Only integers from QFontMetricsF width

[StevenB]

I'm getting only integer values from QFontMetricsF::width() and QFontMetricsF.boundingRect().width().
I'm trying to use the width to draw a box with GraphicsView, but because of the integer coordinates, the box sometimes overlaps the text.

Here's the code I'm using:

QFont font("Sans", 12);
font.setPointSizeF(13.2524);
fontsizer = new QFontMetricsF(font);
std::cout << "width: " << fontsizer->width("string") << std::endl;

QFont font("Sans", 12);
font.setPointSizeF(13.2524);
fontsizer = new QFontMetricsF(font);
std::cout << "width: " << fontsizer->width("string") << std::endl;

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Am I doing something wrong?