How i can plot result in my GUI ?

[FelixB]

yes, you have to call "setsamples" - after the loop. during the loop, you have to fill the QPolygonF with points.

this is simple c++, so I won't give you code. You'll learn more by finding the solution by yourself to give you some hints: you need *one* QPolygonF, not 10. You want, that this QPOlygonF contains 10 QPoints. You want to plot these 10 points=one polygon...