[PATCH wayland-protocols v3 1/7] xdg-shell: Turn xdg_surface into a generic base interface
Jonas Ådahl
jadahl at gmail.com
Wed Jun 8 01:18:05 UTC 2016
On Wed, Jun 08, 2016 at 12:37:01AM +0200, Benoit Gschwind wrote:
> Hello,
>
> This proposal look good, few optional comments following.
>
> On 26/05/2016 06:32, Jonas Ådahl wrote:
> > Split out toplevel window like requests and events into a new interface
> > called xdg_toplevel, and turn xdg_surface into a generic base interface
> > which others extends.
> >
> > xdg_popup is changed to extend the xdg_surface.
> >
> > The configure event in xdg_surface was split up making
> > xdg_surface.configure an event only carrying the serial number, while a
> > new xdg_toplevel.configure event carries the other data previously sent
> > via xdg_surface.configure. xdg_toplevel.configure is made to extend,
> > via the latch-state mechanism, xdg_surface.configure and depends on
> > that event to synchronize state.
> >
> > Other future xdg_surface based extensions are meant to also extend
> > xdg_surface.configure for relevant window type dependend state
> > synchronization.
> >
> > Signed-off-by: Jonas Ådahl <jadahl at gmail.com>
> > Signed-off-by: Mike Blumenkrantz <zmike at samsung.com>
> > ---
> >
> > Changes since v2:
> > - Grammar, typos and spelling fixes
> > - Tried to clarify the latched state configure events sequence
> > - Clarified window geometry constraints and semantics
> >
> >
> > unstable/xdg-shell/xdg-shell-unstable-v6.xml | 275 ++++++++++++++++-----------
> > 1 file changed, 165 insertions(+), 110 deletions(-)
> >
> > diff --git a/unstable/xdg-shell/xdg-shell-unstable-v6.xml b/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> > index ce57153..fa838f9 100644
> > --- a/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> > +++ b/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> > @@ -54,11 +54,9 @@
> >
> > <request name="get_xdg_surface">
> > <description summary="create a shell surface from a surface">
> > - This creates an xdg_surface for the given surface and gives it the
> > - xdg_surface role. A wl_surface can only be given an xdg_surface role
> > - once. If get_xdg_surface is called with a wl_surface that already has
> > - an active xdg_surface associated with it, or if it had any other role,
> > - an error is raised.
> > + This creates an xdg_surface for the given surface. While xdg_surface
> > + itself is not a role, the corresponding surface may only be assigned
> > + a role extending xdg_surface, such as xdg_toplevel or xdg_popup.
> >
>
> I think the 3 line above are more confusing than useful and may be
> replaced by the single sentence:
> This creates an xdg_surface for the given surface.
I think it helps describing the expectations here.
>
> > See the documentation of xdg_surface for more details about what an
> > xdg_surface is and how it is used.
> > @@ -67,29 +65,6 @@
> > <arg name="surface" type="object" interface="wl_surface"/>
> > </request>
> >
> > - <request name="get_xdg_popup">
> > - <description summary="create a popup for a surface">
> > - This creates an xdg_popup for the given surface and gives it the
> > - xdg_popup role. A wl_surface can only be given an xdg_popup role
> > - once. If get_xdg_popup is called with a wl_surface that already has
> > - an active xdg_popup associated with it, or if it had any other role,
> > - an error is raised.
> > -
> > - This request must be used in response to some sort of user action
> > - like a button press, key press, or touch down event.
> > -
> > - See the documentation of xdg_popup for more details about what an
> > - xdg_popup is and how it is used.
> > - </description>
> > - <arg name="id" type="new_id" interface="zxdg_popup_v6"/>
> > - <arg name="surface" type="object" interface="wl_surface"/>
> > - <arg name="parent" type="object" interface="wl_surface"/>
> > - <arg name="seat" type="object" interface="wl_seat" summary="the wl_seat of the user event"/>
> > - <arg name="serial" type="uint" summary="the serial of the user event"/>
> > - <arg name="x" type="int"/>
> > - <arg name="y" type="int"/>
> > - </request>
> > -
> > <event name="ping">
> > <description summary="check if the client is alive">
> > The ping event asks the client if it's still alive. Pass the
> > @@ -117,13 +92,23 @@
> > </interface>
> >
> > <interface name="zxdg_surface_v6" version="1">
> > - <description summary="A desktop window">
> > + <description summary="desktop user interface surface base interface">
> > An interface that may be implemented by a wl_surface, for
> > implementations that provide a desktop-style user interface.
> >
> > - It provides requests to treat surfaces like windows, allowing to set
> > - properties like maximized, fullscreen, minimized, and to move and resize
> > - them, and associate metadata like title and app id.
> > + It provides a base set of functionality required to construct user
> > + interface elements requiring management by the compositor, such as
> > + toplevel windows, menus, etc. The types of functionality are split into
> > + xdg_surface roles.
> > +
> > + Creating an xdg_surface does not set the role for a wl_surface. In order
> > + to map an xdg_surface, create a role-specific object using, e.g.,
>
> In order to map an xdg_surface, the client must create a role-specific ...
Sure.
>
> > + get_toplevel, get_popup. The wl_surface for any given xdg_surface can
> > + have at most one role, and may not be assigned any role not based on
> > + xdg_surface.
> > +
> > + A role must be assigned before any other requests are made to the
> > + xdg_surface object.
> >
> > The client must call wl_surface.commit on the corresponding wl_surface
> > for the xdg_surface state to take effect.
> > @@ -133,12 +118,146 @@
> > manipulate a buffer prior to the first xdg_surface.configure call must
> > also be treated as errors.
> >
> > - For a surface to be mapped by the compositor the client must have
> > - committed both an xdg_surface state and a buffer.
> > + For a surface to be mapped by the compositor the client must have assigned
> > + one of the xdg_surface based roles, it must have committed both the
> > + xdg_surface state and the role dependent state, and it must have committed
> > + a buffer.
>
> For a surface to be mapped by the compositor, the following conditions
> must be met: (1) the client has assigned a xdg_surface based role to the
> surface, (2) the client has set the xdg_surface state and the role
> dependent state to the surface and (3) the client has committed a buffer
> to the surface.
Sure, that makes it a bit clearer.
>
> > + </description>
> > +
> > + <enum name="error">
> > + <entry name="not_constructed" value="1"/>
> > + <entry name="already_constructed" value="2"/>
> > + </enum>
> > +
> > + <request name="destroy" type="destructor">
> > + <description summary="destroy the xdg_surface">
> > + Destroy the xdg_surface object. An xdg_surface must only be destroyed
> > + after its role object has been destroyed.
> > + </description>
> > + </request>
> > +
> > + <request name="get_toplevel">
> > + <description summary="assign the xdg_toplevel surface role">
> > + This creates an xdg_toplevel object for the given xdg_surface and gives
> > + the associated wl_surface the xdg_toplevel role.
> > +
> > + See the documentation of xdg_toplevel for more details about what an
> > + xdg_toplevel is and how it is used.
> > + </description>
> > + <arg name="id" type="new_id" interface="zxdg_toplevel_v6"/>
> > + </request>
> > +
> > + <request name="get_popup">
> > + <description summary="assign the xdg_popup surface role">
> > + This creates an xdg_popup object for the given xdg_surface and gives the
> > + associated wl_surface the xdg_popup role.
> > +
> > + This request must be used in response to some sort of user action like a
> > + button press, key press, or touch down event.
> > +
> > + See the documentation of xdg_popup for more details about what an
> > + xdg_popup is and how it is used.
> > + </description>
> > + <arg name="id" type="new_id" interface="zxdg_popup_v6"/>
> > + <arg name="parent" type="object" interface="wl_surface"/>
> > + <arg name="seat" type="object" interface="wl_seat" summary="the wl_seat of the user event"/>
> > + <arg name="serial" type="uint" summary="the serial of the user event"/>
> > + <arg name="x" type="int"/>
> > + <arg name="y" type="int"/>
> > + </request>
> > +
> > + <request name="set_window_geometry">
> > + <description summary="set the new window geometry">
> > + The window geometry of a surface is its "visible bounds" from the
> > + user's perspective. Client-side decorations often have invisible
> > + portions like drop-shadows which should be ignored for the
> > + purposes of aligning, placing and constraining windows.
> > +
> > + The window geometry is double buffered, and will be applied at the
> > + time wl_surface.commit of the corresponding wl_surface is called.
> > +
> > + Once the window geometry of the surface is set, it is not possible to
> > + unset it, and it will remain the same until set_window_geometry is
> > + called again, even if a new subsurface or buffer is attached.
> > +
> > + If never set, the value is the full bounds of the surface,
> > + including any subsurfaces. This updates dynamically on every
> > + commit. This unset is meant for extremely simple clients.
>
> This sentence was from the previous spec. but I would use :
>
> This defaults behavior is meant for simplest clients.
>
> maybe could be done in another patch.
Yea, lets that would be better as a follow up.
>
>
> > +
> > + The arguments are given in the surface-local coordinate space of
> > + the wl_surface associated with this xdg_surface.
> > +
> > + The width and height must be greater than zero. Setting an invalid size
> > + will raise an error. When applied, the effective window geometry will be
> > + the set window geometry clamped to the bounding rectangle of the
> > + combined geometry of the surface of the xdg_surface and the associated
> > + subsurfaces.
> > + </description>
> > + <arg name="x" type="int"/>
> > + <arg name="y" type="int"/>
> > + <arg name="width" type="int"/>
> > + <arg name="height" type="int"/>
> > + </request>
> > +
> > + <request name="ack_configure">
> > + <description summary="ack a configure event">
> > + When a configure event is received, if a client commits the
> > + surface in response to the configure event, then the client
> > + must make an ack_configure request sometime before the commit
> > + request, passing along the serial of the configure event.
> > +
> > + For instance, for toplevel surfaces the compositor might use this
> > + information to move a surface to the top left only when the client has
> > + drawn itself for the maximized or fullscreen state.
> > +
> > + If the client receives multiple configure events before it
> > + can respond to one, it only has to ack the last configure event.
> > +
> > + A client is not required to commit immediately after sending
> > + an ack_configure request - it may even ack_configure several times
> > + before its next surface commit.
> > +
> > + A client may send multiple ack_configure requests before committing, but
> > + only the last request sent before a commit indicates which configure
> > + event the client really is responding to.
> > + </description>
> > + <arg name="serial" type="uint" summary="the serial from the configure event"/>
> > + </request>
> > +
> > + <event name="configure">
> > + <description summary="suggest a surface change">
> > + The configure event marks the end of a configure sequence. A configure
> > + sequence is a set of zero or more events configuring the drawing of the
> > + surface, finalized by this event.
>
> A configure sequence is a set of one or more events configuring the
> state of the xdg_surface, including the final xdg_surface.configure event.
Yes, that sounds better.
>
> > +
> > + Where applicable, xdg_surface surface roles will during a configure
> > + sequence extend this event as a latched state sent as events before the
> > + xdg_surface.configure event. Such events should be considered to make up
> > + a set of atomically applied configuration states, where the
> > + xdg_surface.configure commits the accumulated state.
>
> I tried to figure out what the paragraph above explain. Here is my
> rewording, If I'm wrong please correct myself and feel free to pick my
> wording to improve this paragraph.
>
> The client must freeze the state of a window until a configure sequence
> is completed. During the configure sequence the client accumulate state
> changes. When and only when the client receive a xdg_surface.configure
> event, the client can apply accumulated changes of the surface state.
> During the configure sequence, a newer events override all previous
> event of the same type.
Yes, except I would assume a client wouldn't "freeze" anything, but
would rather accumulate the changes in a "pending state" container
similar to how the compositor handles surface state changes before
wl_surface.commit.
>
> > +
> > + Clients should arrange their surface for the new states, and then send
> > + an ack_configure request with the serial sent in this configure event at
> > + some point before committing the new surface.
> > +
> > + If the client receives multiple configure events before it can respond
> > + to one, it is free to discard all but the last event it received.
> > + </description>
> > + <arg name="serial" type="uint" summary="serial of the configure event"/>
> > + </event>
> > + </interface>
> > +
> > + <interface name="zxdg_toplevel_v6" version="1">
> > + <description summary="toplevel surface">
> > + This interface defines an xdg_surface role which allows a surface to,
> > + among other things, set window-like properties such as maximize,
> > + fullscreen, and minimize, set application-specific metadata like title and
> > + id, and well as trigger user interactive operations such as interactive
> > + resize and move.
> > </description>
> >
> > <request name="destroy" type="destructor">
> > - <description summary="Destroy the xdg_surface">
> > + <description summary="destroy the xdg_toplevel">
> > Unmap and destroy the window. The window will be effectively
> > hidden from the user's point of view, and all state like
> > maximization, fullscreen, and so on, will be lost.
> > @@ -155,7 +274,7 @@
> > "auxiliary" surfaces, so that the parent is raised when the dialog
> > is raised.
> > </description>
> > - <arg name="parent" type="object" interface="zxdg_surface_v6" allow-null="true"/>
> > + <arg name="parent" type="object" interface="zxdg_toplevel_v6" allow-null="true"/>
> > </request>
> >
> > <request name="set_title">
> > @@ -348,8 +467,10 @@
> >
> > <event name="configure">
> > <description summary="suggest a surface change">
> > - The configure event asks the client to resize its surface or to
> > - change its state.
> > + This configure event asks the client to resize its toplevel surface or
> > + to change its state. It is not sent by itself but as a latched state
> > + sent prior to the xdg_surface.configure event. See xdg_surface.configure
> > + for details.
>
> This configure event asks the client to resize or to change states of
> the client surface. This event is not applied immediately, see
> xdg_surface.configure for details.
Maybe "The configured state should not be applied immediately. See
xdg_surface.configure for details."?
>
> >
> > The width and height arguments specify a hint to the window
> > about how its surface should be resized in window geometry
> > @@ -364,81 +485,15 @@
> > arguments should be interpreted, and possibly how it should be
> > drawn.
> >
> > - Clients should arrange their surface for the new size and
> > - states, and then send a ack_configure request with the serial
> > - sent in this configure event at some point before committing
> > - the new surface.
> > -
> > - If the client receives multiple configure events before it
> > - can respond to one, it is free to discard all but the last
> > - event it received.
> > + Clients must send an ack_configure in response to this event. See
> > + xdg_surface.configure and xdg_surface.ack_configure for details.
> > </description>
> >
> > <arg name="width" type="int"/>
> > <arg name="height" type="int"/>
> > <arg name="states" type="array"/>
> > - <arg name="serial" type="uint"/>
> > </event>
> >
> > - <request name="ack_configure">
> > - <description summary="ack a configure event">
> > - When a configure event is received, if a client commits the
> > - surface in response to the configure event, then the client
> > - must make an ack_configure request sometime before the commit
> > - request, passing along the serial of the configure event.
> > -
> > - For instance, the compositor might use this information to move
> > - a surface to the top left only when the client has drawn itself
> > - for the maximized or fullscreen state.
> > -
> > - If the client receives multiple configure events before it
> > - can respond to one, it only has to ack the last configure event.
> > -
> > - A client is not required to commit immediately after sending
> > - an ack_configure request - it may even ack_configure several times
> > - before its next surface commit.
> > -
> > - The compositor expects that the most recently received
> > - ack_configure request at the time of a commit indicates which
> > - configure event the client is responding to.
> > - </description>
> > - <arg name="serial" type="uint" summary="the serial from the configure event"/>
> > - </request>
> > -
> > - <request name="set_window_geometry">
> > - <description summary="set the new window geometry">
> > - The window geometry of a window is its "visible bounds" from the
> > - user's perspective. Client-side decorations often have invisible
> > - portions like drop-shadows which should be ignored for the
> > - purposes of aligning, placing and constraining windows.
> > -
> > - The window geometry is double buffered, and will be applied at the
> > - time wl_surface.commit of the corresponding wl_surface is called.
> > -
> > - Once the window geometry of the surface is set once, it is not
> > - possible to unset it, and it will remain the same until
> > - set_window_geometry is called again, even if a new subsurface or
> > - buffer is attached.
> > -
> > - If never set, the value is the full bounds of the surface,
> > - including any subsurfaces. This updates dynamically on every
> > - commit. This unset mode is meant for extremely simple clients.
> > -
> > - If responding to a configure event, the window geometry in here
> > - must respect the sizing negotiations specified by the states in
> > - the configure event.
> > -
> > - The arguments are given in the surface local coordinate space of
> > - the wl_surface associated with this xdg_surface.
> > -
> > - The width and height must be greater than zero.
> > - </description>
> > - <arg name="x" type="int"/>
> > - <arg name="y" type="int"/>
> > - <arg name="width" type="int"/>
> > - <arg name="height" type="int"/>
> > - </request>
> > -
> > <request name="set_max_size">
> > <description summary="set the maximum size">
> > Set a maximum size for the window.
> > @@ -447,7 +502,7 @@
> > not try to configure the window beyond this size.
> >
> > The width and height arguments are in window geometry coordinates.
> > - See set_window_geometry.
> > + See xdg_surface.set_window_geometry.
> >
> > Values set in this way are double-buffered. They will get applied
> > on the next commit.
> > @@ -488,7 +543,7 @@
> > not try to configure the window below this size.
> >
> > The width and height arguments are in window geometry coordinates.
> > - See set_window_geometry.
> > + See xdg_surface.set_window_geometry.
> >
> > Values set in this way are double-buffered. They will get applied
> > on the next commit.
> > @@ -631,7 +686,7 @@
> > their own is clicked should dismiss the popup using the destroy
> > request.
> >
> > - The parent surface must have either an xdg_surface or xdg_popup
> > + The parent surface must have either the xdg_toplevel or xdg_popup surface
> > role.
> >
> > Specifying an xdg_popup for the parent means that the popups are
> > @@ -653,7 +708,7 @@
> > The x and y arguments passed when creating the popup object specify
> > where the top left of the popup should be placed, relative to the
> > local surface coordinates of the parent surface. See
> > - xdg_shell.get_xdg_popup.
> > + xdg_surface.get_popup.
> >
> > The client must call wl_surface.commit on the corresponding wl_surface
> > for the xdg_popup state to take effect.
> >
>
> Best regards
Thanks for taking a look
Jonas
> --
> Benoit Gschwind
>
More information about the wayland-devel
mailing list