void Layout(GlyphIndexList glyphs)
{
if (_needPlanUpdate)
{
UpdateLayoutPlan();
}
//[C]
//----------------------------------------------
//glyph substitution
if (_gsub != null && glyphs.Count > 0)
{
//TODO: review perf here
_gsub.EnableLigation = this.EnableLigature;
_gsub.EnableComposition = this.EnableComposition;
_gsub.DoSubstitution(glyphs);
}
//----------------------------------------------
//after glyph substitution,
//number of input glyph MAY changed (increase or decrease).***
//so count again.
int finalGlyphCount = glyphs.Count;
//----------------------------------------------
//[D]
//glyph position
_glyphPositions.Clear();
_glyphPositions.Typeface = _typeface;
for (int i = 0; i < finalGlyphCount; ++i)
{
//at this stage _inputGlyphs and _glyphPositions
//has member 1:1
ushort glyIndex, input_codepointOffset, input_mapLen;
glyphs.GetGlyphIndexAndMap(i, out glyIndex, out input_codepointOffset, out input_mapLen);
//
Glyph orgGlyph = _typeface.GetGlyphByIndex(glyIndex);
//this is original value WITHOUT fit-to-grid adjust
_glyphPositions.AddGlyph(input_codepointOffset, glyIndex, orgGlyph);
}
PositionTechnique posTech = this.PositionTechnique;
if (_gpos != null && glyphs.Count > 1 && posTech == PositionTechnique.OpenFont)
{
_gpos.DoGlyphPosition(_glyphPositions);
}
//----------------------------------------------
//at this point, all positions are layouted at its original scale ***
//then we will scale it to target scale later
//----------------------------------------------
}