Cairo supports antialiasing when rendering but can be slow when set to
sub-pixel mode. This bumps the minimum version of Cairo to 1.12
(available in 14.04 LTS as well as mingw) to support three antialias
settings (fast, good, best) that offer speed/appearance tradeoffs.
This can provide a higher-quality eeschema render as it works on a
per-element basis as opposed to the OpenGL per-screen antialias.
The motivation here is to concentrate display options in the GAL display
settings, ready for removal of legacy canvases. Instead of having the
property as a member of the DRAW_FRAME, with the GAL canvas retreiving
it from there, it is now in the GAL_DISPLAY_OPTIONS struct, and both GAL
and legacy get it from there.
The options for setting cursor shape are then moved out of the general
options dialog, and into the GAL display options widget, where they can
be used in all GAL-aware programs.
GAL cursor shape works on GAL, but not legacy, so the option is now
available on OSX (but only affects GAL, and is labelled as such).
A new items is added to the GAL display options (and the dialog), and a
hotkey (Ctrl+Shift+x) is added to toggle it.
Fixes: lp:1673633
* https://bugs.launchpad.net/kicad/+bug/1673633
When reading config options from files, it's important to make sure the
value makes sense - the incoming data could be anything, and may have
incompatible values or be otherwise unreliable.
This introduces a simple way to define and use "mapping tables" which
can map between a "native" value, probably an enum (but not necessarily)
and some external value, for example the value written to file.
This provides a decoupling between the two values, as well as sanitising
inputs and outputs. This is important, as over time, if there isn't a
decoupled interface, changing options result in corrupt configs, or a
proliferation of obsolete enum values kept for compatibility.
GAL_DISPLAY_OPTIONS_OBSERVER aren't deleted by a base class pointer -
they are an "incidental" part of other classes. Add a virtual protected
destructor to make this explicit.
This allows the user to set a thicker grid line without causing the
grid lines to become over dense, or just make the grid denser according
to preference.
The term "density" is modified to "minimum grid spacing", which is
the pixel spacing between adjacent grid lines.
The spacing settings now comes in along, with other GAL display settings,
as part of GAL_DISPLAY_OPTIONS observer functionality. To this end, the
setter in GAL interface is removed, as an external user should be
setting this parameter via the GAL_DISPLAY_OPTIONS interface.
This adds a user-settable control for the grid line thickness on GAL
canvases to the display options dialog.
The thickness settings now comes in, along with other GAL display
settings, as part of GAL_DISPLAY_OPTIONS observer functionality. To this
end, the setter in GAL interface is removed, as an external user should
be setting this parameter via the GAL_DISPLAY_OPTIONS interface.
Fixes: lp:1662482
* https://bugs.launchpad.net/kicad/+bug/1662482
This puts the graphical/display options with the other similar options
in that dialog, rather than with the dimension options found in the Set
Grid dialog, which is in the Dimensions menu.
Also place the option itself in the GAL Display Options structure, so it
can be updated using the observer mechanism there.
The setter for the style in the GAL interface is removed, as the public
interface for setting this option is now to modify the
GAL_DISPLAY_OPTIONS structure and notify the GAL when done.