void LayoutWithoutHorizontalFitAlign(IGlyphPositions posStream, GlyphPlanList outputGlyphPlanList)
{
//the default OpenFont layout without fit-to-writing alignment
int finalGlyphCount = posStream.Count;
float pxscale = _typeface.CalculateScaleToPixelFromPointSize(this._fontSizeInPoints);
double cx = 0;
short cy = 0;
for (int i = 0; i < finalGlyphCount; ++i)
{
short offsetX, offsetY, advW; //all from pen-pos
ushort glyphIndex = posStream.GetGlyph(i, out offsetX, out offsetY, out advW);
float s_advW = advW * pxscale;
float exact_x = (float)(cx + offsetX * pxscale);
float exact_y = (float)(cy + offsetY * pxscale);
//outputGlyphPlanList.Append(new GlyphPlan(
// glyphIndex,
// exact_x,
// exact_y,
// advW)); //old?
outputGlyphPlanList.Append(new GlyphPlan(
glyphIndex,
exact_x,
exact_y,
s_advW));
cx += s_advW;
}
}
public void Layout(IGlyphPositions posStream, GlyphPlanList outputGlyphPlanList)
{
if (!UseWithLcdSubPixelRenderingTechnique)
{
//layout without fit to alignment direction
LayoutWithoutHorizontalFitAlign(posStream, outputGlyphPlanList);
return; //early exit
}
//------------------------------
int finalGlyphCount = posStream.Count;
float pxscale = _typeface.CalculateScaleToPixelFromPointSize(this._fontSizeInPoints);
#if DEBUG
float dbug_onepx = 1 / pxscale;
#endif
//
int cx = 0;
short cy = 0;
//
//at this state, we need exact info at this specific pxscale
//
_hintedFontStore.SetFont(_typeface, this._fontSizeInPoints);
FineABC current_ABC = new FineABC();
FineABC prev_ABC = new FineABC();
for (int i = 0; i < finalGlyphCount; ++i)
{
short offsetX, offsetY, advW; //all from pen-pos
ushort glyphIndex = posStream.GetGlyph(i, out offsetX, out offsetY, out advW);
GlyphControlParameters controlPars = _hintedFontStore.GetControlPars(glyphIndex);
current_ABC.SetData(pxscale, controlPars, offsetX, offsetY, (ushort)advW);
//-------------------------------------------------------------
if (i > 0)
{
//inter-glyph space
//ideal space
float ideal_space = prev_ABC.s_c + current_ABC.s_a;
//actual space
float actual_space = prev_ABC.m_c + current_ABC.m_a;
if (ideal_space < 0)
{
//f-f
//f-o
if (prev_ABC.s_c < 0)
{
ideal_space = 0 + current_ABC.s_a;
}
if (ideal_space < 0)
{
ideal_space = 0;
}
}
if (ideal_space >= 0)
{
//m-a
//i-i
//o-p
if (actual_space > 1.5 && actual_space - 0.5 > ideal_space)
{
cx--;
}
else
{
if (actual_space < ideal_space)
{
if (prev_ABC.final_advW + prev_ABC.m_c_adjust < prev_ABC.m_max)
{
cx += current_ABC.m_a_adjust;
}
}
else
{
if (prev_ABC.final_advW - prev_ABC.m_c + prev_ABC.m_c_adjust > prev_ABC.m_max)
{
cx += prev_ABC.m_c_adjust;
}
}
}
}
else
{
//this should not occur?
}
}
//-------------------------------------------------------------
float exact_x = (float)(cx + current_ABC.s_offsetX);
float exact_y = (float)(cy + current_ABC.s_offsetY);
//check if the current position can create a sharp glyph
int exact_x_floor = (int)exact_x;
float x_offset_to_fit = current_ABC.s_avg_x_ToFit;
float final_x = exact_x_floor + x_offset_to_fit;
if (UseWithLcdSubPixelRenderingTechnique)
{
final_x += 0.33f;
}
outputGlyphPlanList.Append(new GlyphPlan(
glyphIndex,
final_x,
exact_y,
current_ABC.final_advW));
//
//
cx += current_ABC.final_advW;
//-----------------------------------------------
prev_ABC = current_ABC;//copy current to prev
#if DEBUG
prev_ABC.dbugIsPrev = true;
#endif
// Console.WriteLine(exact_x + "+" + (x_offset_to_fit) + "=>" + final_x);
}
}