KDE output management

This interface enables clients to set properties of output devices for screen configuration purposes via the server. To this end output devices are referenced by global org_kde_kwin_outputdevice objects.

outputmanagement (wl_global) -------------------------- request:

• create_configuration -> outputconfiguration (wl_resource)

outputconfiguration (wl_resource) -------------------------- requests:

• enable(outputdevice, bool)
• mode(outputdevice, mode_id)
• transformation(outputdevice, flag)
• position(outputdevice, x, y)
• apply

events:

• applied
• failed

The server registers one outputmanagement object as a global object. In order to configure outputs a client requests create_configuration, which provides a resource referencing an outputconfiguration for one-time configuration. That way the server knows which requests belong together and can group them by that.

On the outputconfiguration object the client calls for each output whether the output should be enabled, which mode should be set (by referencing the mode from the list of announced modes) and the output's global position. Once all outputs are configured that way, the client calls apply. At that point and not earlier the server should try to apply the configuration. If this succeeds the server emits the applied signal, otherwise the failed signal, such that the configuring client is noticed about the success of its configuration request.

Through this design the interface enables atomic output configuration changes if internally supported by the server.

outputconfiguration is a client-specific resource that can be used to ask the server to apply changes to available output devices.

The client receives a list of output devices from the registry. When it wants to apply new settings, it creates a configuration object from the outputmanagement global, writes changes through this object's enable, scale, transform and mode calls. It then asks the server to apply these settings in an atomic fashion, for example through Linux' DRM interface.

The server signals back whether the new settings have applied successfully or failed to apply. outputdevice objects are updated after the changes have been applied to the hardware and before the server side sends the applied event.