Self interacting splines

[Anonymous]

Hello to everybody,

I am having some issues while moddeling a sal with splines, its giving the error that I indicated in the title, as you can see in the picture above.

[L.Maas]

So the error gives the reason it is not accepting the shape. So you would need to (re)model it that it is not self-intersecting.

For this you might need greater angles or profiles with smaller diameters. Or you might need to remodel it in a different way with different (e.g extrusion instead of sweeps). Another solution might be to make by create multiple objects

[Anonymous]

So, basically you are saying that somewhere in my drawing the splines are interacting or in other words overlapping? that what I understood by what you said. Sorry for my ignorance I am just recently learning the program.

[charles.roucher]

I am afraid you have met one of the many limitations of Revit. 
The typical error "Self intersecting splines are not allowed in sketches" appear even when I am not using splines. So the issue is not the spline, the issue is Revit cannot deal with curvature. I was trying to create a pad so to cut our Topography where our buildings are. The outline of our Buildings have elliptical curves. I add to replace all the curved lines with straight lines, that's the only way Revit could have it to work.

So it is pretty pathetic from Revit but not surprising because this is probably why you rarely use Revit in 3D and always have to define your reference planes and create views in order to modify the model. To do it straight out of a 3D view is doable but Revit is a pig to even snap. Archicad is a proper 3D modeler, you want to connect two points, no problem the line between is smart enough to offer you options whether it has to be parallel to the ground or not. The fact that Revit cannot even snap a curved line with a straight line even though it tricks you to think it can (via the little pink square that normally indicate a successful snap) is quite disconcerting. 
So try replacing your curved line with a straight line to see if it works, then maybe facet your corner to simulate a curve. It is a waste of time but that's Revit for you.