When speaking of Qt Widget's performance, we mean the performance; either the graphics performance of their respective software or OpenGL backends, or the performance of often used model/view model. We will start this discussion with performance.
Qt Widget's performance
QPainter
The software rasterizer will be used when painting the regular widgets through the QPainter class. However, QPainter class will never paint directly to the window, but rather uses a QBackingStore object, which will contain a buffered representation of the window contents. This enables Qt to implement partial updates by using QPainter only to update a subregion of the window. QBackingStore contents will be finally flushed, that is, written...
