GNOME's Mutter Now Supports GBM With Modifiers - Allowing Tiling & Compression

Landing today in GNOME's Mutter Git tree are some longstanding patches by Collabora's Daniel Stone for supporting the Generic Buffer Manager (GBM) with buffer modifiers for DRM.

By Mutter supporting buffer modifiers when its serving as a Wayland compositor, it can now support tiling and compression of scanout surfaces when passing to the DRM drivers via Mesa's GBM.

With compressed surfaces, a significant benefit is the video memory bandwidth savings. This support though depends upon kernel additions found in Linux 4.14 and newer.

Daniel Stone has been working on this support for Mutter since last summer while merged today was support for the modifier-aware GBM API, creating GBM surfaces with modifiers, and using the new IN_FORMATS property added to Linux 4.14.

This Mutter usage of buffer modifiers will be present in GNOME 3.28 due out this March.