LayoutRect RenderMathMLOperator::paintCharacter(PaintInfo& info, UChar character, const LayoutPoint& origin, CharacterPaintTrimming trim)
{
GlyphData data = style()->font().glyphDataForCharacter(character, false);
FloatRect glyphBounds = data.fontData->boundsForGlyph(data.glyph);
LayoutRect glyphPaintRect(origin, LayoutSize(glyphBounds.x() + glyphBounds.width(), glyphBounds.height()));
glyphPaintRect.setY(origin.y() + glyphBounds.y());
// In order to have glyphs fit snugly with one another we snap the connecting edges to pixel boundaries
// and trim off one pixel. The pixel trim is to account for fonts that have edge pixels that have less
// than full coverage. These edge pixels can introduce small seams between connected glyphs
FloatRect clipBounds = info.rect;
switch (trim) {
case TrimTop:
glyphPaintRect.shiftYEdgeTo(glyphPaintRect.y().ceil() + 1);
clipBounds.shiftYEdgeTo(glyphPaintRect.y());
break;
case TrimBottom:
glyphPaintRect.shiftMaxYEdgeTo(glyphPaintRect.maxY().floor() - 1);
clipBounds.shiftMaxYEdgeTo(glyphPaintRect.maxY());
break;
case TrimTopAndBottom:
LayoutUnit temp = glyphPaintRect.y() + 1;
glyphPaintRect.shiftYEdgeTo(temp.ceil());
glyphPaintRect.shiftMaxYEdgeTo(glyphPaintRect.maxY().floor() - 1);
clipBounds.shiftYEdgeTo(glyphPaintRect.y());
clipBounds.shiftMaxYEdgeTo(glyphPaintRect.maxY());
break;
}
// Clipping the enclosing IntRect avoids any potential issues at joined edges.
GraphicsContextStateSaver stateSaver(*info.context);
info.context->clip(clipBounds);
info.context->drawText(style()->font(), TextRun(&character, 1), origin);
return glyphPaintRect;
}
