Editable arc radius and starting angle

[reguspregus]

It would be very useful to have an ability to edit arc radius and starting angle.

When arc is being created, user specifies the following parameters:

1. center point
2. radius
3. absolute starting angle
4. relative ending angle

However, when editing existing arc, the only editable parameters are:

1. center point,
2. starting point
3. relative ending angle

It would be great if Properties dialog had an option for switching between two sets of parameters as listed above for editing purposes. Depending on which set is active, the other one would be automatically recomputed.

There are two reasons for request:

1. It makes sense to have consistent set of parameters between creation and editing
2. Many edits are parametric in nature and angles and radii are frequently used for such edits

[BobZ]

I do not claim to be a power user… Sometimes I see that a question has no response and I try to help get the ball rolling more than expect to give a great answer…

1. What version of KiCad are you using? See help>about>copy version info?
2. Typically what are you trying to draw when you are drawing these arcs? Footprints? Symbols? Board outline?

I can see where the flexibility you describe makes sense. There are many aspects of KiCad which are less than ideal but that observation by no means puts it at the bottom of the pile (so to speak.)

[John_Pateman]

KiCad has never really claimed to be a fully featured, constrained design environment although recent features have improved this area. The general advice is to use a design program if you need more complex layouts and import a dxf into the appropriate layer.

[TimC_Harris]

I agree with @reguspregus that editing arcs is a bit fiddly. I quite often found myself typing in (trial and error) four decimal points of a degree to aim for the arc I intend.
I would like to offer a third view.
My target is to produce a pcb. The KiCad tools get me all the way from the concept to a set of Gerber files. So if we consider the Gerber concept of an arc, the angles are not a parameter at all. They rely on:

1. Start Point
2. Centre Point
3. End Point
4. an explicit instruction of clockwise of anticlockwise path from start to end.

Ucamco’s recent specification [Revision 2021.04] is honest enough to point out the ‘fuzziness’ of this description. But while we are using Gerbers I would like any dialog that allows me to edit arcs to show me calculations of these fundamental four measures if I edit the other features such as start and ending angles. Or show me angles if I edit start, end and centre points.

But, as @BobZ says, this is not likely to be a feature at the top of the pile for development.