Set up a new lineage for SCH_ITEMS to get back to the SCHEMATIC
they live on: Items will all be parented to the SCH_SCREEN that
they are added to, and each SCH_SCREEN will point back to the
SCHEMATIC that it is part of. Note that this hierarchy is not
the same as the actual schematic hierarchy, which continues to
be managed through SCH_SHEETs and SCH_SHEET_PATHS.
This is a very large and potentially disruptive change so this will be an
unusually long and detailed commit message.
The new file formats are now the default in both the schematic and symbol
library editors. Existing symbol libraries will be saved in their current
format until new features are added to library symbols. Once this happens,
both the legacy schematic and symbol file formats will be no longer be
savable and existing libraries will have to be converted. Saving to the
legacy file formats is still available for round robin testing and should
not be used for normal editing.
When loading the legacy schematic file, it is imperative that the schematic
library symbols are rescued and/or remapped to valid library identifiers.
Otherwise, there will be no way to link to the original library symbol and
the user will be required manually set the library identifier. The cached
symbol will be saved in the schematic file so the last library symbol in
the cache will still be used but there will be no way to update it from the
original library.
The next save after loading a legacy schematic file will be converted to
the s-expression file format. Schematics with hierarchical sheets will
automatically have all sheet file name extensions changed to .kicad_sym
and saved to the new format as well.
Appending schematics requires that the schematic to append has already been
converted to the new file format. This is required to ensure that library
symbols are guaranteed to be valid for the appended schematic.
The schematic symbol library symbol link resolution has been moved out of
the SCH_COMPONENT object and move into the SCH_SCREEN object that owns the
symbol. This was done to ensure that there is a single place where the
library symbol links get resolved rather than the dozen or so different
code paths that previously existed. It also removes the necessity of the
SCH_COMPONENT object of requiring any knowledge of the symbol library table
and/or the cache library.
When opening an s-expression schematic, the legacy cache library is not
loaded so any library symbols not rescued cannot be loaded. Broken library
symbol links will have to be manually resolved by adding the cache library
to the symbol library table and changing the links in the schematic symbol.
Now that the library symbols are embedded in the schematic file, the
SCH_SCREEN object maintains the list of library symbols for the schematic
automatically. No external manipulation of this library cache should ever
occur.
ADDED: S-expression schematic and symbol library file formats.
Don't clobber value file when load aliases in legacy symbol library cache
parser.
Use actual symbol library LIB_PART pointer rather than a flattened copy
of the symbol. This fixed a bug when displaying the parent field in the
message panel for derived symbols.
Simplify the flatten code by copying the parent and updating the lesser
information from the inherited symbol.
This change completely removes the LIB_ALIAS design pattern an replaces
it by allowing LIB_PART objects to inherit from other LIB_PART objects.
The initial implementation only allows for single inheritance and only
supports the mandatory fields in the derived part because that is all
that the current symbol library file format will support. Once the new
file format is implemented and saving to the old file format is deprecated,
more complex inheritance will be added. The LIB_ALIAS information saved
in the document files was move into the LIB_PART object. This change
impacts virtually every part of the schematic and symbol library editor
code so this commit message is woefully incomplete.
REMOVE: Removed the symbol aliases concept from the schematic and symbol
editors and the symbol viewer.
NEW: Replace the symbol alias concept with simple inheritance that allows
a library symbol to be derived from another library symbol.
It's a bit of a hack because they're statically initialized and
so we can't make use of the _() macro. We do still want it in the
code, however, because the string harvesting is based off of it.
Fixes: lp:1833000
* https://bugs.launchpad.net/kicad/+bug/1833000