Core wayland protocol
- - surface.set_grab_mode(GRAB_OWNER_EVENTS vs GRAB_SURFACE_EVENTS), to
- make menus work right: click and drag in a menubar grabs the
- pointer to the menubar (which we need for detecting motion into
- another menu item), but we need events for the popup menu surface
- as well.
+ - Maybe try to make remote wayland actually happen, to see if there
+ is something in the protocol/architecture that makes it harder than
+ it should be.
- - The message format has to include information about number of fds
- in the message so we can skip a message correctly. Or we should
- just give up on trying to recover from unknown messages.
+ICCCM
- - generate pointer_focus (and drag focus) on raise/lower, move
- windows, all kinds of changes in surface stacking.
+ - mime-type guidelines for data_source (ie, both dnd and selection):
+ recommended types for text or images, types that a clipboard
+ manager must support, mime-types must be listed in preferred order
- - glyph cache
+ - we need a "no kb focus please" mechanism. Or should this be
+ implicit in a specific surface type?
- buffer = drm.create_buffer(); /* buffer with stuff in it */
+EWMH
- cache.upload(buffer, x, y, width, height, int key)
+ - configure should provide dx_left, dx_right, dy_top, dy_bottom, or
+ dx, dy, width and height.
- drm.buffer: id, name, stride etc /* event to announce cache buffer */
+ - move to workspace, keep on top, on all workspaces, minimize etc
+ requests for implementing client side window menu? or just make a
+ "show window menu" request to let the compositor display and manage
+ a popup window?
- cache.image: key, buffer, x, y, stride /* event to announce
- * location in cache */
+ - window move and resize functionality for kb and touch.
- cache.retire: buffer /* cache has stopped using buffer, please
- * reupload whatever you had in that buffer */
+ - Protocol for specifying title bar rectangle (for moving
+ unresponsive apps). Rectangle for close button, so we can popup
+ force-close dialog if application doesn't respond to ping event
+ when user clicks there. We could use the region mechanism here
+ too.
+ - popup placement protocol logic.
- - DnD issues:
+ - subsurface mechanism. we need this for cases where we would use an
+ X subwindow for gl or video other different visual type.
- Root window must send NULL type (to decline drop) or
- x-wayland/root-something type if the source offers that. But the
- target deletes the drag_offer object when drag.pointer_focus leaves
- the surface...
+EGL/gbm
- How do we animate the drag icon back to the drag origin in case of
- a failed drag?
+ - Land Robert Braggs EGL extensions: frame age, swap with damage
- How to handle surfaces from clients that don't know about dnd or
- don't care? Maybe the dnd object should have a
- dnd.register_surface() method so clients can opt-in the surfaces
- that will participate in dnd. Or just assume client is not
- participating until we receive an accept request.
+ - Make it possible to share buffers from compositor to clients.
+ Tricky part here is how to indicate to EGL on the server side that
+ it should make an EGLImage available to a client. We'll need a
+ "create a wl_buffer for this EGLImage for this client" kind of
+ entry point.
- - Selection/copy+paste
+ - Protocol for arbitrating access to scanout buffers (physically
+ contiguous memory). When a client goes fullscreen (or ideally as
+ the compositor starts the animation that will make it fullscreen)
+ we send a "give up your scanout buffer" to the current fullscreen
+ client (if any) and when the client acks that we send a "try to
+ allocate a scanout buffer now" event to the fullscreen-to-be
+ client.
- - Similar to dnd, create a selection object for a device to offer
- selection data:
- selection = shell.create(input_device)
+Misc
- Requests:
- - selection.offer(type)
- - selection.activate(time)
- - selection.destroy()
-
- Events:
- - selection.finish(type, fd)
- - selection.discard() /* somebody else took the selection */
-
- - Notes: no window owner, which seems to be mostly there as a way
- to identify the client and to allow None (instead of a release
- request). Possibly also to make the selection go away
- automatically when the window with the contents go away, or
- possibly as a way for the source to distinguish between multiple
- selections. Toolkits generally just create a dummy-toplevel for
- selections though.
-
- - Per-device selection. The selection is per device. Different
- keyboards copy and paste to different selections.
+ - glyph cache
- - Selection offer object. Introduced just before a surface
- receives keyboard_focus event or when somebody claims the
- selection and on keyboard_focus? That way only keyboard_focus
- owner will know the types... limits pasting to the
- keyboard_focus surface.
+ - Needs a mechanism to pass buffers to client.
- Requests:
- - selection_offer.receive(type, fd)
+ buffer = drm.create_buffer(); /* buffer with stuff in it */
- Events:
- - selection_offer.offer(type)
- - selection_offer.keyboard_focus()
+ cache.upload(buffer, x, y, width, height, int hash)
- - Pointer image issue:
+ drm.buffer: id, name, stride etc /* event to announce cache buffer */
- - A touch input device doesn't have a pointer; indicate that
- somehow.
+ cache.image: hash, buffer, x, y, stride /* event to announce
+ * location in cache */
- - Cursor themes, tie in with glyph/image cache.
+ cache.reject: hash /* no upload for you! */
- - copy-n-paste, store data in server (only one mime-type available)
- or do X style (content mime-type negotiation, but data goes away
- when client quits).
+ cache.retire: buffer /* cache has stopped using buffer, please
+ * reupload whatever you had in that buffer */
- - Discard buffer, as in "wayland discarded your buffer, it's no
- longer visible, you can stop updating it now.", reattach, as in "oh
- hey, I'm about to show your buffer that I threw away, what was it
+ - A "please suspend" event from the compositor, to indicate to an
+ application that it's no longer visible/active. Or maybe discard
+ buffer, as in "wayland discarded your buffer, it's no longer
+ visible, you can stop updating it now.", reattach, as in "oh hey,
+ I'm about to show your buffer that I threw away, what was it
again?". for wayland system compositor vt switcing, for example,
to be able to throw away the surfaces in the session we're
switching away from. for minimized windows that we don't want live
thumb nails for. etc.
- - Initial placement of surfaces. Guess we can do, 1)
- surface-relative (menus), 2) pointer-relative (tooltips and
- right-click menus) or 3) server-decides (all other top-levels).
-
- - Per client id space. Each client has an entire 32 bit id namespace
- to itself. On the server side, each struct wl_client has an object
- hash table. Object announcements use a server id space and clients
- must respond with subscribe request with a client id for the
- object. Part of wl_proxy_create_for_id():
-
- wl_display_subscribe(display, id, new_id, my_version);
-
- or maybe
-
- wl_display_bind(display, id, new_id, my_version);
-
- Fixes a few things:
-
- - Maps the global object into the client id space, lets client
- allocate the id. All ids are allocated by the client this way,
- which fixes the range protocol problem.
-
- - Tells the server that the client is interested in events from
- the object. Lets the server know that a client participates in a
- certain protocol (like drag and drop), so the server can account
- for whether or not the client is expected to reply
-
- - Server emits initial object state event(s) in reponse to
- receiving the subscribe request. Introduces an extra round trip
- at initialization time, but the server will still announces all
- objects in one burst and the client can subscribe in a burst as
- well.
-
- - Separates client resources, since each client will have it's own
- hash table. It's not longer possible to guess the id of another
- surface and access it.
-
- - Server must track the client id for each client an object is
- exposed to. In some cases we know this (a surface is always
- only owned by one client), in other cases it provides a way to
- track who's interested in the object events. For input device
- events, we can look up the client name when it receives pointer
- focus or keyboard focus and cache it in the device.
-
- - Server must know which id to send when passing object references
- in events. We could say that any object we're passing to a
- client must have a server id, and each client has a server id ->
- client id hash.
-
- - When a surface is the size of the screen and on top, we can set the
- scanout buffer to that surface directly. Like compiz unredirect
- top-level window feature. Except it won't have any protocol state
- side-effects and the client that owns the surface won't know. We
- lose control of updates. Should work well for X server root window
- under wayland. Should be possible for yuv overlays as well.
-
- - what about cursors then? maybe use hw cursors if the cursor
- satisfies hw limitations (64x64, only one cursor), switch to
- composited cursors if not.
-
- - clients needs to allocate the surface to be suitable for
- scanout, which they can do whenever they go fullscreen.
-
- - multihead, screen geometry and crtc layout protocol, hotplug
-
- - input device discovery, hotplug
-
- - Advertise axes as part of the discovery, use something like
- "org.wayland.input.x" to identify the axes.
-
- - keyboard state, layout events at connect time and when it
- changes, keyboard leds
-
- - relative events
-
- - multi touch?
-
- - synaptics, 3-button emulation, scim
-
- - auth; We need to generate a random socket name and advertise that
- on dbus along with a connection cookie. Something like a method
- that returns the socket name and a connection cookie. The
- connection cookie is just another random string that the client
- must pass to the wayland server to become authenticated. The
- Wayland server generates the cookie on demand when the dbus method
- is called and expires it after 5s or so.
-
- - or just pass the fd over dbus
-
- - drm bo access control, authentication, flink_to
-
- - Range protocol may not be sufficient... if a server cycles through
- 2^32 object IDs we don't have a way to handle wrapping. And since
- we hand out a range of 256 IDs to each new clients, we're just
- talking about 2^24 clients. That's 31 years with a new client
- every minute... Maybe just use bigger ranges, then it's feasible
- to track and garbage collect them when a client dies.
-
- - Add protocol to let applications specify the effective/logical
- surface rectangle, that is, the edge of the window, ignoring drop
- shadows and other padding. The compositor needs this for snapping
- and constraining window motion. Also, maybe communicate the opaque
- region of the window (or just a conservative, simple estimate), to
- let the compositor reduce overdraw.
-
- - multi gpu, needs queue and seqno to wait on in requests
Clients and ports
the menu and swallows the click. without active grabs we can't
swallow the click. I'm sure there much more...
- - Port Qt? There's already talk about this on the list.
-
- - X on Wayland
-
- - move most of the code from xf86-video-intel into a Xorg wayland
- module.
+ - dnd, copy-paste
- - don't ask KMS for available output and modes, use the info from
- the wayland server. then stop mooching off of drmmode.c.
+ - Investigate DirectFB on Wayland (or is that Wayland on DirectFB?)
- - map multiple wayland input devices to MPX in Xorg.
+ - SDL port, bnf has work in progress here:
+ http://cgit.freedesktop.org/~bnf/sdl-wayland/
- - rootless; avoid allocating and setting the front buffer, draw
- window decorations in the X server (!), how to map input?
- - gnome-shell as a wayland session compositor
+Ideas
- - runs as a client of the wayland session compositor, uses
- clutter+egl on wayland
+ - A wayland settings protocol to tell clients about themes (icons,
+ cursors, widget themes), fonts details (family, hinting
+ preferences) etc. Just send all settings at connect time, send
+ updates when a setting change. Getting a little close to gconf
+ here, but could be pretty simple:
- - talks to an Xorg server as the compositing and window manager
- for that server and renders the output to a wayland surface.
- the Xorg server should be modified to take input from the system
- compositor through gnome-shell, but not allocate a front buffer.
+ interface "settings":
+ event int_value(string name, int value)
+ event string_value(string name, string value)
- - make gnome-shell itself a nested wayland server and allow native
- wayland clients to connect and can native wayland windows with
- the windows from the X server.
+ but maybe it's better to just require that clients get that from
+ somewhere else (gconf/dbus).
- - qemu as a wayland client; session surface as X case
- - qemu has too simple acceleration, so a Wayland backend like the
- SDL/VNC ones it has now is trivial.
+Crazy ideas
- - paravirt: forward wayland screen info as mmio, expose gem ioctls as mmio
+ - AF_WAYLAND - A new socket type. Eliminate compositor context
+ switch by making kernel understand enough of wayland that it can
+ forward input events as wayland events and do page flipping in
+ response to surface_attach requests:
- - mapping vmem is tricky, should try to only use ioctl (pwrite+pread)
+ - ioctl(wayland_fd, "surface_attach to object 5 should do a kms page
+ flip on ctrc 2");
- - not useful for Windows without a windows paravirt driver.
+ - what about multiple crtcs? what about frame event for other
+ clients?
- - two approaches: 1) do a toplevel qemu window, or 2) expose a
- wayland server in the guest that forwards to the host wayland
- server, ie a "remote" compositor, but with the gem buffers
- shared. could do a wl_connection directly on mmio memory, with
- head and tail pointers. use an alloc_head register to indicate
- desired data to write, if it overwrites tail, block guest. just
- a socket would be easier.
+ - forward these input devices to the client
- - moblin as a wayland compositor
+ - "scancode 124 pressed or released with scan codes 18,22 and 30
+ held down gives control back to userspace wayland.
- - clutter as a wayland compositors
+ - what about maintaining cursor position? what about pointer
+ acceleration? maybe this only works in "client cursor mode",
+ where wayland hides the cursor and only sends relative events?
+ Solves the composited cursor problem. How does X show its
+ cursor then?
- - argh, mutter
+ - Probably not worth it.
projects / profile / ivi / wayland.git / blobdiff