This adds a richer overlay to the arc-by-three-points tool in Pcbnew,
including more guide-lines and a live display of radius and angle.
Also included is ability to go back to the previous step (if setting end
angle, you can go back to setting start point, etc) using Backspace, and
Ctrl snaps the start/end angles to 45 degree multiples.
This adds new classes
* MULTISTEP_GEOM_MANAGER: represents a generic "geometry manager" that
builds up some geometrical construction based on a sequence of points.
Used by:
* ARC_GEOM_MANAGER: handles the logical flow of constructing an
arc by centre-point, set radius, set angle. This moves the logic out
of the Pcbnew DRAWING_TOOL event loop in drawArc().
* ARC_ASSISTANT: graphical overlay to communicate current arc shape to
the user during the drawing process
This allows to measure between features on a PCB. It uses a preview
EDA_ITEM in common, but due to the use of the IDs, it's currently
Pcbnew/Modedit only.
This also adds several "utils" for graphical functons useful when
drawing preview items on GAL canvases.
Fixes: lp:1467313
* https://bugs.launchpad.net/kicad/+bug/1467313
This simplifies the (already simple) SELECTION_AREA class. It is also
moved into KIGFX::PREVIEW and put in the common library, where it can be
reused by other GAL-aware tools (not just in Pcbnew) in future.
This introduces SIMPLE_OVERLAT_ITEM, which is an abstract EDA_ITEM,
designed for use as an overlay for assisting interactive tools.
The item is drawn only on the GP_OVERLAY layer, and sets the fill,
stroke and line properties before calling a virtual function to draw the
shape, which will depend on the implementaiton of the derived class.
The motivation here is to simplify and unify basic overlays used when
in interactive tools. It is not designed to be the base class of all
possible overlays - more complex ones would be more clearly represented
as their own derivative of EDA_ITEM.
Applications of this class can include: zoom/select rectangles, zone
polygon previews, geometric shape helpers, and so on.