[RESOLVED] Semitransparent graphic objects

In a picturebox I have a number of geometric figures, basically rectangles and one polygon creted by means of the Polygon, CreatePolygonRgn and Rectangle functions. The polygon may overlap the rectangles and I would like to plot it semitransparent where the overlapping region occurs. I thought of plotting the rectangles in an invisible picturebox, the polygon in another and then Alphablending them to a visible picturebox. But I wonder if this is appropriate as it would blend the background as well as the polygon.

Any other way to do it?

Make the background white if that is what you are referring to

I finally used the API function SetROP2 with the R2_MASKPEN parameter and this produced a very reasonable effect, much more straightforward than the Alphablend alternative.