Layer Curve in Globe not visible if area of surrounding SLIs is too small.

I considered farfield with data read in. The layer 'Curve' does not appear in the Geographical distribution. For other tab_name, I tested barents the layer 'Curve' appears. Could be solved..

it seems to be related to the case that for some curves there is only one location. Then, the feature cannot presented, and, so it disappears. The same holds for tab and tab_name

This I moved to feature, which does not depend on the actual globe. It would mean, to use a further implementation, e.g. a minimum circle in the center of the curve for representing the fit and location of a curve. This can have the size of an SLI or better being slightly larger. If area of the curve is larger than the circle, it should not be shown

I assigned this, as this would be nice to have. There exist curves with only one location. Accordingly the fit cannot be highlighted at the moment (call it bug or flaw). May be there is a function to determine the area in the projected coordinates, or similar to be larger than that of an SLI cyrcle. Otherwise a square, the size of a cyrcle, with thin lines is plotted.