This protocol allows a privileged client to set the gamma tables for
outputs.
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.
manager to create per-output gamma controls
Interface
Version 1
This interface is a manager that allows creating per-output gamma
controls.
get a gamma control for an output
Request
Since Version 1
Create a gamma control that can be used to adjust gamma tables for the
provided output.
Destructor
Request
Since Version 1
All objects created by the manager will still remain valid, until their
appropriate destroy request has been called.
adjust gamma tables for an output
Interface
Version 1
This interface allows a client to adjust gamma tables for a particular
output.
The client will receive the gamma size, and will then be able to set gamma
tables. At any time the compositor can send a failed event indicating that
this object is no longer valid.
There can only be at most one gamma control object per output, which
has exclusive access to this particular output. When the gamma control
object is destroyed, the gamma table is restored to its original value.
Set the gamma table. The file descriptor can be memory-mapped to provide
the raw gamma table, which contains successive gamma ramps for the red,
green and blue channels. Each gamma ramp is an array of 16-byte unsigned
integers which has the same length as the gamma size.
The file descriptor data must have the same length as three times the
gamma size.
| Argument | Type | Description |
|---|
| fd | fd | gamma table file descriptor |
Destructor
Request
Since Version 1
Destroys the gamma control object. If the object is still valid, this
restores the original gamma tables.
Advertise the size of each gamma ramp.
This event is sent immediately when the gamma control object is created.
| Argument | Type | Description |
|---|
| size | uint | number of elements in a ramp |
This event indicates that the gamma control is no longer valid. This
can happen for a number of reasons, including:
- The output doesn't support gamma tables
- Setting the gamma tables failed
- Another client already has exclusive gamma control for this output
- The compositor has transferred gamma control to another client
Upon receiving this event, the client should destroy this object.
| Entry | Value | Since | Description |
|---|
| invalid_gamma | 1 | 1 | invalid gamma tables |
Copyright
Copyright © 2015 Giulio camuffo
Copyright © 2018 Simon Ser
Permission to use, copy, modify, distribute, and sell this
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