The x264 project is successful in now producing video compliant with the Blu-ray specification. To rejoice over this support, the x264 project has put out a Blu-ray-encoded disc that -- thanks to the compression abilities of x264 -- can actually fit and be burned onto a standard DVD. This video contains liberally licensed media to illustrate this feat.
What's still missing from the equation though is a Blu-ray authoring tool to add menus, combine audio and video streams, etc. However, the hard part of Blu-ray encoding is now working.
The details surrounding this achievement for the x264 project are discussed in this blog post. At VideoLan.org Git is the commit that introduces this Blu-ray support.
Introduced as part of this support upbringing is full NAL-HRD compliance, full VDR rate control support, pull-down support, and Pic_struct support.