Copyright 2016 The Chromium Authors. 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. This protocol specifies a set of interfaces used to control the alpha compositing and blending of contents. Warning! The protocol described in this file is experimental and backward incompatible changes may be made. Backward compatible changes may be added together with the corresponding interface version bump. Backward incompatible changes are done by bumping the version number in the protocol and interface names and resetting the interface version. Once the protocol is to be declared stable, the 'z' prefix and the version number in the protocol and interface names are removed and the interface version number is reset. The global interface exposing compositing and blending capabilities is used to instantiate an interface extension for a wl_surface object. This extended interface will then allow the client to specify the blending equation and alpha value used for compositing the wl_surface. Informs the server that the client will not be using this protocol object anymore. This does not affect any other objects, blending objects included. Instantiate an interface extension for the given wl_surface to provide surface blending. If the given wl_surface already has a blending object associated, the blending_exists protocol error is raised. An additional interface to a wl_surface object, which allows the client to specify the blending equation used for compositing and an alpha value applied to the whole surface. If the wl_surface associated with the bledning object is destroyed, the blending object becomes inert. If the blending object is destroyed, the blending state is removed from the wl_surface. The change will be applied on the next wl_surface.commit. The associated wl_surface's blending state is removed. The change is applied on the next wl_surface.commit. Blending equations that can be used when compositing a surface. Set the blending equation for compositing the wl_surface. See wp_alpha_compositing for the description. The blending equation state is double-buffered state, and will be applied on the next wl_surface.commit. Set the alpha value applied to the whole surface for compositing. See wp_alpha_compositing for the description. The alpha value state is double-buffered state, and will be applied on the next wl_surface.commit.