Wayland prototype for rendering software that runs remotely
Source: YouTube screenshot
Wayland chief developer Kristian Høgsberg has presented an extension for the Weston compositor for Wayland that allows a local version of Weston to display individual windows of a Weston instance that is running on another system. Within the Wayland display server architecture, such tasks are handled by the compositor, which functions as a display server because Wayland itself offers no rendering API and mainly focuses on bitmap rendering features. Therefore, the remote display solution for Weston doesn't require any remote drawing commands to be transferred through the network; instead, the system transmits complete images together with any updated image areas, and the local Weston simply displays them.
Wayland, the potential X11 successor, has been criticised for its lack of network transparency – many users appreciate this functionality in X11. Høgsberg presented the Weston prototype for rendering windows via a network at the X.Org Developer Conference last week. A presentation video is available: explanations and a demonstration that is accompanied by a crash of Weston begin at time stamp 1:11:50.
In his presentation, Høgsberg also provides a short overview of the Wayland architecture and explains how video output is accelerated in Wayland. The developer presents the current development status of Xwayland, a technology that allows X11 applications to be executed in a Wayland compositor such as Weston; parts of this description can be found in the video of the third part of the presentation.
Høgsberg has once again confirmed that Wayland 1.0 is scheduled to arrive in the coming weeks. However, with this release, the Wayland ecosystem will not yet be mature enough to replace X11 in mainstream distributions. Version 1.0 is mainly intended as a point from which the programming interfaces will no longer be modified in incompatible ways, which will provide a stable basis for the developers of compositors and graphics libraries such as EFL, GTK+ and Qt.
The current versions 0.95 of Wayland and Weston can already be manually installed through the package repositories in the pre-release versions of Fedora 18 and Ubuntu 12.10. In a recent blog post, the developer of the KDE desktop's KWin Compositing Window Manager explained which measures are still required before KDE can work as a Wayland client and KWin as a Wayland compositor. However, no timeframe has so far been established for this, because the switch to Wayland will only be made once KDE has been ported to the soon-to-be-released Qt5 toolkit that supports Wayland.
The X.Org Developer Conference also discussed many other important graphics rendering aspects for Linux systems – including some thoughts on a Direct Rendering Infrastructure 3 (DRI3) that could replace the current DRI2. Details of this can be found in the conference proceedings that link to video recordings of many presentations and discussions. According to this page, X.org's X Server 1.14 is scheduled to be released on 5 March, 2013, and is expected to offer a new DRI version, possibly Xwayland, and an atomic mode-setting feature for screen resolutions with KMS.
- Conference videos on GStreamer, 3D drivers and Wayland, a report from The H.