Provided by: waylandpp-dev_1.0.0-5ubuntu2_amd64 
NAME
wayland::subsurface_t - sub-surface interface to a wl_surface
SYNOPSIS
#include <wayland-client-protocol.hpp>
Inherits wayland::proxy_t.
Public Types
enum class wrapper_type { standard, display, foreign, proxy_wrapper }
Public Member Functions
void set_position (int32_t x, int32_t y)
reposition the sub-surface
void place_above (surface_t const &sibling)
restack the sub-surface
void place_below (surface_t const &sibling)
restack the sub-surface
void set_sync ()
set sub-surface to synchronized mode
void set_desync ()
set sub-surface to desynchronized mode
uint32_t get_id () const
Get the id of a proxy object.
std::string get_class () const
Get the interface name (class) of a proxy object.
uint32_t get_version () const
Get the protocol object version of a proxy object.
wrapper_type get_wrapper_type () const
Get the type of a proxy object.
void set_queue (event_queue_t queue)
Assign a proxy to an event queue.
wl_proxy * c_ptr () const
Get a pointer to the underlying C struct.
bool proxy_has_object () const
Check whether this wrapper actually wraps an object.
operator bool () const
Check whether this wrapper actually wraps an object.
bool operator== (const proxy_t &right) const
Check whether two wrappers refer to the same object.
bool operator!= (const proxy_t &right) const
Check whether two wrappers refer to different objects.
void proxy_release ()
Release the wrapped object (if any), making this an empty wrapper.
Static Public Attributes
static constexpr std::uint32_t set_position_since_version = 1
Minimum protocol version required for the set_position function.
static constexpr std::uint32_t place_above_since_version = 1
Minimum protocol version required for the place_above function.
static constexpr std::uint32_t place_below_since_version = 1
Minimum protocol version required for the place_below function.
static constexpr std::uint32_t set_sync_since_version = 1
Minimum protocol version required for the set_sync function.
static constexpr std::uint32_t set_desync_since_version = 1
Minimum protocol version required for the set_desync function.
Detailed Description
sub-surface interface to a wl_surface
An additional interface to a wl_surface object, which has been made a sub-surface. A sub-surface has one
parent surface. A sub-surface's size and position are not limited to that of the parent. Particularly, a
sub-surface is not automatically clipped to its parent's area.
A sub-surface becomes mapped, when a non-NULL wl_buffer is applied and the parent surface is mapped. The
order of which one happens first is irrelevant. A sub-surface is hidden if the parent becomes hidden, or
if a NULL wl_buffer is applied. These rules apply recursively through the tree of surfaces.
The behaviour of a wl_surface.commit request on a sub-surface depends on the sub-surface's mode. The
possible modes are synchronized and desynchronized, see methods wl_subsurface.set_sync and
wl_subsurface.set_desync. Synchronized mode caches the wl_surface state to be applied when the parent's
state gets applied, and desynchronized mode applies the pending wl_surface state directly. A sub-surface
is initially in the synchronized mode.
Sub-surfaces also have another kind of state, which is managed by wl_subsurface requests, as opposed to
wl_surface requests. This state includes the sub-surface position relative to the parent surface
(wl_subsurface.set_position), and the stacking order of the parent and its sub-surfaces
(wl_subsurface.place_above and .place_below). This state is applied when the parent surface's wl_surface
state is applied, regardless of the sub-surface's mode. As the exception, set_sync and set_desync are
effective immediately.
The main surface can be thought to be always in desynchronized mode, since it does not have a parent in
the sub-surfaces sense.
Even if a sub-surface is in desynchronized mode, it will behave as in synchronized mode, if its parent
surface behaves as in synchronized mode. This rule is applied recursively throughout the tree of
surfaces. This means, that one can set a sub-surface into synchronized mode, and then assume that all its
child and grand-child sub-surfaces are synchronized, too, without explicitly setting them.
If the wl_surface associated with the wl_subsurface is destroyed, the wl_subsurface object becomes inert.
Note, that destroying either object takes effect immediately. If you need to synchronize the removal of a
sub-surface to the parent surface update, unmap the sub-surface first by attaching a NULL wl_buffer,
update parent, and then destroy the sub-surface.
If the parent wl_surface object is destroyed, the sub-surface is unmapped.
Definition at line 3978 of file wayland-client-protocol.hpp.
Member Enumeration Documentation
enum class wayland::proxy_t::wrapper_type [strong], [inherited]
Underlying wl_proxy type and properties of a proxy_t that affect construction, destruction, and event
handling
Enumerator
standard
C pointer is a standard type compatible with wl_proxy*. Events are dispatched and it is destructed
when the proxy_t is destructed. User data is set.
display
C pointer is a wl_display*. No events are dispatched, wl_display_disconnect is called when the
proxy_t is destructed. User data is set.
foreign
C pointer is a standard type compatible with wl_proxy*, but another library owns it and it should
not be touched in a way that could affect the operation of the other library. No events are
dispatched, wl_proxy_destroy is not called when the proxy_t is destructed, user data is not
touched. Consequently, there is no reference counting for the proxy_t. Lifetime of such wrappers
should preferably be short to minimize the chance that the owning library decides to destroy the
wl_proxy.
proxy_wrapper
C pointer is a wl_proxy* that was constructed with wl_proxy_create_wrapper. No events are
dispatched, wl_proxy_wrapper_destroy is called when the proxy_t is destroyed. Reference counting
is active. A reference to the proxy_t creating this proxy wrapper is held to extend its lifetime
until after the proxy wrapper is destroyed.
Definition at line 116 of file wayland-client.hpp.
Member Function Documentation
wl_proxy * wayland::proxy_t::c_ptr () const [inherited]
Get a pointer to the underlying C struct.
Returns
The underlying wl_proxy wrapped by this proxy_t if it exists, otherwise an exception is thrown
std::string wayland::proxy_t::get_class () const [inherited]
Get the interface name (class) of a proxy object.
Returns
The interface name of the object associated with the proxy
uint32_t wayland::proxy_t::get_id () const [inherited]
Get the id of a proxy object.
Returns
The id the object associated with the proxy
uint32_t wayland::proxy_t::get_version () const [inherited]
Get the protocol object version of a proxy object. Gets the protocol object version of a proxy object, or
0 if the proxy was created with unversioned API.
A returned value of 0 means that no version information is available, so the caller must make safe
assumptions about the object's real version.
display_t will always return version 0.
Returns
The protocol object version of the proxy or 0
wrapper_type wayland::proxy_t::get_wrapper_type () const [inline], [inherited]
Get the type of a proxy object.
Definition at line 302 of file wayland-client.hpp.
wayland::proxy_t::operator bool () const [inherited]
Check whether this wrapper actually wraps an object.
Returns
true if there is an underlying object, false if this wrapper is empty
bool wayland::proxy_t::operator!= (const proxy_t & right) const [inherited]
Check whether two wrappers refer to different objects.
bool wayland::proxy_t::operator== (const proxy_t & right) const [inherited]
Check whether two wrappers refer to the same object.
void subsurface_t::place_above (surface_t const & sibling)
restack the sub-surface
Parameters
sibling the reference surface
This sub-surface is taken from the stack, and put back just above the reference surface, changing the z-
order of the sub-surfaces. The reference surface must be one of the sibling surfaces, or the parent
surface. Using any other surface, including this sub-surface, will cause a protocol error.
The z-order is double-buffered. Requests are handled in order and applied immediately to a pending state.
The final pending state is copied to the active state the next time the state of the parent surface is
applied. When this happens depends on whether the parent surface is in synchronized mode or not. See
wl_subsurface.set_sync and wl_subsurface.set_desync for details.
A new sub-surface is initially added as the top-most in the stack of its siblings and parent.
Definition at line 3633 of file wayland-client-protocol.cpp.
void subsurface_t::place_below (surface_t const & sibling)
restack the sub-surface
Parameters
sibling the reference surface
The sub-surface is placed just below the reference surface. See wl_subsurface.place_above.
Definition at line 3639 of file wayland-client-protocol.cpp.
bool wayland::proxy_t::proxy_has_object () const [inherited]
Check whether this wrapper actually wraps an object.
Returns
true if there is an underlying object, false if this wrapper is empty
void wayland::proxy_t::proxy_release () [inherited]
Release the wrapped object (if any), making this an empty wrapper. Note that display_t instances cannot
be released this way. Attempts to do so are ignored.
Examples
foreign_display.cpp.
void subsurface_t::set_desync ()
set sub-surface to desynchronized mode Change the commit behaviour of the sub-surface to desynchronized
mode, also described as independent or freely running mode.
In desynchronized mode, wl_surface.commit on a sub-surface will apply the pending state directly, without
caching, as happens normally with a wl_surface. Calling wl_surface.commit on the parent surface has no
effect on the sub-surface's wl_surface state. This mode allows a sub-surface to be updated on its own.
If cached state exists when wl_surface.commit is called in desynchronized mode, the pending state is
added to the cached state, and applied as a whole. This invalidates the cache.
Note: even if a sub-surface is set to desynchronized, a parent sub-surface may override it to behave as
synchronized. For details, see wl_subsurface.
If a surface's parent surface behaves as desynchronized, then the cached state is applied on set_desync.
Definition at line 3651 of file wayland-client-protocol.cpp.
void subsurface_t::set_position (int32_t x, int32_t y)
reposition the sub-surface
Parameters
x x coordinate in the parent surface
y y coordinate in the parent surface
This schedules a sub-surface position change. The sub-surface will be moved so that its origin (top left
corner pixel) will be at the location x, y of the parent surface coordinate system. The coordinates are
not restricted to the parent surface area. Negative values are allowed.
The scheduled coordinates will take effect whenever the state of the parent surface is applied. When this
happens depends on whether the parent surface is in synchronized mode or not. See wl_subsurface.set_sync
and wl_subsurface.set_desync for details.
If more than one set_position request is invoked by the client before the commit of the parent surface,
the position of a new request always replaces the scheduled position from any previous request.
The initial position is 0, 0.
Definition at line 3627 of file wayland-client-protocol.cpp.
void wayland::proxy_t::set_queue (event_queue_t queue) [inherited]
Assign a proxy to an event queue.
Parameters
queue The event queue that will handle this proxy
Assign proxy to event queue. Events coming from proxy will be queued in queue instead of the display's
main queue.
See also: display_t::dispatch_queue().
Examples
proxy_wrapper.cpp.
void subsurface_t::set_sync ()
set sub-surface to synchronized mode Change the commit behaviour of the sub-surface to synchronized mode,
also described as the parent dependent mode.
In synchronized mode, wl_surface.commit on a sub-surface will accumulate the committed state in a cache,
but the state will not be applied and hence will not change the compositor output. The cached state is
applied to the sub-surface immediately after the parent surface's state is applied. This ensures atomic
updates of the parent and all its synchronized sub-surfaces. Applying the cached state will invalidate
the cache, so further parent surface commits do not (re-)apply old state.
See wl_subsurface for the recursive effect of this mode.
Definition at line 3645 of file wayland-client-protocol.cpp.
Member Data Documentation
constexpr std::uint32_t wayland::subsurface_t::place_above_since_version = 1 [static], [constexpr]
Minimum protocol version required for the place_above function.
Definition at line 4052 of file wayland-client-protocol.hpp.
constexpr std::uint32_t wayland::subsurface_t::place_below_since_version = 1 [static], [constexpr]
Minimum protocol version required for the place_below function.
Definition at line 4065 of file wayland-client-protocol.hpp.
constexpr std::uint32_t wayland::subsurface_t::set_desync_since_version = 1 [static], [constexpr]
Minimum protocol version required for the set_desync function.
Definition at line 4117 of file wayland-client-protocol.hpp.
constexpr std::uint32_t wayland::subsurface_t::set_position_since_version = 1 [static], [constexpr]
Minimum protocol version required for the set_position function.
Definition at line 4026 of file wayland-client-protocol.hpp.
constexpr std::uint32_t wayland::subsurface_t::set_sync_since_version = 1 [static], [constexpr]
Minimum protocol version required for the set_sync function.
Definition at line 4088 of file wayland-client-protocol.hpp.
Author
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Version 1.0.0 Mon Apr 22 2024 09:52:15 wayland::subsurface_t(3)