How to rotate text for drawText?
16,660
Solution 1
Insert painter->rotate(45);
before painter->drawText(75, 100 + i * 800/9 - 6, 40, 40, 1, str);
and painter->rotate(-45);
after (to restore the rotation angle of the coordinate system):
painter->rotate(45);
painter->drawText(75, 100 + i * 800/9 - 6, 40, 40, 1, str);
painter->rotate(-45);
Depending on if you mean 45 degrees clockwise or anti-clockwise you may need to negate the rotation angles.
After you rotate the coordinate system, everything you paint will be painted rotated until you restore the painter. A convenient way of saving and restoring the state of the painter is using QPainter::save()
and QPainter::restore()
.
Solution 2
painter->save(); // saves current painter state
// painter->rotate(45); clockwise rotation
// painter->rotate(-45); counter clockwise rotation
painter->restore(); // restores painter state
Solution 3
In order to rotate your text (and any other drawable object) drawn by painter just call
painter->rotate(yourAngle);
before
painter->drawText();
If you wish to return to previous state call rotate again.
painter->rotate(-yourAngle);
Author by
jdl
Updated on June 13, 2022Comments
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jdl almost 2 years
I would like to rotate the text 45 degrees?
QFont font; font.setPixelSize(12); //grid for(int i = 0; i < 10; i++){ painter->drawLine(100, 100 + i * 800/9, 900, 100 + i * 800/9); str = QString::number((double)9 - i, 'd', 1); painter->setFont(font); painter->drawText(75, 100 + i * 800/9 - 6, 40, 40, 1, str); }
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Frank Osterfeld almost 11 yearsEither the rotate(-45) or the save/restore can be omitted
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Admin over 5 yearsBut QPainter.rotate() - rotate coordinate system. So x and y coord in drawText now is incorrect