kicad-developers team mailing list archive

["lounyov" <lounyov@...>]

--- In kicad-devel@xxxxxxxxxxxxxxx, jean-pierre charras
<jean-pierre.charras@...> wrote:

> > More importantly, how is the zone support going?
> >   
> I am thinking about this, but i have currently no precise idea on this, 
> only questions.
...
> The gerber files use filled polygons, with no holes (like Geoff said, 
> polygons with holes must not used in gerber)
> When a polygon has a hole, it is drawn as 2 (or more) adjacent sub 
> polygons with no hole ( the adjacent edges
> are around the hole)

Hi. What if all polygons will be represented as a set of triangles?
In order to fill a polygon along the filling proccess we need to
perform a check operation (check if a point is inside of the polygon
or not). There is no universal rule to do this check. In case of an
arbitrary polygon it is necessary to split it into convex polygons or
in the simplest case into triangles. After that a simple rule can be
used to check if a point is inside of triangle or not. If given point
is inside of at least one triangle then the point is inside of the
polygon to be filled.
This check operation can be used also for all cutout polygons such as
cutouts, pads, vias, traces and other polygons not belonged to the net
name which the polygon to be filled is connected.
Also to form gerber files the triangles can be used instead of
multiple concave polygons (as said polygons with holes must not used
in gerber).
Thus I think it is reasonable to represent polygons as a set of triangles.

Alexander Lunev