Beta Release of ezdxf v1.2.0b2

[mozman]

Updated Changelog in the Knowledge Graph...

The last missing part for the v1.2 release was added - concave clipping polygons. But there are some bugs to fix until the final release:

EDIT: The current implementation of the concave clipping polygon is pure Python and therefore very slow. A faster Cython implementation will be added after the v1.2 release.

[mozman]

Clipping of block references (XCLIP) seems to work:

regular clipping paths: rectangle, convex, concave

and inverted clipping paths:

I will do one additional beta release v1.2.0b3 before the final release.