///<summary>
/// Internal method to test layout tables if they are uitable for fast path.
/// Returns list of script-langauge pairs that are not optimizable.
///</summary>
internal static OpenTypeLayoutResult GetComplexLanguageList(
IOpenTypeFont Font, //In: Font access interface
uint[] featureList, //In: Feature to look in
uint[] glyphBits,
ushort minGlyphId,
ushort maxGlyphId,
out WritingSystem[] complexLanguages
// Out: List of script/langauge pair
// that are not optimizable
)
{
try
{
WritingSystem[] gsubComplexLanguages = null;
WritingSystem[] gposComplexLanguages = null;
int gsubComplexLanguagesCount = 0;
int gposComplexLanguagesCount = 0;
FontTable GsubTable = Font.GetFontTable(OpenTypeTags.GSUB);
FontTable GposTable = Font.GetFontTable(OpenTypeTags.GPOS);
if (GsubTable.IsPresent)
{
LayoutEngine.GetComplexLanguageList(
OpenTypeTags.GSUB,
GsubTable,
featureList,
glyphBits,
minGlyphId,
maxGlyphId,
out gsubComplexLanguages,
out gsubComplexLanguagesCount
);
}
if (GposTable.IsPresent)
{
LayoutEngine.GetComplexLanguageList(
OpenTypeTags.GPOS,
GposTable,
featureList,
glyphBits,
minGlyphId,
maxGlyphId,
out gposComplexLanguages,
out gposComplexLanguagesCount
);
}
if (gsubComplexLanguages == null && gposComplexLanguages == null)
{
complexLanguages = null;
return(OpenTypeLayoutResult.Success);
}
// Both tables have complex scrips, merge results
// Count gpos unique Languages
// and pack them at the same time
// so we do not research them again.
int gposNewLanguages = 0, i, j;
for (i = 0; i < gposComplexLanguagesCount; i++)
{
bool foundInGsub = false;
for (j = 0; j < gsubComplexLanguagesCount; j++)
{
if (gsubComplexLanguages[j].scriptTag == gposComplexLanguages[i].scriptTag &&
gsubComplexLanguages[j].langSysTag == gposComplexLanguages[i].langSysTag
)
{
foundInGsub = true;
break;
}
;
}
if (!foundInGsub)
{
if (gposNewLanguages < i)
{
gposComplexLanguages[gposNewLanguages] = gposComplexLanguages[i];
}
gposNewLanguages++;
}
}
//realloc array for merged results, merge both arrays
complexLanguages = new WritingSystem[gsubComplexLanguagesCount + gposNewLanguages];
for (i = 0; i < gsubComplexLanguagesCount; i++)
{
complexLanguages[i] = gsubComplexLanguages[i];
}
for (i = 0; i < gposNewLanguages; i++)
{
complexLanguages[gsubComplexLanguagesCount + i] = gposComplexLanguages[i];
}
return(OpenTypeLayoutResult.Success);
}
catch (FileFormatException)
{
complexLanguages = null;
return(OpenTypeLayoutResult.BadFontTable);
}
}
