protected override Box CreateBoxCore(TexEnvironment environment)
{
var texFont = environment.MathFont;
var style = environment.Style;
// Calculate minimum clearance amount.
double clearance;
var defaultRuleThickness = texFont.GetDefaultLineThickness(style);
if (style < TexStyle.Text)
{
clearance = texFont.GetXHeight(style, texFont.GetCharInfo(sqrtSymbol, style).Value.FontId);
}
else
{
clearance = defaultRuleThickness;
}
clearance = defaultRuleThickness + Math.Abs(clearance) / 4;
// Create box for base atom, in cramped style.
var baseBox = this.BaseAtom.CreateBox(environment.GetCrampedStyle());
// Create box for radical sign.
var totalHeight = baseBox.Height + baseBox.Depth;
var radicalSignBox = DelimiterFactory.CreateBox(sqrtSymbol, totalHeight + clearance + defaultRuleThickness,
environment, Source);
radicalSignBox.Source = Source;
// Add half of excess height to clearance.
var delta = radicalSignBox.Depth - (totalHeight + clearance);
clearance += delta / 2;
// Create box for square-root containing base box.
radicalSignBox.Shift = -(baseBox.Height + clearance);
var overBar = new OverBar(environment, baseBox, clearance, radicalSignBox.Height);
overBar.Shift = -(baseBox.Height + clearance + defaultRuleThickness);
var radicalContainerBox = new HorizontalBox(radicalSignBox);
radicalContainerBox.Add(overBar);
// If atom is simple radical, just return square-root box.
if (this.DegreeAtom == null)
{
return(radicalContainerBox);
}
// Atom is complex radical (nth-root).
// Create box for root atom.
var rootBox = this.DegreeAtom.CreateBox(environment.GetRootStyle());
var bottomShift = scale * (radicalContainerBox.Height + radicalContainerBox.Depth);
rootBox.Shift = radicalContainerBox.Depth - rootBox.Depth - bottomShift;
// Create result box.
var resultBox = new HorizontalBox();
// Add box for negative kern.
var negativeKern = new SpaceAtom(null, TexUnit.Mu, -10, 0, 0).CreateBox(environment);
var xPos = rootBox.Width + negativeKern.Width;
if (xPos < 0)
{
resultBox.Add(new StrutBox(-xPos, 0, 0, 0));
}
resultBox.Add(rootBox);
resultBox.Add(negativeKern);
resultBox.Add(radicalContainerBox);
return(resultBox);
}