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Re: Arc Adjustment proposal


On 10/07/2019 19:25, Seth Hillbrand wrote:
> Proposed solution: I would like to adjust the pcbnew file format and
> internal SHAPE_ARC, DRAWSEGMENT arc and EDGE_MODULE arc to use a single
> format consisting of start point, mid point and end point.  Mid point
> here is defined as the point along the arc that is at the half-angle of
> the full arc.

Hi Seth,

As I've been working on the Constraint Solver for a while, I'd like to
add my 5 cents too. The solver allows to define arcs in different ways:
- center/angles/radius
- start/end point (tangential to adjacent lines/arcs)

The input parameters to the CS is some subset of the above. The outputs
are start/end/midpoint, which define the geometry of an arc for other
processes (plotting/drawing/etc.). In order to derive the arc from its
definition based radius/angles, I need that radius and angles to be
stored in the file too - for example calculating the radius back and
forth from endpoints/midpoint would accumulate rounding errors.

What would you say about storing the start/end/midpoint and the set of
CS arc input parameters which have been specified by the user?


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