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Re: Arc Adjustment proposal


Hi Tom-

On 2019-07-11 08:52, Tomasz Wlostowski wrote:
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?

I prefer to avoid extra parameters if we can as it makes editing by hand much harder. But if we need them, I'm not opposed. I'm not certain, however, how we keep the parameter relation under affine transformation as someone needs to drive the other. It feels like we lose the relation during computation and not during storage. What am I missing?