This fixes some DXFs imports where unforunately CAD tools like SolidWorks
randomly decide to mirror circle definitions across the "z" axis (resulting in x or y axis flips in 2d)
Most likely live projection from 3D to 2D drawings introduces this.
However this is DXF specification to describe it so obtusely with vectors for a 2d drawing.
DXF blocks are virtual groups of items.
The insert entity is what actually places all the block contents at a given coordinate.
This should fix importing drawings from professional CAD tools like SolidWorks that will have a good bit of blocks.
The reality is the DXF file can still override the selected unit option which is totally fine.
In fact, per specification, there is a way to change units mid-file with block records :/
There is no guarantee DXF contains $INSUNIT to specify the units of the file as its optional.
This allows the user to specify the expected units via dropdown.
SolidWorks can definitely generate such unit lacking files as an example
ADDED: Allow DXF/SVG graphics to be imported as a group
Also, cleanup the placement routine to allow the edit tool's flip
and rotate routines to be used when placing the items.
CHANGED: Settings are now stored in versioned sub-directories
ADDED: First-run dialog for migrating settings from a previous version
CHANGED: Settings are now stored as JSON files instead of wxConfig-style INI files
CHANGED: Color settings are now all stored in a separate settings file
CHANGED: The symbol editor and footprint editor now have their own settings files
CHANGED: Color settings are no longer exposed through BOARD object
CHANGED: Page layout editor now uses Eeschema's color scheme
Settings are now managed through a central SETTINGS_MANAGER held by PGM_BASE.
Existing settings will be migrated from the wxConfig format on first run of each application.
Per-application settings are now stored in one class for each application.
Sometimes a dxf curve is a "degenerated" bezier curve having only 3 points.
(a control point is at same location as a end point)
This commit fix incorrect import of these curves.
Marek Roszko
Michael Kavanagh
Jeff Young
Wayne Stambaugh
Ian McInerney
jean-pierre charras
Jon Evans