gSDK->ConvertToPolygonN() does not preserve the original

[Richard1 0]

This function does not return nil on failure (VW2019 SP5.3), instead it seems to be returning the original object.

 

Worse, I have not been able to find any documentation as to which object types are supported by the function.

 

So far I have found that passing it a kLine2D returns the original object, thus the following snippet destroys the original drawing:

MCObjectHandle tempPoly = gSDK->ConvertToPolygonN(h, (Boolean) true, 512);
DoSomethingWithAPolygon"d(tempPoly);

if (tempPoly)
{
  gSDK->DeleteObjectNoNotify(tempPoly);
}

Fortunately this causes our plugin to crash, so our users have not lost data (yet)

[Stefan Bender 3]

Maybe you can check if h == tempPoly to avoid these crashes.

[Stefan Bender 3]

IIrc we are using the old function (without N) in our code. I think it works fine for polylines, rectangles and arcs. I don't know if we are passing other object types. I'm not sure if it is possible to create polygons with less than 3 vertices.