What is a point? whereas pixel is clear enough: it is a physical unit on the screen, the nature of the point in not so explicit.

CodePudding user response：

A point is a measure that equals 1/72 inches. The main difference between pointSize and pixelSize is that pointSize is density independent, which means that the size is physically fixed, whatever screen you use. Highdpi scaling can or can not affect point size, it depends on the setup: https://doc.qt.io/qt-5/highdpi.html.

CodePudding user response：

If I am correct, the point size is based on an abstract layer provided by Qt to do a High DPI scaling.

Please follow: https://doc.qt.io/qt-6/highdpi.html