Does the polygon tool allow you to edit zones on non-copper layers or
were zones on non-copper layers saved as polygons? If the latter is
the case then I'm guessing this change is not significant but if that
is not the case then there could be some editing issues.
Zones on non copper layers were saved as zones:
(zone (net 0) (net_name "") (layer F.Mask) (tstamp 0) (hatch edge 0.508)
(connect_pads (clearance 0.25))
(min_thickness 0.254)
(fill yes (arc_segments 16) (thermal_gap 0.508)
(thermal_bridge_width 0.508))
...
)
While polygons are saved as gr_poly:
(gr_poly (pts (xy 161.19 92.85) (xy 161.19 98.63) (xy 168.14 98.63) (xy
168.14 93.32)) (layer F.Cu) (width 0.15))
Note that there are nice features in zones like corner smoothing, fill
mode, priority, etc, which could be easily added to zones on non copper
layers, while graphic polygons are simple objects and do not have these
features.
Andrzej
