[SOLVED]how to update the polygon point of a custom QGraphicsPolygonItem?

[opengpu]

i want to update the polygon point of a custom QGraphicsPolygonItem, i got the point from the m_Polygon, and change its value, then i use the API setPolygon() again...
my it's the same m_Polygon, and i just changed some point value in it, and is there any update() kinda API to do this?

[Asperamanca]

You changed a copy of the polygon. You need to set the polygon for the update to happen. If you need anything else, you will have to write a custom GraphicsItem.

[opengpu]

so there is no way except call setPolygon() again?
i just want to know if it is the most effcient way.

[Asperamanca]

There is no other way I know of. If you want more efficiency, you would probably have to write your own specialized item.

[opengpu]

ok thanks very much