Public Member Functions |
virtual | ~QwtTextEngine () |
virtual void | draw (QPainter *painter, const QRectF &rect, int flags, const QString &text) const =0 |
virtual double | heightForWidth (const QFont &font, int flags, const QString &text, double width) const =0 |
virtual bool | mightRender (const QString &text) const =0 |
virtual void | textMargins (const QFont &font, const QString &text, double &left, double &right, double &top, double &bottom) const =0 |
virtual QSizeF | textSize (const QFont &font, int flags, const QString &text) const =0 |
Abstract base class for rendering text strings.
A text engine is responsible for rendering texts for a specific text format. They are used by QwtText to render a text.
QwtPlainTextEngine and QwtRichTextEngine are part of the Qwt library. The implementation of QwtMathMLTextEngine uses code from the Qt solution package. Because of license implications it is built into a separate library.
- See also:
- QwtText::setTextEngine()
virtual void QwtTextEngine::textMargins |
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const QFont & |
font, |
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const QString & |
text, |
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double & |
left, |
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double & |
right, |
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double & |
top, |
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double & |
bottom |
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pure virtual |
Return margins around the texts
The textSize might include margins around the text, like QFontMetrics::descent. In situations where texts need to be aligend in detail, knowing these margins might improve the layout calculations.
- Parameters:
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font | Font of the text |
text | Text to be rendered |
left | Return value for the left margin |
right | Return value for the right margin |
top | Return value for the top margin |
bottom | Return value for the bottom margin |
Implemented in QwtRichTextEngine, QwtPlainTextEngine, and QwtMathMLTextEngine.