Protocol tearing_control_v1

License 
    Copyright © 2021 Xaver Hugl

    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
    to deal in the Software without restriction, including without limitation
    the rights to use, copy, modify, merge, publish, distribute, sublicense,
    and/or sell copies of the Software, and to permit persons to whom the
    Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice (including the next
    paragraph) shall be included in all copies or substantial portions of the
    Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
    DEALINGS IN THE SOFTWARE.

Interface wp_tearing_control_manager_v1 — protocol for tearing control

For some use cases like games or drawing tablets it can make sense to reduce latency by accepting tearing with the use of asynchronous page flips. This global is a factory interface, allowing clients to inform which type of presentation the content of their surfaces is suitable for.

Graphics APIs like EGL or Vulkan, that manage the buffer queue and commits of a wl_surface themselves, are likely to be using this extension internally. If a client is using such an API for a wl_surface, it should not directly use this extension on that surface, to avoid raising a tearing_control_exists protocol error.

Warning! The protocol described in this file is currently in the testing phase. Backward compatible changes may be added together with the corresponding interface version bump. Backward incompatible changes can only be done by creating a new major version of the extension.

Request wp_tearing_control_manager_v1.destroy — destroy tearing control factory object

Destroy this tearing control factory object. Other objects, including wp_tearing_control_v1 objects created by this factory, are not affected by this request.

Request wp_tearing_control_manager_v1.get_tearing_control — extend surface interface for tearing control

Instantiate an interface extension for the given wl_surface to request asynchronous page flips for presentation.

If the given wl_surface already has a wp_tearing_control_v1 object associated, the tearing_control_exists protocol error is raised.

Enum wp_tearing_control_manager_v1.error

  • tearing_control_exists: the surface already has a tearing object associated

Interface wp_tearing_control_v1 — per-surface tearing control interface

An additional interface to a wl_surface object, which allows the client to hint to the compositor if the content on the surface is suitable for presentation with tearing. The default presentation hint is vsync. See presentation_hint for more details.

Request wp_tearing_control_v1.set_presentation_hint — set presentation hint

Set the presentation hint for the associated wl_surface. This state is double-buffered and is applied on the next wl_surface.commit.

The compositor is free to dynamically respect or ignore this hint based on various conditions like hardware capabilities, surface state and user preferences.

  • hint uint: None

Request wp_tearing_control_v1.destroy — destroy tearing control object

Destroy this surface tearing object and revert the presentation hint to vsync. The change will be applied on the next wl_surface.commit.

Enum wp_tearing_control_v1.presentation_hint — presentation hint values

This enum provides information for if submitted frames from the client may be presented with tearing.

  • vsync: tearing-free presentation
  • async: asynchronous presentation