As I understand it, QCustomPlot uses QPixmaps as a cache. This is necessary in order not to redraw the entire "scene", when the state of the "scene" has not changed, but is called by paintEvent.

But for some reasons (one of thems - QPixmap on widget 1920x1080 have size 1920*1080*8 = 15.8Mb - it is a lot for my situation) , I need to draw directly to the widget . If it is possible, how can this be done?