(featureTable.LookupIndex(Table,lookup), feature);
}
}
}
///
/// Critical - This method reads into unsafe cluster map.
///
[SecurityCritical]
private static void GetNextEnabledGlyphRange(
Feature[] FeatureSet, // In: List of features to apply
int featureCount, // In: Actual nubmer of features in FeatureSet
int featureSetOffset, // In: offset of input chars inside feature set
FontTable Table, // Layout table (GSUB or GPOS)
OpenTypeLayoutWorkspace workspace, // workspace with compiled feature set
LangSysTable LangSys, // Language system
FeatureList Features, // List of Features in layout table
ushort lookupIndex, // List of lokups definitions in layout table
int CharCount, // Characters count (i.e. Charmap.Length);
UshortList Charmap, // Character to glyph mapping
int StartChar,
int StartGlyph,
int GlyphRunLength,
out int FirstChar, // First char in enabled range
out int AfterLastChar, // next char after enabled range
out int FirstGlyph, // First char in enabled range
out int AfterLastGlyph, // next char after enabled range
out uint Parameter // applied feature parameter
)
{
FirstChar = int.MaxValue;
AfterLastChar = int.MaxValue;
FirstGlyph = StartGlyph;
AfterLastGlyph = GlyphRunLength;
Parameter = 0;
if (workspace.IsRequiredFeatureFlagSet(lookupIndex))
{
FirstChar = StartChar;
AfterLastChar = CharCount;
FirstGlyph = StartGlyph;
AfterLastGlyph = GlyphRunLength;
return;
}
for(int feature=0; feature < featureCount; feature++)
{
if (!workspace.IsFeatureFlagSet(lookupIndex,feature))
{
continue;
}
Feature featureDescription = FeatureSet[feature];
// Shift values from the feature by specified offset and
// work with these values from here
int featureStart = featureDescription.StartIndex - featureSetOffset;
if (featureStart < 0)
{
featureStart = 0;
}
int featureAfterEnd = featureDescription.StartIndex + featureDescription.Length
- featureSetOffset;
if (featureAfterEnd > CharCount)
{
featureAfterEnd = CharCount;
}
//If feature is disabled there should not be any flag set
Debug.Assert(featureDescription.Parameter != 0);
if (featureAfterEnd <= StartChar)
{
continue;
}
if (featureStart < FirstChar ||
(
featureStart == FirstChar &&
featureAfterEnd >= AfterLastChar
)
)
{
FirstChar = featureStart;
AfterLastChar = featureAfterEnd;
Parameter = featureDescription.Parameter;
continue;
}
}
//No ranges found
if (FirstChar == int.MaxValue)
{
FirstGlyph = GlyphRunLength;
AfterLastGlyph = GlyphRunLength;
}
else
{
if (StartGlyph > Charmap[FirstChar])
FirstGlyph = StartGlyph;
else
FirstGlyph = Charmap[FirstChar];
if (AfterLastChar < CharCount)
AfterLastGlyph = Charmap[AfterLastChar];
else
AfterLastGlyph = GlyphRunLength;
}
}
///
/// Critical - access protected font information (FontTable)
///
[SecurityCritical]
private static void UpdateGlyphFlags(
IOpenTypeFont Font,
GlyphInfoList GlyphInfo,
int FirstGlyph,
int AfterLastGlyph,
bool DoAll,
GlyphFlags FlagToSet
)
{
Debug.Assert( FlagToSet==GlyphFlags.NotChanged ||
FlagToSet==GlyphFlags.Substituted ||
FlagToSet==GlyphFlags.Positioned);
ushort typemask = (ushort)GlyphFlags.GlyphTypeMask;
FontTable gdefTable = Font.GetFontTable(OpenTypeTags.GDEF);
if (!gdefTable.IsPresent)
{
//GDEF(i.e. class def in it) is not present.
//Assign unassigned to all glyphs
for(int i=FirstGlyph;i
/// Critical - Access protected font information (FontTable).
///
[SecurityCritical]
internal static int GetNextGlyphInLookup(
IOpenTypeFont Font, //
GlyphInfoList GlyphInfo, // Glyph run
int FirstGlyph, // Current glyph index
ushort LookupFlags, // Lookup flags to use
int Direction // Search direction (forward/back)
)
{
FontTable gdefTable;
ClassDefTable markAttachClassDef;
//assign them only to avoid error: using unassigned variable
gdefTable = null;
markAttachClassDef = ClassDefTable.InvalidClassDef;
if (LookupFlags==0) return FirstGlyph;
//we will mark classes only if mark filter is set
if ((LookupFlags&(ushort)LookupFlagMarkAttachmentTypeMask)!=0)
{
gdefTable = Font.GetFontTable(OpenTypeTags.GDEF);
if (gdefTable.IsPresent)
{
markAttachClassDef = (new GDEFHeader(0)).GetMarkAttachClassDef(gdefTable);
}
}
UshortList glyphFlags = GlyphInfo.GlyphFlags;
ushort attachClass = (ushort)((LookupFlags&LookupFlagMarkAttachmentTypeMask)>>8);
int glyph;
int glyphRunLength = GlyphInfo.Length;
for(glyph=FirstGlyph; glyph=0; glyph+=Direction)
{
if (
(LookupFlags&LookupFlagIgnoreBases)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Base
) continue;
if (
(LookupFlags&LookupFlagIgnoreMarks)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Mark
) continue;
if (
(LookupFlags&LookupFlagIgnoreLigatures)!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Ligature
) continue;
if (attachClass!=0 &&
(glyphFlags[glyph]&(ushort)GlyphFlags.GlyphTypeMask)==(ushort)GlyphFlags.Mark &&
!markAttachClassDef.IsInvalid &&
attachClass!=markAttachClassDef.GetClass(gdefTable,GlyphInfo.Glyphs[glyph])
) continue;
return glyph;
}
return glyph;
}
///
/// Returns list of the languages, that can not be optimized for simple shaping
///
///
/// Critical - The method reads into raw font table bits
///
[SecurityCritical]
internal static void GetComplexLanguageList(
OpenTypeTags tableTag,
FontTable table,
uint[] featureTagsList,
uint[] glyphBits,
ushort minGlyphId,
ushort maxGlyphId,
out WritingSystem[] complexLanguages,
out int complexLanguageCount
)
{
ScriptList scriptList = new ScriptList(0);
FeatureList featureList = new FeatureList(0);
LookupList lookupList = new LookupList(0);
Debug.Assert(tableTag == OpenTypeTags.GSUB || tableTag == OpenTypeTags.GPOS);
switch (tableTag)
{
case OpenTypeTags.GSUB:
GSUBHeader gsubHeader = new GSUBHeader(0);
scriptList = gsubHeader.GetScriptList(table);
featureList = gsubHeader.GetFeatureList(table);
lookupList = gsubHeader.GetLookupList(table);
break;
case OpenTypeTags.GPOS:
GPOSHeader gposHeader = new GPOSHeader(0);
scriptList = gposHeader.GetScriptList(table);
featureList = gposHeader.GetFeatureList(table);
lookupList = gposHeader.GetLookupList(table);
break;
}
int scriptCount = scriptList.GetScriptCount(table);
int featureCount = featureList.FeatureCount(table);
int lookupCount = lookupList.LookupCount(table);
// We will mark lookups that should be tested.
// At the end, we will have only complex ones marked
uint[] lookupBits = new uint[(lookupCount+31)>>5];
for(int i = 0; i < (lookupCount+31)>>5; i++)
{
lookupBits[i] = 0;
}
// Iterate through list of featuers in the table
for(ushort featureIndex = 0; featureIndex < featureCount; featureIndex++)
{
uint featureTag = (uint)featureList.FeatureTag(table, featureIndex);
bool tagFound = false;
//Search for tag in the list of features in question
for(int j = 0; j < featureTagsList.Length; j++)
{
if (featureTagsList[j] == featureTag)
{
tagFound = true;
break;
}
}
if (tagFound)
{
// We should mark all lookup mapped to this feature
FeatureTable featureTable = featureList.FeatureTable(table, featureIndex);
ushort featureLookupCount = featureTable.LookupCount(table);
for(ushort j = 0; j < featureLookupCount; j++)
{
ushort lookupIndex = featureTable.LookupIndex(table, j);
if (lookupIndex >= lookupCount)
{
//This should be invalid font. Lookup associated with the feature is not in lookup array.
throw new FileFormatException();
}
lookupBits[lookupIndex>>5] |= (uint)(1 << (lookupIndex%32));
}
}
}
//
//
//Now test all marked lookups
for(ushort lookupIndex = 0; lookupIndex < lookupCount; lookupIndex++)
{
if ((lookupBits[lookupIndex>>5] & (1 << (lookupIndex%32))) == 0)
{
continue;
}
LookupTable lookup = lookupList.Lookup(table,lookupIndex);
ushort lookupType = lookup.LookupType();
ushort subtableCount = lookup.SubTableCount();
bool lookupIsCovered = false;
ushort originalLookupType = lookupType; // We need it to recover,
// if extension lookup updated lookupFormat
for(ushort subtableIndex = 0;
!lookupIsCovered && subtableIndex < subtableCount;
subtableIndex++)
{
lookupType = originalLookupType;
int subtableOffset = lookup.SubtableOffset(table, subtableIndex);
switch (tableTag)
{
case OpenTypeTags.GSUB:
{
if (lookupType == 7)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(table);
subtableOffset = extension.LookupSubtableOffset(table);
}
switch (lookupType)
{
case 1: //SingleSubst
SingleSubstitutionSubtable singleSub =
new SingleSubstitutionSubtable(subtableOffset);
lookupIsCovered = singleSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 2: //MultipleSubst
MultipleSubstitutionSubtable multipleSub =
new MultipleSubstitutionSubtable(subtableOffset);
lookupIsCovered = multipleSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 3: //AlternateSubst
AlternateSubstitutionSubtable alternateSub =
new AlternateSubstitutionSubtable(subtableOffset);
lookupIsCovered = alternateSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 4: //Ligature subst
LigatureSubstitutionSubtable ligaSub =
new LigatureSubstitutionSubtable(subtableOffset);
lookupIsCovered = ligaSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 5: //ContextualSubst
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
lookupIsCovered = contextSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 6: //ChainingSubst
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
lookupIsCovered = chainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 7: //Extension lookup
Debug.Assert(false,"Ext.Lookup processed earlier!");
break;
case 8: //ReverseCahiningSubst
ReverseChainingSubtable reverseChainingSub =
new ReverseChainingSubtable(subtableOffset);
lookupIsCovered = reverseChainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
default:
// Unknown format
lookupIsCovered = true;
break;
}
break;
}
case OpenTypeTags.GPOS:
{
if (lookupType == 9)
{
ExtensionLookupTable extension =
new ExtensionLookupTable(subtableOffset);
lookupType = extension.LookupType(table);
subtableOffset = extension.LookupSubtableOffset(table);
}
switch (lookupType)
{
case 1: //SinglePos
SinglePositioningSubtable singlePos =
new SinglePositioningSubtable(subtableOffset);
lookupIsCovered = singlePos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 2: //PairPos
PairPositioningSubtable pairPos =
new PairPositioningSubtable(subtableOffset);
lookupIsCovered = pairPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 3: // CursivePos
// Under construction
CursivePositioningSubtable cursivePositioningSubtable =
new CursivePositioningSubtable(subtableOffset);
lookupIsCovered = cursivePositioningSubtable.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 4: //MarkToBasePos
MarkToBasePositioningSubtable markToBasePos =
new MarkToBasePositioningSubtable(subtableOffset);
lookupIsCovered = markToBasePos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 5: //MarkToLigaturePos
// Under construction
MarkToLigaturePositioningSubtable markToLigaPos =
new MarkToLigaturePositioningSubtable(subtableOffset);
lookupIsCovered = markToLigaPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 6: //MarkToMarkPos
MarkToMarkPositioningSubtable markToMarkPos =
new MarkToMarkPositioningSubtable(subtableOffset);
lookupIsCovered = markToMarkPos.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 7: // Contextual
ContextSubtable contextSub =
new ContextSubtable(subtableOffset);
lookupIsCovered = contextSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 8: // Chaining
ChainingSubtable chainingSub =
new ChainingSubtable(subtableOffset);
lookupIsCovered = chainingSub.IsLookupCovered(table,glyphBits,minGlyphId,maxGlyphId);
break;
case 9: //Extension lookup
Debug.Assert(false,"Ext.Lookup processed earlier!");
break;
default:
// Unknown format
lookupIsCovered = true;
break;
}
break;
}
default:
Debug.Assert(false,"Unknown OpenType layout table!");
break;
}
}
if (!lookupIsCovered)
{
// Clean the flag
lookupBits[lookupIndex>>5] &= ~(uint)(1 << (lookupIndex%32));
}
}
// Check if we have any lookup left
bool complexLookupFound = false;
for(int i = 0; i < (lookupCount+31)>>5; i++)
{
if (lookupBits[i] != 0)
{
complexLookupFound = true;
break;
}
}
if (!complexLookupFound)
{
// There are no complex lookups
complexLanguages = null;
complexLanguageCount = 0;
return;
}
// Now go through all langauages and fill the list
complexLanguages = new WritingSystem[10];
complexLanguageCount = 0;
for(ushort scriptIndex = 0; scriptIndex < scriptCount; scriptIndex++)
{
ScriptTable scriptTable = scriptList.GetScriptTable(table, scriptIndex);
uint scriptTag = scriptList.GetScriptTag(table, scriptIndex);
ushort langSysCount = scriptTable.GetLangSysCount(table);
if (scriptTable.IsDefaultLangSysExists(table))
{
AppendLangSys(scriptTag, (uint)OpenTypeTags.dflt,
scriptTable.GetDefaultLangSysTable(table),
featureList,
table,
featureTagsList,
lookupBits,
ref complexLanguages,
ref complexLanguageCount
);
}
for(ushort langSysIndex = 0; langSysIndex < langSysCount; langSysIndex++)
{
uint langSysTag = scriptTable.GetLangSysTag(table, langSysIndex);
AppendLangSys(scriptTag, langSysTag,
scriptTable.GetLangSysTable(table, langSysIndex),
featureList,
table,
featureTagsList,
lookupBits,
ref complexLanguages,
ref complexLanguageCount
);
}
}
}
///
/// Critical - The method reads into raw font table bits.
///
[SecurityCritical]
private static void AppendLangSys(
uint scriptTag,
uint langSysTag,
LangSysTable langSysTable,
FeatureList featureList,
FontTable table,
uint[] featureTagsList,
uint[] lookupBits,
ref WritingSystem[] complexLanguages,
ref int complexLanguageCount
)
{
ushort featureCount = langSysTable.FeatureCount(table);
bool complexFeatureFound = false;
//
for(ushort i = 0; !complexFeatureFound && i < featureCount; i++)
{
ushort featureIndex = langSysTable.GetFeatureIndex(table, i);
uint featureTag = featureList.FeatureTag(table,featureIndex);
bool tagFound = false;
for(int j = 0; !complexFeatureFound && j < featureTagsList.Length; j++)
{
if (featureTagsList[j] == featureTag)
{
tagFound = true;
break;
}
}
if (tagFound)
{
// We should check if any of lookups is complex
FeatureTable featureTable = featureList.FeatureTable(table, featureIndex);
ushort featureLookupCount = featureTable.LookupCount(table);
for(ushort j = 0; j < featureLookupCount; j++)
{
ushort lookupIndex = featureTable.LookupIndex(table, j);
if ((lookupBits[lookupIndex>>5] & (1 << (lookupIndex%32))) != 0)
{
complexFeatureFound = true;
break;
}
}
}
}
if (complexFeatureFound)
{
if (complexLanguages.Length == complexLanguageCount)
{
WritingSystem[] newComplexLanguages =
new WritingSystem[complexLanguages.Length * 3 /2];
for(int i = 0; i < complexLanguages.Length; i++)
{
newComplexLanguages[i] = complexLanguages[i];
}
complexLanguages = newComplexLanguages;
}
complexLanguages[complexLanguageCount].scriptTag = scriptTag;
complexLanguages[complexLanguageCount].langSysTag = langSysTag;
complexLanguageCount++;
}
}
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GSUBHeader
{
private const int offsetScriptList = 4;
private const int offsetFeatureList = 6;
private const int offsetLookupList = 8;
public ScriptList GetScriptList(FontTable Table)
{
return new ScriptList(offset+Table.GetOffset(offset+offsetScriptList));
}
public FeatureList GetFeatureList(FontTable Table)
{
return new FeatureList(offset+Table.GetOffset(offset+offsetFeatureList));
}
public LookupList GetLookupList(FontTable Table)
{
return new LookupList(offset+Table.GetOffset(offset+offsetLookupList));
}
public GSUBHeader(int Offset)
{
offset = Offset;
}
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GPOSHeader
{
private const int offsetScriptList = 4;
private const int offsetFeatureList = 6;
private const int offsetLookupList = 8;
public ScriptList GetScriptList(FontTable Table)
{
return new ScriptList(offset+Table.GetOffset(offset+offsetScriptList));
}
public FeatureList GetFeatureList(FontTable Table)
{
return new FeatureList(offset+Table.GetOffset(offset+offsetFeatureList));
}
public LookupList GetLookupList(FontTable Table)
{
return new LookupList(offset+Table.GetOffset(offset+offsetLookupList));
}
public GPOSHeader(int Offset)
{
offset = Offset;
}
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct GDEFHeader
{
private const int offsetGlyphClassDef = 4;
private const int offsetGlyphAttachList = 6;
private const int offsetLigaCaretList = 8;
private const int offsetMarkAttachClassDef = 10;
public ClassDefTable GetGlyphClassDef(FontTable Table)
{
//There is only one place where GDEF classdef is retireved -
// UpdateGlyphFlags. We will check if GDEF is present there
Invariant.Assert(Table.IsPresent);
return new ClassDefTable(offset + Table.GetOffset(offset + offsetGlyphClassDef));
}
// ///
// /// Under construction
// /// Glyph attachment points list
// ///
// ///
// ///
// /// Under construction
// /// Ligature caret positioning data
// ///
// ///
// ///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ScriptList
{
private const int offsetScriptCount = 0;
private const int offsetScriptRecordArray = 2;
private const int sizeScriptRecord = 6;
private const int offsetScriptRecordTag = 0;
private const int offsetScriptRecordOffset = 4;
public ScriptTable FindScript(FontTable Table, uint Tag)
{
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ScriptTable
{
private const int offsetDefaultLangSys = 0;
private const int offsetLangSysCount = 2;
private const int offsetLangSysRecordArray = 4;
private const int sizeLangSysRecord = 6;
private const int offsetLangSysRecordTag = 0;
private const int offsetLangSysRecordOffset = 4;
public LangSysTable FindLangSys(FontTable Table, uint Tag)
{
if (IsNull)
{
return new LangSysTable(FontTable.InvalidOffset);
}
if ((OpenTypeTags)Tag==OpenTypeTags.dflt)
{
if (IsDefaultLangSysExists(Table))
return new LangSysTable(offset +
Table.GetOffset(offset + offsetDefaultLangSys));
return new LangSysTable(FontTable.InvalidOffset);
}
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LangSysTable
{
private const int offsetRequiredFeature = 2;
private const int offsetFeatureCount = 4;
private const int offsetFeatureIndexArray = 6;
private const int sizeFeatureIndex = 2;
public FeatureTable FindFeature(FontTable Table, FeatureList Features, uint FeatureTag)
{
ushort featureCount = FeatureCount(Table);
for(ushort i=0;i
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct FeatureList
{
private const int offsetFeatureCount = 0;
private const int offsetFeatureRecordArray = 2;
private const int sizeFeatureRecord = 6;
private const int offsetFeatureRecordTag = 0;
private const int offsetFeatureRecordOffset = 4;
public ushort FeatureCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFeatureCount);
}
public uint FeatureTag(FontTable Table,ushort Index)
{
return Table.GetUInt(offset + offsetFeatureRecordArray +
Index * sizeFeatureRecord +
offsetFeatureRecordTag);
}
public FeatureTable FeatureTable(FontTable Table,ushort Index)
{
return new FeatureTable(offset+Table.GetUShort(offset +
offsetFeatureRecordArray +
Index * sizeFeatureRecord +
offsetFeatureRecordOffset));
}
public FeatureList(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct FeatureTable
{
private const int offsetLookupCount = 2;
private const int offsetLookupIndexArray = 4;
private const int sizeLookupIndex = 2;
public ushort LookupCount(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupCount);
}
public ushort LookupIndex(FontTable Table,ushort Index)
{
return Table.GetUShort(offset + offsetLookupIndexArray + Index*sizeLookupIndex);
}
public FeatureTable(int Offset){ offset = Offset; }
public bool IsNull { get{ return (offset==FontTable.InvalidOffset); } }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LookupList
{
private const int offsetLookupCount = 0;
private const int LookupOffsetArray = 2;
private const int sizeLookupOffset = 2;
public ushort LookupCount(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupCount);
}
public LookupTable Lookup(FontTable Table, ushort Index)
{
return new LookupTable(Table, offset + Table.GetUShort(offset + LookupOffsetArray +
Index * sizeLookupOffset));
}
public LookupList(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct LookupTable
{
private const int offsetLookupType = 0;
private const int offsetLookupFlags = 2;
private const int offsetSubtableCount = 4;
private const int offsetSubtableArray = 6;
private const int sizeSubtableOffset = 2;
public ushort LookupType()
{
return lookupType;
}
public ushort LookupFlags()
{
return lookupFlags;
}
public ushort SubTableCount()
{
return subtableCount;
}
public int SubtableOffset(FontTable Table, ushort Index)
{
Debug.Assert(Index < SubTableCount());
return offset+Table.GetOffset(offset + offsetSubtableArray +
Index*sizeSubtableOffset);
}
public LookupTable(FontTable table, int Offset)
{
offset = Offset;
lookupType = table.GetUShort(offset + offsetLookupType);
lookupFlags = table.GetUShort(offset + offsetLookupFlags);
subtableCount = table.GetUShort(offset + offsetSubtableCount);
}
private int offset;
private ushort lookupType;
private ushort lookupFlags;
private ushort subtableCount;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct CoverageTable
{
private const int offsetFormat = 0;
private const int offsetFormat1GlyphCount = 2;
private const int offsetFormat1GlyphArray = 4;
private const int sizeFormat1GlyphId = 2;
private const int offsetFormat2RangeCount = 2;
private const int offsetFormat2RangeRecordArray = 4;
private const int sizeFormat2RangeRecord = 6;
private const int offsetFormat2RangeRecordStart = 0;
private const int offsetFormat2RangeRecordEnd = 2;
private const int offsetFormat2RangeRecordStartIndex = 4;
public ushort Format(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat);
}
public ushort Format1GlyphCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1GlyphCount);
}
public ushort Format1Glyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat1GlyphArray +
Index*sizeFormat1GlyphId);
}
public ushort Format2RangeCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat2RangeCount);
}
public ushort Format2RangeStartGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStart);
}
public ushort Format2RangeEndGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordEnd);
}
public ushort Format2RangeStartCoverageIndex(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStartIndex);
}
public int GetGlyphIndex(FontTable Table, ushort glyph)
{
switch (Format(Table))
{
case 1: // Coverage array
{
ushort lowIndex = 0;
ushort highIndex = Format1GlyphCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
ushort middleGlyph = Format1Glyph(Table,middleIndex);
if (glyph < middleGlyph)
{
highIndex = middleIndex;
}
else if (glyph > middleGlyph)
{
lowIndex = (ushort)(middleIndex+1);
}
else
{
return middleIndex;
}
}
return -1;
}
case 2: //Glyph Ranges
{
ushort lowIndex = 0;
ushort highIndex = Format2RangeCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
if (glyph < Format2RangeStartGlyph(Table, middleIndex))
{
highIndex = middleIndex;
}
else if (glyph > Format2RangeEndGlyph(Table, middleIndex))
{
lowIndex = (ushort)(middleIndex + 1);
}
else
{
return (glyph - Format2RangeStartGlyph(Table,middleIndex))
+ Format2RangeStartCoverageIndex(Table,middleIndex);
}
}
return -1;
}
default:
//unknown format. Return NoMatch.
return -1;
}
}
public bool IsAnyGlyphCovered(
FontTable table,
uint[] glyphBits,
ushort minGlyphId,
ushort maxGlyphId)
{
switch (Format(table))
{
case 1: // Coverage array
{
ushort glyphCount = Format1GlyphCount(table);
if (glyphCount == 0) return false;
ushort firstGlyphId = Format1Glyph(table, 0);
ushort lastGlyphId = Format1Glyph(table, (ushort)(glyphCount - 1));
if (maxGlyphId < firstGlyphId || minGlyphId > lastGlyphId) return false;
for(ushort i = 0; i < glyphCount; i++)
{
ushort glyphId = Format1Glyph(table, i);
if (glyphId <= maxGlyphId &&
glyphId >= minGlyphId &&
(glyphBits[glyphId >> 5] & (1 << (glyphId % 32))) != 0
)
{
return true;
}
}
return false;
}
case 2: //Glyph Ranges
{
ushort rangeCount = Format2RangeCount(table);
if (rangeCount == 0) return false;
ushort firstGlyphId = Format2RangeStartGlyph(table,0);
ushort lastGlyphId = Format2RangeEndGlyph(table, (ushort)(rangeCount - 1));
if (maxGlyphId < firstGlyphId || minGlyphId > lastGlyphId) return false;
for (ushort rangeIndex = 0; rangeIndex < rangeCount; rangeIndex++)
{
ushort startGlyphId = Format2RangeStartGlyph(table,rangeIndex);
ushort endGlyphId = Format2RangeEndGlyph(table, rangeIndex);
for (ushort glyphId = startGlyphId; glyphId <= endGlyphId; glyphId++)
{
if (glyphId <= maxGlyphId &&
glyphId >= minGlyphId &&
(glyphBits[glyphId >> 5] & (1 << (glyphId % 32))) != 0
)
{
return true;
}
}
}
return false;
}
default:
//unknown format. Return true.
return true;
}
}
public static CoverageTable InvalidCoverage
{
get { return new CoverageTable(-1); }
}
public bool IsInvalid
{
get { return offset == -1; }
}
public CoverageTable(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ClassDefTable
{
private const int offsetFormat = 0;
private const int offsetFormat1StartGlyph = 2;
private const int offsetFormat1GlyphCount = 4;
private const int offsetFormat1ClassValueArray = 6;
private const int sizeFormat1ClassValue = 2;
private const int offsetFormat2RangeCount = 2;
private const int offsetFormat2RangeRecordArray = 4;
private const int sizeFormat2RangeRecord = 6;
private const int offsetFormat2RangeRecordStart = 0;
private const int offsetFormat2RangeRecordEnd = 2;
private const int offsetFormat2RangeRecordClass = 4;
private ushort Format(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat);
}
private ushort Format1StartGlyph(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1StartGlyph);
}
private ushort Format1GlyphCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat1GlyphCount);
}
private ushort Format1ClassValue(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat1ClassValueArray +
Index*sizeFormat1ClassValue);
}
private ushort Format2RangeCount(FontTable Table)
{
return Table.GetUShort(offset + offsetFormat2RangeCount);
}
private ushort Format2RangeStartGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordStart);
}
private ushort Format2RangeEndGlyph(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordEnd);
}
private ushort Format2RangeClassValue(FontTable Table, ushort Index)
{
return Table.GetUShort(offset + offsetFormat2RangeRecordArray +
Index*sizeFormat2RangeRecord +
offsetFormat2RangeRecordClass);
}
public ushort GetClass(FontTable Table, ushort glyph)
{
//PERF: binary search!!!
switch (Format(Table))
{
case 1: // ClassDef array
{
ushort startGlyph = Format1StartGlyph(Table);
ushort glyphCount = Format1GlyphCount(Table);
if (glyph >= startGlyph && (glyph - startGlyph) < glyphCount)
return Format1ClassValue(Table,(ushort)(glyph - startGlyph));
else
return 0;
}
case 2: //ClassDef Ranges
{
ushort lowIndex = 0;
ushort highIndex = Format2RangeCount(Table);
while(lowIndex < highIndex)
{
ushort middleIndex = (ushort)((lowIndex + highIndex) >> 1);
if (glyph < Format2RangeStartGlyph(Table, middleIndex))
{
highIndex = middleIndex;
}
else if (glyph > Format2RangeEndGlyph(Table, middleIndex))
{
lowIndex = (ushort)(middleIndex + 1);
}
else
{
return Format2RangeClassValue(Table,middleIndex);
}
}
return 0;
}
default:
//unknown format. Return default: 0
return 0;
}
}
public static ClassDefTable InvalidClassDef
{
get { return new ClassDefTable(-1); }
}
public bool IsInvalid
{
get { return offset == -1; }
}
public ClassDefTable(int Offset) { offset = Offset; }
private int offset;
}
///
/// Critical - Everything in this struct is considered critical
/// because they either operate on raw font table bits or unsafe pointers.
///
[SecurityCritical(SecurityCriticalScope.Everything)]
internal struct ExtensionLookupTable
{
private const int offsetFormat = 0;
private const int offsetLookupType = 2;
private const int offsetExtensionOffset = 4;
internal ushort LookupType(FontTable Table)
{
return Table.GetUShort(offset + offsetLookupType);
}
internal int LookupSubtableOffset(FontTable Table)
{
return offset + (int)Table.GetUInt(offset + offsetExtensionOffset);
}
public ExtensionLookupTable(int Offset) { offset = Offset; }
private int offset;
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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- NGCPageContentCollectionSerializerAsync.cs
- XPathBinder.cs
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- smtppermission.cs
- EmissiveMaterial.cs
- DrawingContextDrawingContextWalker.cs
- ReadWriteControlDesigner.cs
- Cursor.cs
- LoginView.cs
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- NumericExpr.cs
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- AssemblyHash.cs
- XmlWrappingReader.cs
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- XmlElement.cs
- BindingWorker.cs
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- ProjectionCamera.cs
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- PropertyItem.cs
- CompilationLock.cs
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