WlDisplayBase

Represents a connection to the compositor and acts as a proxy to the wl_display singleton object.

A WlDisplay object represents a client connection to a Wayland compositor. It is created with either WlDisplay.connect() or WlDisplay.connect_to_fd(). A connection is terminated using disconnect().

A WlDisplay is also used as the WlProxy for the wl_display singleton object on the compositor side.

A WlDisplay object handles all the data sent from and to the compositor. When a WlProxy marshals a request, it will write its wire representation to the display's write buffer. The data is sent to the compositor when the client calls WlDisplay.flush().

Incoming data is handled in two steps: queueing and dispatching. In the queue step, the data coming from the display fd is interpreted and added to a queue. On the dispatch step, the handler for the incoming event set by the client on the corresponding WlProxy is called.

A WlDisplay has at least one event queue, called the <em>default queue</em>. Clients can create additional event queues with WlDisplay.createQueue() and assign WlProxy's to it. Events occurring in a particular proxy are always queued in its assigned queue. A client can ensure that a certain assumption, such as holding a lock or running from a given thread, is true when a proxy event handler is called by assigning that proxy to an event queue and making sure that this queue is only dispatched when the assumption holds.

The default queue is dispatched by calling WlDisplay.dispatch(). This will dispatch any events queued on the default queue and attempt to read from the display fd if it's empty. Events read are then queued on the appropriate queues according to the proxy assignment.

A user created queue is dispatched with WlDisplay.dispatchQueue(). This function behaves exactly the same as WlDisplay.dispatch() but it dispatches given queue instead of the default queue.

A real world example of event queue usage is Mesa's implementation of eglSwapBuffers() for the Wayland platform. This function might need to block until a frame callback is received, but dispatching the default queue could cause an event handler on the client to start drawing again. This problem is solved using another event queue, so that only the events handled by the EGL code are dispatched during the block.

This creates a problem where a thread dispatches a non-default queue, reading all the data from the display fd. If the application would call \em poll(2) after that it would block, even though there might be events queued on the default queue. Those events should be dispatched with WlDisplay.dispatchPending() or WlDisplay.dispatchQueuePending() before flushing and blocking.

Constructors

this
this(wl_display* native)
Undocumented in source.

Members

Functions

cancelRead
void cancelRead()
Undocumented in source. Be warned that the author may not have intended to support it.
createQueue
WlEventQueue createQueue()
Undocumented in source. Be warned that the author may not have intended to support it.
disconnect
void disconnect()
Undocumented in source. Be warned that the author may not have intended to support it.
dispatch
int dispatch()
Undocumented in source. Be warned that the author may not have intended to support it.
dispatchPending
int dispatchPending()
Undocumented in source. Be warned that the author may not have intended to support it.
dispatchQueue
int dispatchQueue(WlEventQueue queue)
Undocumented in source. Be warned that the author may not have intended to support it.
dispatchQueuePending
int dispatchQueuePending(WlEventQueue queue)
Undocumented in source. Be warned that the author may not have intended to support it.
flush
int flush()
Undocumented in source. Be warned that the author may not have intended to support it.
getError
int getError()
Undocumented in source. Be warned that the author may not have intended to support it.
getFd
int getFd()
Undocumented in source. Be warned that the author may not have intended to support it.
getProtocolError
immutable(WlInterface) getProtocolError(uint code, uint id)
Undocumented in source. Be warned that the author may not have intended to support it.
prepareRead
int prepareRead()
Undocumented in source. Be warned that the author may not have intended to support it.
prepareReadQueue
int prepareReadQueue(WlEventQueue queue)
Undocumented in source. Be warned that the author may not have intended to support it.
readEvents
int readEvents()
Undocumented in source. Be warned that the author may not have intended to support it.
roundtrip
int roundtrip()
Undocumented in source. Be warned that the author may not have intended to support it.
roundtripQueue
int roundtripQueue(WlEventQueue queue)
Undocumented in source. Be warned that the author may not have intended to support it.

Properties

native
inout(wl_display)* native [@property getter]
Undocumented in source. Be warned that the author may not have intended to support it.

Static functions

connect
WlDisplay connect(string name)
Undocumented in source. Be warned that the author may not have intended to support it.
connectToFd
WlDisplay connectToFd(int fd)
Undocumented in source. Be warned that the author may not have intended to support it.

Inherited Members

From WlProxy

destroyNotify
void destroyNotify()
Undocumented in source. Be warned that the author may not have intended to support it.
get
WlProxy get(wl_proxy* proxy)
Undocumented in source. Be warned that the author may not have intended to support it.
proxy
inout(wl_proxy)* proxy [@property getter]
Undocumented in source. Be warned that the author may not have intended to support it.
ver
uint ver [@property getter]

Get the protocol version of WlDisplay.

id
uint id [@property getter]

Get the id assigned to this object.

class_
string class_ [@property getter]

Get the class of this object.

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