public override Box CreateBox(TexEnvironment environment)
{
var texFont = environment.TexFont;
var style = environment.Style;
// Create box for base atom.
var baseBox = BaseAtom is null ? StrutBox.Empty : BaseAtom.CreateBox(environment.GetCrampedStyle());
var skew = 0d;
if (BaseAtom is CharSymbol)
{
skew = texFont.GetSkew(((CharSymbol)BaseAtom).GetCharFont(texFont), style);
}
// Find character of best scale for accent symbol.
var accentChar = texFont.GetCharInfo(AccentAtom.Name, style);
while (texFont.HasNextLarger(accentChar))
{
var nextLargerChar = texFont.GetNextLargerCharInfo(accentChar, style);
if (nextLargerChar.Metrics.Width > baseBox.Width)
{
break;
}
accentChar = nextLargerChar;
}
var resultBox = new VerticalBox();
// Create and add box for accent symbol.
Box accentBox;
var accentItalicWidth = accentChar.Metrics.Italic;
if (accentItalicWidth > TexUtilities.FloatPrecision)
{
accentBox = new HorizontalBox(new CharBox(environment, accentChar));
accentBox.Add(new StrutBox(accentItalicWidth, 0, 0, 0));
}
else
{
accentBox = new CharBox(environment, accentChar);
}
resultBox.Add(accentBox);
var delta = Math.Min(baseBox.Height, texFont.GetXHeight(style, accentChar.FontId));
resultBox.Add(new StrutBox(0, -delta, 0, 0));
// Centre and add box for base atom. Centre base box and accent box with respect to each other.
var boxWidthsDiff = (baseBox.Width - accentBox.Width) / 2;
accentBox.Shift = skew + Math.Max(boxWidthsDiff, 0);
if (boxWidthsDiff < 0)
{
baseBox = new HorizontalBox(baseBox, accentBox.Width, TexAlignment.Center);
}
resultBox.Add(baseBox);
// Adjust height and depth of result box.
var depth = baseBox.Depth;
var totalHeight = resultBox.Height + resultBox.Depth;
resultBox.Depth = depth;
resultBox.Height = totalHeight - depth;
return(resultBox);
}
public override Box CreateBox(TexEnvironment environment)
{
var texFont = environment.TexFont;
var style = environment.Style;
// Create box for base atom.
var baseBox = (BaseAtom is null ? StrutBox.Empty : BaseAtom.CreateBox(environment));
if (SubscriptAtom is null && SuperscriptAtom is null)
{
return(baseBox);
}
// Create result box.
var resultBox = new HorizontalBox(baseBox);
// Get last font used or default Mu font.
var lastFontId = baseBox.GetLastFontId();
if (lastFontId == TexFontUtilities.NoFontId)
{
lastFontId = texFont.GetMuFontId();
}
var subscriptStyle = environment.GetSubscriptStyle();
var superscriptStyle = environment.GetSuperscriptStyle();
// Set delta value and preliminary shift-up and shift-down amounts depending on type of base atom.
var delta = 0d;
double shiftUp, shiftDown;
if (BaseAtom is AccentedAtom)
{
var accentedBox = ((AccentedAtom)BaseAtom).BaseAtom.CreateBox(environment.GetCrampedStyle());
shiftUp = accentedBox.Height - texFont.GetSupDrop(superscriptStyle.Style);
shiftDown = accentedBox.Depth + texFont.GetSubDrop(subscriptStyle.Style);
}
else if (BaseAtom is SymbolAtom && BaseAtom.Type == TexAtomType.BigOperator)
{
var charInfo = texFont.GetCharInfo(((SymbolAtom)BaseAtom).Name, style);
if (style < TexStyle.Text && texFont.HasNextLarger(charInfo))
{
charInfo = texFont.GetNextLargerCharInfo(charInfo, style);
}
var charBox = new CharBox(environment, charInfo);
charBox.Shift = -(charBox.Height + charBox.Depth) / 2 - environment.TexFont.GetAxisHeight(
environment.Style);
resultBox = new HorizontalBox(charBox);
delta = charInfo.Metrics.Italic;
if (delta > TexUtilities.FloatPrecision && SubscriptAtom is null)
{
resultBox.Add(new StrutBox(delta, 0, 0, 0));
}
shiftUp = resultBox.Height - texFont.GetSupDrop(superscriptStyle.Style);
shiftDown = resultBox.Depth + texFont.GetSubDrop(subscriptStyle.Style);
}
else if (BaseAtom is CharSymbol)
{
var charFont = ((CharSymbol)BaseAtom).GetCharFont(texFont);
if (!((CharSymbol)BaseAtom).IsTextSymbol || !texFont.HasSpace(charFont.FontId))
{
delta = texFont.GetCharInfo(charFont, style).Metrics.Italic;
}
if (delta > TexUtilities.FloatPrecision && SubscriptAtom is null)
{
resultBox.Add(new StrutBox(delta, 0, 0, 0));
delta = 0;
}
shiftUp = 0;
shiftDown = 0;
}
else
{
shiftUp = baseBox.Height - texFont.GetSupDrop(superscriptStyle.Style);
shiftDown = baseBox.Depth + texFont.GetSubDrop(subscriptStyle.Style);
}
Box superscriptBox = null;
Box superscriptContainerBox = null;
Box subscriptBox = null;
Box subscriptContainerBox = null;
if (SuperscriptAtom != null)
{
// Create box for superscript atom.
superscriptBox = SuperscriptAtom.CreateBox(superscriptStyle);
superscriptContainerBox = new HorizontalBox(superscriptBox);
// Add box for script space.
superscriptContainerBox.Add(scriptSpaceAtom.CreateBox(environment));
// Adjust shift-up amount.
double p;
if (style == TexStyle.Display)
{
p = texFont.GetSup1(style);
}
else if (environment.GetCrampedStyle().Style == style)
{
p = texFont.GetSup3(style);
}
else
{
p = texFont.GetSup2(style);
}
shiftUp = Math.Max(Math.Max(shiftUp, p), superscriptBox.Depth + Math.Abs(texFont.GetXHeight(
style, lastFontId)) / 4);
}
if (SubscriptAtom != null)
{
// Create box for subscript atom.
subscriptBox = SubscriptAtom.CreateBox(subscriptStyle);
subscriptContainerBox = new HorizontalBox(subscriptBox);
// Add box for script space.
subscriptContainerBox.Add(scriptSpaceAtom.CreateBox(environment));
}
// Check if only superscript is set.
if (subscriptBox is null)
{
superscriptContainerBox.Shift = -shiftUp;
resultBox.Add(superscriptContainerBox);
return(resultBox);
}
// Check if only subscript is set.
if (superscriptBox is null)
{
subscriptBox.Shift = Math.Max(Math.Max(shiftDown, texFont.GetSub1(style)), subscriptBox.Height - 4 *
Math.Abs(texFont.GetXHeight(style, lastFontId)) / 5);
resultBox.Add(subscriptContainerBox);
return(resultBox);
}
// Adjust shift-down amount.
shiftDown = Math.Max(shiftDown, texFont.GetSub2(style));
// Reposition both subscript and superscript.
var defaultLineThickness = texFont.GetDefaultLineThickness(style);
// Space between subscript and superscript.
var scriptsInterSpace = shiftUp - superscriptBox.Depth + shiftDown - subscriptBox.Height;
if (scriptsInterSpace < 4 * defaultLineThickness)
{
shiftUp += 4 * defaultLineThickness - scriptsInterSpace;
// Position bottom of superscript at least 4/5 of X-height above baseline.
var psi = 0.8 * Math.Abs(texFont.GetXHeight(style, lastFontId)) - (shiftUp - superscriptBox.Depth);
if (psi > 0)
{
shiftUp += psi;
shiftDown -= psi;
}
}
scriptsInterSpace = shiftUp - superscriptBox.Depth + shiftDown - subscriptBox.Height;
// Create box containing both superscript and subscript.
var scriptsBox = new VerticalBox();
superscriptContainerBox.Shift = delta;
scriptsBox.Add(superscriptContainerBox);
scriptsBox.Add(new StrutBox(0, scriptsInterSpace, 0, 0));
scriptsBox.Add(subscriptContainerBox);
scriptsBox.Height = shiftUp + superscriptBox.Height;
scriptsBox.Depth = shiftDown + subscriptBox.Depth;
resultBox.Add(scriptsBox);
return(resultBox);
}
public override Box CreateBox(TexEnvironment environment)
{
var texFont = environment.TexFont;
var style = environment.Style;
if ((UseVerticalLimits.HasValue && !UseVerticalLimits.Value) ||
(!UseVerticalLimits.HasValue && style >= TexStyle.Text))
{
// Attach atoms for limits as scripts.
return(new ScriptsAtom(BaseAtom, LowerLimitAtom, UpperLimitAtom).CreateBox(environment));
}
// Create box for base atom.
Box baseBox;
double delta;
if ((BaseAtom as SymbolAtom)?.Type == TexAtomType.BigOperator)
{
// Find character of best scale for operator symbol.
var opChar = texFont.GetCharInfo(((SymbolAtom)BaseAtom).Name, style);
if (style < TexStyle.Text && texFont.HasNextLarger(opChar))
{
opChar = texFont.GetNextLargerCharInfo(opChar, style);
}
var charBox = new CharBox(environment, opChar);
charBox.Shift = -(charBox.Height + charBox.Depth) / 2 -
environment.TexFont.GetAxisHeight(environment.Style);
baseBox = new HorizontalBox(charBox);
delta = opChar.Metrics.Italic;
if (delta > TexUtilities.FloatPrecision)
{
baseBox.Add(new StrutBox(delta, 0, 0, 0));
}
}
else
{
baseBox = new HorizontalBox(BaseAtom?.CreateBox(environment) ?? StrutBox.Empty);
delta = 0;
}
// Create boxes for upper and lower limits.
var upperLimitBox = UpperLimitAtom?.CreateBox(environment.GetSuperscriptStyle());
var lowerLimitBox = LowerLimitAtom?.CreateBox(environment.GetSubscriptStyle());
// Make all component boxes equally wide.
var maxWidth = Math.Max(Math.Max(baseBox.Width, upperLimitBox?.Width ?? 0),
lowerLimitBox?.Width ?? 0);
baseBox = ChangeWidth(baseBox, maxWidth);
if (upperLimitBox != null)
{
upperLimitBox = ChangeWidth(upperLimitBox, maxWidth);
}
if (lowerLimitBox != null)
{
lowerLimitBox = ChangeWidth(lowerLimitBox, maxWidth);
}
var resultBox = new VerticalBox();
var opSpacing5 = texFont.GetBigOpSpacing5(style);
var kern = 0d;
// Create and add box for upper limit.
if (UpperLimitAtom != null)
{
resultBox.Add(new StrutBox(0, opSpacing5, 0, 0));
Debug.Assert(upperLimitBox != null, "upperLimitBox != null");
upperLimitBox.Shift = delta / 2;
resultBox.Add(upperLimitBox);
kern = Math.Max(texFont.GetBigOpSpacing1(style), texFont.GetBigOpSpacing3(style) -
upperLimitBox.Depth);
resultBox.Add(new StrutBox(0, kern, 0, 0));
}
// Add box for base atom.
resultBox.Add(baseBox);
// Create and add box for lower limit.
if (LowerLimitAtom != null)
{
Debug.Assert(lowerLimitBox != null, "lowerLimitBox != null");
resultBox.Add(new StrutBox(0, Math.Max(texFont.GetBigOpSpacing2(style), texFont.GetBigOpSpacing4(style) -
lowerLimitBox.Height), 0, 0));
lowerLimitBox.Shift = -delta / 2;
resultBox.Add(lowerLimitBox);
resultBox.Add(new StrutBox(0, opSpacing5, 0, 0));
}
// Adjust height and depth of result box.
var baseBoxHeight = baseBox.Height;
var totalHeight = resultBox.Height + resultBox.Depth;
if (upperLimitBox != null)
{
baseBoxHeight += opSpacing5 + kern + upperLimitBox.Height + upperLimitBox.Depth;
}
resultBox.Height = baseBoxHeight;
resultBox.Depth = totalHeight - baseBoxHeight;
return(resultBox);
}