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.
Factor out save current canvas view to image file code from symbol editor
code so it can be used anywhere.
Add ability to save to any image format supported by wxBitmapType. See
https://docs.wxwidgets.org/3.0/gdicmn_8h.html#a90a1eb6d85b5044a99b706fd979f27f5.
Currently only PNG output is implemented.
Please note that there is a minor bug that appears to be due to the
scroll bars which causes unfilled areas on the right and bottom edges
of the image. This always existed in the save symbol editor view
image but it was not as noticeable because by default the background
color is white. It is very noticeable in the footprint editor with
a black background.
The usual smattering of coding policy and comment fixes.
Fixes lp:1802127
https://bugs.launchpad.net/kicad/+bug/1802127
Jeff Young
Wayne Stambaugh
jean-pierre charras
Tomasz Wlostowski