.TH "wayland::subcompositor_t" 3 "Wed May 3 2023" "Version 1.0.0" "Wayland++" \" -*- nroff -*- .ad l .nh .SH NAME wayland::subcompositor_t \- sub-surface compositing .SH SYNOPSIS .br .PP .PP \fC#include \fP .PP Inherits \fBwayland::proxy_t\fP\&. .SS "Public Types" .in +1c .ti -1c .RI "enum class \fBwrapper_type\fP { \fBstandard\fP, \fBdisplay\fP, \fBforeign\fP, \fBproxy_wrapper\fP }" .br .in -1c .SS "Public Member Functions" .in +1c .ti -1c .RI "\fBsubsurface_t\fP \fBget_subsurface\fP (\fBsurface_t\fP const &surface, \fBsurface_t\fP const &parent)" .br .RI "give a surface the role sub-surface " .ti -1c .RI "uint32_t \fBget_id\fP () const" .br .RI "Get the id of a proxy object\&. " .ti -1c .RI "std::string \fBget_class\fP () const" .br .RI "Get the interface name (class) of a proxy object\&. " .ti -1c .RI "uint32_t \fBget_version\fP () const" .br .RI "Get the protocol object version of a proxy object\&. " .ti -1c .RI "\fBwrapper_type\fP \fBget_wrapper_type\fP () const" .br .RI "Get the type of a proxy object\&. " .ti -1c .RI "void \fBset_queue\fP (\fBevent_queue_t\fP queue)" .br .RI "Assign a proxy to an event queue\&. " .ti -1c .RI "wl_proxy * \fBc_ptr\fP () const" .br .RI "Get a pointer to the underlying C struct\&. " .ti -1c .RI "bool \fBproxy_has_object\fP () const" .br .RI "Check whether this wrapper actually wraps an object\&. " .ti -1c .RI "\fBoperator bool\fP () const" .br .RI "Check whether this wrapper actually wraps an object\&. " .ti -1c .RI "bool \fBoperator==\fP (const \fBproxy_t\fP &right) const" .br .RI "Check whether two wrappers refer to the same object\&. " .ti -1c .RI "bool \fBoperator!=\fP (const \fBproxy_t\fP &right) const" .br .RI "Check whether two wrappers refer to different objects\&. " .ti -1c .RI "void \fBproxy_release\fP ()" .br .RI "Release the wrapped object (if any), making this an empty wrapper\&. " .in -1c .SS "Static Public Attributes" .in +1c .ti -1c .RI "static constexpr std::uint32_t \fBget_subsurface_since_version\fP = 1" .br .RI "Minimum protocol version required for the \fBget_subsurface\fP function\&. " .in -1c .SH "Detailed Description" .PP sub-surface compositing The global interface exposing sub-surface compositing capabilities\&. A wl_surface, that has sub-surfaces associated, is called the parent surface\&. Sub-surfaces can be arbitrarily nested and create a tree of sub-surfaces\&. .PP The root surface in a tree of sub-surfaces is the main surface\&. The main surface cannot be a sub-surface, because sub-surfaces must always have a parent\&. .PP A main surface with its sub-surfaces forms a (compound) window\&. For window management purposes, this set of wl_surface objects is to be considered as a single window, and it should also behave as such\&. .PP The aim of sub-surfaces is to offload some of the compositing work within a window from clients to the compositor\&. A prime example is a video player with decorations and video in separate wl_surface objects\&. This should allow the compositor to pass YUV video buffer processing to dedicated overlay hardware when possible\&. .PP Definition at line \fB3863\fP of file \fBwayland\-client\-protocol\&.hpp\fP\&. .SH "Member Enumeration Documentation" .PP .SS "enum class \fBwayland::proxy_t::wrapper_type\fP\fC [strong]\fP, \fC [inherited]\fP" Underlying wl_proxy type and properties of a \fBproxy_t\fP that affect construction, destruction, and event handling .PP \fBEnumerator\fP .in +1c .TP \fB\fIstandard \fP\fP C pointer is a standard type compatible with wl_proxy*\&. Events are dispatched and it is destructed when the \fBproxy_t\fP is destructed\&. User data is set\&. .TP \fB\fIdisplay \fP\fP C pointer is a wl_display*\&. No events are dispatched, wl_display_disconnect is called when the \fBproxy_t\fP is destructed\&. User data is set\&. .TP \fB\fIforeign \fP\fP 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 \fBproxy_t\fP is destructed, user data is not touched\&. Consequently, there is no reference counting for the \fBproxy_t\fP\&. Lifetime of such wrappers should preferably be short to minimize the chance that the owning library decides to destroy the wl_proxy\&. .TP \fB\fIproxy_wrapper \fP\fP 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 \fBproxy_t\fP is destroyed\&. Reference counting is active\&. A reference to the \fBproxy_t\fP creating this proxy wrapper is held to extend its lifetime until after the proxy wrapper is destroyed\&. .PP Definition at line \fB115\fP of file \fBwayland\-client\&.hpp\fP\&. .SH "Member Function Documentation" .PP .SS "wl_proxy * wayland::proxy_t::c_ptr () const\fC [inherited]\fP" .PP Get a pointer to the underlying C struct\&. .PP \fBReturns\fP .RS 4 The underlying wl_proxy wrapped by this \fBproxy_t\fP if it exists, otherwise an exception is thrown .RE .PP .SS "std::string wayland::proxy_t::get_class () const\fC [inherited]\fP" .PP Get the interface name (class) of a proxy object\&. .PP \fBReturns\fP .RS 4 The interface name of the object associated with the proxy .RE .PP .SS "uint32_t wayland::proxy_t::get_id () const\fC [inherited]\fP" .PP Get the id of a proxy object\&. .PP \fBReturns\fP .RS 4 The id the object associated with the proxy .RE .PP .SS "\fBsubsurface_t\fP subcompositor_t::get_subsurface (\fBsurface_t\fP const & surface, \fBsurface_t\fP const & parent)" .PP give a surface the role sub-surface .PP \fBReturns\fP .RS 4 the new sub-surface object ID .RE .PP \fBParameters\fP .RS 4 \fIsurface\fP the surface to be turned into a sub-surface .br \fIparent\fP the parent surface .RE .PP Create a sub-surface interface for the given surface, and associate it with the given parent surface\&. This turns a plain wl_surface into a sub-surface\&. .PP The to-be sub-surface must not already have another role, and it must not have an existing wl_subsurface object\&. Otherwise a protocol error is raised\&. .PP Adding sub-surfaces to a parent is a double-buffered operation on the parent (see wl_surface\&.commit)\&. The effect of adding a sub-surface becomes visible on the next time the state of the parent surface is applied\&. .PP This request modifies the behaviour of wl_surface\&.commit request on the sub-surface, see the documentation on wl_subsurface interface\&. .PP Definition at line \fB3563\fP of file \fBwayland\-client\-protocol\&.cpp\fP\&. .SS "uint32_t wayland::proxy_t::get_version () const\fC [inherited]\fP" .PP 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\&. .PP 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\&. .PP \fBdisplay_t\fP will always return version 0\&. .PP \fBReturns\fP .RS 4 The protocol object version of the proxy or 0 .RE .PP .SS "\fBwrapper_type\fP wayland::proxy_t::get_wrapper_type () const\fC [inline]\fP, \fC [inherited]\fP" .PP Get the type of a proxy object\&. .PP Definition at line \fB301\fP of file \fBwayland\-client\&.hpp\fP\&. .SS "wayland::proxy_t::operator bool () const\fC [inherited]\fP" .PP Check whether this wrapper actually wraps an object\&. .PP \fBReturns\fP .RS 4 true if there is an underlying object, false if this wrapper is empty .RE .PP .SS "bool wayland::proxy_t::operator!= (const \fBproxy_t\fP & right) const\fC [inherited]\fP" .PP Check whether two wrappers refer to different objects\&. .SS "bool wayland::proxy_t::operator== (const \fBproxy_t\fP & right) const\fC [inherited]\fP" .PP Check whether two wrappers refer to the same object\&. .SS "bool wayland::proxy_t::proxy_has_object () const\fC [inherited]\fP" .PP Check whether this wrapper actually wraps an object\&. .PP \fBReturns\fP .RS 4 true if there is an underlying object, false if this wrapper is empty .RE .PP .SS "void wayland::proxy_t::proxy_release ()\fC [inherited]\fP" .PP Release the wrapped object (if any), making this an empty wrapper\&. Note that \fBdisplay_t\fP instances cannot be released this way\&. Attempts to do so are ignored\&. .PP \fBExamples\fP .in +1c \fBforeign_display\&.cpp\fP\&. .SS "void wayland::proxy_t::set_queue (\fBevent_queue_t\fP queue)\fC [inherited]\fP" .PP Assign a proxy to an event queue\&. .PP \fBParameters\fP .RS 4 \fIqueue\fP The event queue that will handle this proxy .RE .PP Assign proxy to event queue\&. Events coming from proxy will be queued in queue instead of the display's main queue\&. .PP See also: \fBdisplay_t::dispatch_queue()\fP\&. .PP \fBExamples\fP .in +1c \fBproxy_wrapper\&.cpp\fP\&. .SH "Member Data Documentation" .PP .SS "constexpr std::uint32_t wayland::subcompositor_t::get_subsurface_since_version = 1\fC [static]\fP, \fC [constexpr]\fP" .PP Minimum protocol version required for the \fBget_subsurface\fP function\&. .PP Definition at line \fB3911\fP of file \fBwayland\-client\-protocol\&.hpp\fP\&. .SH "Author" .PP Generated automatically by Doxygen for Wayland++ from the source code\&.