Make the evaluation faster, by only checking the formula in the border of the object

[dieuska]

When having bigger objects the brdr_formula becomes quite big, so a lot has to be checked;

Also inner changes can occur while they do not effect the evaluation.

So:

• only the reference polygons in a outer circle can be checked and compared?
• Or only compare the reference_objects that are not full?
• ...

[dieuska]

possibility to only check borders for grb-parcels already possible. To check if we have to expand this

[dieuska]

for example when comparing the brdr_formula we could only check the border-part of the formula:

• big polygons: If 'outer ring' has same formula (do net check inner side) --> automatic update
  ** outer ring can be calculated: 1) negative buffer 2) original - buffered