/* * Feynman -- Wayland compositor for GNU Emacs * * Copyright (c) 2022 Sameer Rahmani * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include "compositor.h" #include "utils.h" #include #include #include #include #include #include static void /* cppcheck-suppress constParameter */ focus_view (struct feynman_view *view, struct wlr_surface *surface) { /* Note: this function only deals with keyboard focus. */ if (view == NULL) { return; } struct feynman_server *server = view->server; struct wlr_seat *seat = server->seat; struct wlr_surface *prev_surface = seat->keyboard_state.focused_surface; if (prev_surface == surface) { /* Don't re-focus an already focused surface. */ return; } if (prev_surface) { /* * Deactivate the previously focused surface. This lets the client know * it no longer has focus and the client will repaint accordingly, e.g. * stop displaying a caret. */ struct wlr_xdg_surface *previous = wlr_xdg_surface_from_wlr_surface ( seat->keyboard_state.focused_surface); wlr_xdg_toplevel_set_activated (previous, false); } struct wlr_keyboard *keyboard = wlr_seat_get_keyboard (seat); /* Move the view to the front */ wlr_scene_node_raise_to_top (view->scene_node); wl_list_remove (&view->link); wl_list_insert (&server->views, &view->link); /* Activate the new surface */ wlr_xdg_toplevel_set_activated (view->xdg_surface, true); /* * Tell the seat to have the keyboard enter this surface. wlroots will keep * track of this and automatically send key events to the appropriate * clients without additional work on your part. */ wlr_seat_keyboard_notify_enter (seat, view->xdg_surface->surface, keyboard->keycodes, keyboard->num_keycodes, &keyboard->modifiers); } static void keyboard_handle_modifiers (struct wl_listener *listener, void *data) { (void)data; /* This event is raised when a modifier key, such as shift or alt, is * pressed. We simply communicate this to the client. */ struct feynman_keyboard *keyboard = wl_container_of (listener, keyboard, modifiers); /* * A seat can only have one keyboard, but this is a limitation of the * Wayland protocol - not wlroots. We assign all connected keyboards to the * same seat. You can swap out the underlying wlr_keyboard like this and * wlr_seat handles this transparently. */ wlr_seat_set_keyboard (keyboard->server->seat, keyboard->device); /* Send modifiers to the client. */ wlr_seat_keyboard_notify_modifiers (keyboard->server->seat, &keyboard->device->keyboard->modifiers); } static bool handle_keybinding (struct feynman_server *server, xkb_keysym_t sym) { /* * Here we handle compositor keybindings. This is when the compositor is * processing keys, rather than passing them on to the client for its own * processing. * * This function assumes Alt is held down. */ switch (sym) { case XKB_KEY_Escape: wl_display_terminate (server->wl_display); break; case XKB_KEY_F1: /* Cycle to the next view */ if (wl_list_length (&server->views) < 2) { break; } struct feynman_view *next_view = wl_container_of (server->views.prev, next_view, link); focus_view (next_view, next_view->xdg_surface->surface); break; default: return false; } return true; } static void keyboard_handle_key (struct wl_listener *listener, void *data) { /* This event is raised when a key is pressed or released. */ struct feynman_keyboard *keyboard = wl_container_of (listener, keyboard, key); struct feynman_server *server = keyboard->server; struct wlr_event_keyboard_key *event = data; struct wlr_seat *seat = server->seat; /* Translate libinput keycode -> xkbcommon */ uint32_t keycode = event->keycode + 8; /* Get a list of keysyms based on the keymap for this keyboard */ const xkb_keysym_t *syms; int nsyms = xkb_state_key_get_syms (keyboard->device->keyboard->xkb_state, keycode, &syms); bool handled = false; uint32_t modifiers = wlr_keyboard_get_modifiers (keyboard->device->keyboard); if ((modifiers & WLR_MODIFIER_ALT) && event->state == WL_KEYBOARD_KEY_STATE_PRESSED) { /* If alt is held down and this button was _pressed_, we attempt to * process it as a compositor keybinding. */ for (int i = 0; i < nsyms; i++) { handled = handle_keybinding (server, syms[i]); } } if (!handled) { /* Otherwise, we pass it along to the client. */ wlr_seat_set_keyboard (seat, keyboard->device); wlr_seat_keyboard_notify_key (seat, event->time_msec, event->keycode, event->state); } } static void server_new_keyboard (struct feynman_server *server, struct wlr_input_device *device) { struct feynman_keyboard *keyboard = calloc (1, sizeof (struct feynman_keyboard)); keyboard->server = server; keyboard->device = device; /* We need to prepare an XKB keymap and assign it to the keyboard. This * assumes the defaults (e.g. layout = "us"). */ struct xkb_context *context = xkb_context_new (XKB_CONTEXT_NO_FLAGS); struct xkb_keymap *keymap = xkb_keymap_new_from_names (context, NULL, XKB_KEYMAP_COMPILE_NO_FLAGS); wlr_keyboard_set_keymap (device->keyboard, keymap); xkb_keymap_unref (keymap); xkb_context_unref (context); wlr_keyboard_set_repeat_info (device->keyboard, 25, 600); /* Here we set up listeners for keyboard events. */ keyboard->modifiers.notify = keyboard_handle_modifiers; wl_signal_add (&device->keyboard->events.modifiers, &keyboard->modifiers); keyboard->key.notify = keyboard_handle_key; wl_signal_add (&device->keyboard->events.key, &keyboard->key); wlr_seat_set_keyboard (server->seat, device); /* And add the keyboard to our list of keyboards */ wl_list_insert (&server->keyboards, &keyboard->link); } static void server_new_pointer (struct feynman_server *server, struct wlr_input_device *device) { /* We don't do anything special with pointers. All of our pointer handling * is proxied through wlr_cursor. On another compositor, you might take this * opportunity to do libinput configuration on the device to set * acceleration, etc. */ wlr_cursor_attach_input_device (server->cursor, device); } static void server_new_input (struct wl_listener *listener, void *data) { /* This event is raised by the backend when a new input device becomes * available. */ struct feynman_server *server = wl_container_of (listener, server, new_input); struct wlr_input_device *device = data; switch (device->type) { case WLR_INPUT_DEVICE_KEYBOARD: server_new_keyboard (server, device); break; case WLR_INPUT_DEVICE_POINTER: server_new_pointer (server, device); break; default: break; } /* We need to let the wlr_seat know what our capabilities are, which is * communiciated to the client. In Feynman we always have a cursor, even if * there are no pointer devices, so we always include that capability. */ uint32_t caps = WL_SEAT_CAPABILITY_POINTER; if (!wl_list_empty (&server->keyboards)) { caps |= WL_SEAT_CAPABILITY_KEYBOARD; } wlr_seat_set_capabilities (server->seat, caps); } static void seat_request_cursor (struct wl_listener *listener, void *data) { struct feynman_server *server = wl_container_of (listener, server, request_cursor); /* This event is raised by the seat when a client provides a cursor image */ struct wlr_seat_pointer_request_set_cursor_event *event = data; struct wlr_seat_client *focused_client = server->seat->pointer_state.focused_client; /* This can be sent by any client, so we check to make sure this one is * actually has pointer focus first. */ if (focused_client == event->seat_client) { /* Once we've vetted the client, we can tell the cursor to use the * provided surface as the cursor image. It will set the hardware cursor * on the output that it's currently on and continue to do so as the * cursor moves between outputs. */ wlr_cursor_set_surface (server->cursor, event->surface, event->hotspot_x, event->hotspot_y); } } static void seat_request_set_selection (struct wl_listener *listener, void *data) { /* This event is raised by the seat when a client wants to set the selection, * usually when the user copies something. wlroots allows compositors to * ignore such requests if they so choose, but in feynman we always honor */ struct feynman_server *server = wl_container_of (listener, server, request_set_selection); struct wlr_seat_request_set_selection_event *event = data; wlr_seat_set_selection (server->seat, event->source, event->serial); } static struct feynman_view * desktop_view_at (struct feynman_server *server, double lx, double ly, struct wlr_surface **surface, double *sx, double *sy) { /* This returns the topmost node in the scene at the given layout coords. * we only care about surface nodes as we are specifically looking for a * surface in the surface tree of a feynman_view. */ struct wlr_scene_node *node = wlr_scene_node_at (&server->scene->node, lx, ly, sx, sy); if (node == NULL || node->type != WLR_SCENE_NODE_SURFACE) { return NULL; } *surface = wlr_scene_surface_from_node (node)->surface; /* Find the node corresponding to the feynman_view at the root of this * surface tree, it is the only one for which we set the data field. */ while (node != NULL && node->data == NULL) { node = node->parent; } /* cppcheck-suppress nullPointerRedundantCheck */ return node->data; } static void process_cursor_move (struct feynman_server *server, uint32_t time) { (void)time; /* Move the grabbed view to the new position. */ struct feynman_view *view = server->grabbed_view; view->x = server->cursor->x - server->grab_x; view->y = server->cursor->y - server->grab_y; wlr_scene_node_set_position (view->scene_node, view->x, view->y); } static void process_cursor_resize (struct feynman_server *server, uint32_t time) { (void)time; /* * Resizing the grabbed view can be a little bit complicated, because we * could be resizing from any corner or edge. This not only resizes the view * on one or two axes, but can also move the view if you resize from the top * or left edges (or top-left corner). * * Note that I took some shortcuts here. In a more fleshed-out compositor, * you'd wait for the client to prepare a buffer at the new size, then * commit any movement that was prepared. */ struct feynman_view *view = server->grabbed_view; double border_x = server->cursor->x - server->grab_x; double border_y = server->cursor->y - server->grab_y; int new_left = server->grab_geobox.x; int new_right = server->grab_geobox.x + server->grab_geobox.width; int new_top = server->grab_geobox.y; int new_bottom = server->grab_geobox.y + server->grab_geobox.height; if (server->resize_edges & WLR_EDGE_TOP) { new_top = border_y; if (new_top >= new_bottom) { new_top = new_bottom - 1; } } else if (server->resize_edges & WLR_EDGE_BOTTOM) { new_bottom = border_y; if (new_bottom <= new_top) { new_bottom = new_top + 1; } } if (server->resize_edges & WLR_EDGE_LEFT) { new_left = border_x; if (new_left >= new_right) { new_left = new_right - 1; } } else if (server->resize_edges & WLR_EDGE_RIGHT) { new_right = border_x; if (new_right <= new_left) { new_right = new_left + 1; } } struct wlr_box geo_box; wlr_xdg_surface_get_geometry (view->xdg_surface, &geo_box); view->x = new_left - geo_box.x; view->y = new_top - geo_box.y; wlr_scene_node_set_position (view->scene_node, view->x, view->y); int new_width = new_right - new_left; int new_height = new_bottom - new_top; wlr_xdg_toplevel_set_size (view->xdg_surface, new_width, new_height); } static void process_cursor_motion (struct feynman_server *server, uint32_t time) { /* If the mode is non-passthrough, delegate to those functions. */ if (server->cursor_mode == FEYNMAN_CURSOR_MOVE) { process_cursor_move (server, time); return; } else if (server->cursor_mode == FEYNMAN_CURSOR_RESIZE) { process_cursor_resize (server, time); return; } /* Otherwise, find the view under the pointer and send the event along. */ double sx, sy; struct wlr_seat *seat = server->seat; struct wlr_surface *surface = NULL; struct feynman_view *view = desktop_view_at ( server, server->cursor->x, server->cursor->y, &surface, &sx, &sy); if (!view) { /* If there's no view under the cursor, set the cursor image to a * default. This is what makes the cursor image appear when you move it * around the screen, not over any views. */ wlr_xcursor_manager_set_cursor_image (server->cursor_mgr, "left_ptr", server->cursor); } if (surface) { /* * Send pointer enter and motion events. * * The enter event gives the surface "pointer focus", which is distinct * from keyboard focus. You get pointer focus by moving the pointer over * a window. * * Note that wlroots will avoid sending duplicate enter/motion events if * the surface has already has pointer focus or if the client is already * aware of the coordinates passed. */ wlr_seat_pointer_notify_enter (seat, surface, sx, sy); wlr_seat_pointer_notify_motion (seat, time, sx, sy); } else { /* Clear pointer focus so future button events and such are not sent to * the last client to have the cursor over it. */ wlr_seat_pointer_clear_focus (seat); } } static void server_cursor_motion (struct wl_listener *listener, void *data) { /* This event is forwarded by the cursor when a pointer emits a _relative_ * pointer motion event (i.e. a delta) */ struct feynman_server *server = wl_container_of (listener, server, cursor_motion); struct wlr_event_pointer_motion *event = data; /* The cursor doesn't move unless we tell it to. The cursor automatically * handles constraining the motion to the output layout, as well as any * special configuration applied for the specific input device which * generated the event. You can pass NULL for the device if you want to move * the cursor around without any input. */ wlr_cursor_move (server->cursor, event->device, event->delta_x, event->delta_y); process_cursor_motion (server, event->time_msec); } static void server_cursor_motion_absolute (struct wl_listener *listener, void *data) { /* This event is forwarded by the cursor when a pointer emits an _absolute_ * motion event, from 0..1 on each axis. This happens, for example, when * wlroots is running under a Wayland window rather than KMS+DRM, and you * move the mouse over the window. You could enter the window from any edge, * so we have to warp the mouse there. There is also some hardware which * emits these events. */ struct feynman_server *server = wl_container_of (listener, server, cursor_motion_absolute); struct wlr_event_pointer_motion_absolute *event = data; wlr_cursor_warp_absolute (server->cursor, event->device, event->x, event->y); process_cursor_motion (server, event->time_msec); } static void server_cursor_button (struct wl_listener *listener, void *data) { /* This event is forwarded by the cursor when a pointer emits a button * event. */ struct feynman_server *server = wl_container_of (listener, server, cursor_button); struct wlr_event_pointer_button *event = data; /* Notify the client with pointer focus that a button press has occurred */ wlr_seat_pointer_notify_button (server->seat, event->time_msec, event->button, event->state); double sx, sy; struct wlr_surface *surface = NULL; struct feynman_view *view = desktop_view_at ( server, server->cursor->x, server->cursor->y, &surface, &sx, &sy); if (event->state == WLR_BUTTON_RELEASED) { /* If you released any buttons, we exit interactive move/resize mode. */ server->cursor_mode = FEYNMAN_CURSOR_PASSTHROUGH; } else { /* Focus that client if the button was _pressed_ */ focus_view (view, surface); } } static void server_cursor_axis (struct wl_listener *listener, void *data) { /* This event is forwarded by the cursor when a pointer emits an axis event, * for example when you move the scroll wheel. */ struct feynman_server *server = wl_container_of (listener, server, cursor_axis); struct wlr_event_pointer_axis *event = data; /* Notify the client with pointer focus of the axis event. */ wlr_seat_pointer_notify_axis (server->seat, event->time_msec, event->orientation, event->delta, event->delta_discrete, event->source); } static void server_cursor_frame (struct wl_listener *listener, void *data) { (void)data; /* This event is forwarded by the cursor when a pointer emits an frame * event. Frame events are sent after regular pointer events to group * multiple events together. For instance, two axis events may happen at the * same time, in which case a frame event won't be sent in between. */ struct feynman_server *server = wl_container_of (listener, server, cursor_frame); /* Notify the client with pointer focus of the frame event. */ wlr_seat_pointer_notify_frame (server->seat); } static void output_frame (struct wl_listener *listener, void *data) { (void)data; /* This function is called every time an output is ready to display a frame, * generally at the output's refresh rate (e.g. 60Hz). */ struct feynman_output *output = wl_container_of (listener, output, frame); struct wlr_scene *scene = output->server->scene; struct wlr_scene_output *scene_output = wlr_scene_get_scene_output (scene, output->wlr_output); /* Render the scene if needed and commit the output */ wlr_scene_output_commit (scene_output); struct timespec now; clock_gettime (CLOCK_MONOTONIC, &now); wlr_scene_output_send_frame_done (scene_output, &now); } static void server_new_output (struct wl_listener *listener, void *data) { /* This event is raised by the backend when a new output (aka a display or * monitor) becomes available. */ struct feynman_server *server = wl_container_of (listener, server, new_output); struct wlr_output *wlr_output = data; /* Configures the output created by the backend to use our allocator * and our renderer. Must be done once, before commiting the output */ wlr_output_init_render (wlr_output, server->allocator, server->renderer); /* Some backends don't have modes. DRM+KMS does, and we need to set a mode * before we can use the output. The mode is a tuple of (width, height, * refresh rate), and each monitor supports only a specific set of modes. We * just pick the monitor's preferred mode, a more sophisticated compositor * would let the user configure it. */ if (!wl_list_empty (&wlr_output->modes)) { struct wlr_output_mode *mode = wlr_output_preferred_mode (wlr_output); wlr_output_set_mode (wlr_output, mode); wlr_output_enable (wlr_output, true); if (!wlr_output_commit (wlr_output)) { return; } } /* Allocates and configures our state for this output */ struct feynman_output *output = calloc (1, sizeof (struct feynman_output)); output->wlr_output = wlr_output; output->server = server; /* Sets up a listener for the frame notify event. */ output->frame.notify = output_frame; wl_signal_add (&wlr_output->events.frame, &output->frame); wl_list_insert (&server->outputs, &output->link); /* Adds this to the output layout. The add_auto function arranges outputs * from left-to-right in the order they appear. A more sophisticated * compositor would let the user configure the arrangement of outputs in the * layout. * * The output layout utility automatically adds a wl_output global to the * display, which Wayland clients can see to find out information about the * output (such as DPI, scale factor, manufacturer, etc). */ wlr_output_layout_add_auto (server->output_layout, wlr_output); } static void xdg_toplevel_map (struct wl_listener *listener, void *data) { (void)data; /* Called when the surface is mapped, or ready to display on-screen. */ struct feynman_view *view = wl_container_of (listener, view, map); wl_list_insert (&view->server->views, &view->link); focus_view (view, view->xdg_surface->surface); } static void xdg_toplevel_unmap (struct wl_listener *listener, void *data) { (void)data; /* Called when the surface is unmapped, and should no longer be shown. */ struct feynman_view *view = wl_container_of (listener, view, unmap); wl_list_remove (&view->link); } static void xdg_toplevel_handler (struct wl_listener *listener, void *data) { (void)data; /* Called when the surface is destroyed and should never be shown again. */ struct feynman_view *view = wl_container_of (listener, view, destroy); wl_list_remove (&view->map.link); wl_list_remove (&view->unmap.link); wl_list_remove (&view->destroy.link); wl_list_remove (&view->request_move.link); wl_list_remove (&view->request_resize.link); free (view); } static void begin_interactive (struct feynman_view *view, enum feynman_cursor_mode mode, uint32_t edges) { /* This function sets up an interactive move or resize operation, where the * compositor stops propegating pointer events to clients and instead * consumes them itself, to move or resize windows. */ struct feynman_server *server = view->server; struct wlr_surface *focused_surface = server->seat->pointer_state.focused_surface; if (view->xdg_surface->surface != wlr_surface_get_root_surface (focused_surface)) { /* Deny move/resize requests from unfocused clients. */ return; } server->grabbed_view = view; server->cursor_mode = mode; if (mode == FEYNMAN_CURSOR_MOVE) { server->grab_x = server->cursor->x - view->x; server->grab_y = server->cursor->y - view->y; } else { struct wlr_box geo_box; wlr_xdg_surface_get_geometry (view->xdg_surface, &geo_box); double border_x = (view->x + geo_box.x) + ((edges & WLR_EDGE_RIGHT) ? geo_box.width : 0); double border_y = (view->y + geo_box.y) + ((edges & WLR_EDGE_BOTTOM) ? geo_box.height : 0); server->grab_x = server->cursor->x - border_x; server->grab_y = server->cursor->y - border_y; server->grab_geobox = geo_box; server->grab_geobox.x += view->x; server->grab_geobox.y += view->y; server->resize_edges = edges; } } static void xdg_toplevel_request_move (struct wl_listener *listener, void *data) { (void)data; /* This event is raised when a client would like to begin an interactive * move, typically because the user clicked on their client-side * decorations. Note that a more sophisticated compositor should check the * provided serial against a list of button press serials sent to this * client, to prevent the client from requesting this whenever they want. */ struct feynman_view *view = wl_container_of (listener, view, request_move); begin_interactive (view, FEYNMAN_CURSOR_MOVE, 0); } static void xdg_toplevel_request_resize (struct wl_listener *listener, void *data) { /* This event is raised when a client would like to begin an interactive * resize, typically because the user clicked on their client-side * decorations. Note that a more sophisticated compositor should check the * provided serial against a list of button press serials sent to this * client, to prevent the client from requesting this whenever they want. */ struct wlr_xdg_toplevel_resize_event *event = data; struct feynman_view *view = wl_container_of (listener, view, request_resize); begin_interactive (view, FEYNMAN_CURSOR_RESIZE, event->edges); } static void server_new_xdg_surface (struct wl_listener *listener, void *data) { /* This event is raised when wlr_xdg_shell receives a new xdg surface from a * client, either a toplevel (application window) or popup. */ struct feynman_server *server = wl_container_of (listener, server, new_xdg_surface); struct wlr_xdg_surface *xdg_surface = data; /* We must add xdg popups to the scene graph so they get rendered. The * wlroots scene graph provides a helper for this, but to use it we must * provide the proper parent scene node of the xdg popup. To enable this, * we always set the user data field of xdg_surfaces to the corresponding * scene node. */ if (xdg_surface->role == WLR_XDG_SURFACE_ROLE_POPUP) { struct wlr_xdg_surface *parent = wlr_xdg_surface_from_wlr_surface (xdg_surface->popup->parent); struct wlr_scene_node *parent_node = parent->data; xdg_surface->data = wlr_scene_xdg_surface_create (parent_node, xdg_surface); return; } assert (xdg_surface->role == WLR_XDG_SURFACE_ROLE_TOPLEVEL); /* Allocate a feynman_view for this surface */ struct feynman_view *view = calloc (1, sizeof (struct feynman_view)); view->server = server; view->xdg_surface = xdg_surface; view->scene_node = wlr_scene_xdg_surface_create (&view->server->scene->node, view->xdg_surface); view->scene_node->data = view; xdg_surface->data = view->scene_node; /* Listen to the various events it can emit */ view->map.notify = xdg_toplevel_map; wl_signal_add (&xdg_surface->events.map, &view->map); view->unmap.notify = xdg_toplevel_unmap; wl_signal_add (&xdg_surface->events.unmap, &view->unmap); view->destroy.notify = xdg_toplevel_handler; wl_signal_add (&xdg_surface->events.destroy, &view->destroy); /* cotd */ struct wlr_xdg_toplevel *toplevel = xdg_surface->toplevel; view->request_move.notify = xdg_toplevel_request_move; wl_signal_add (&toplevel->events.request_move, &view->request_move); view->request_resize.notify = xdg_toplevel_request_resize; wl_signal_add (&toplevel->events.request_resize, &view->request_resize); } int init_feynman_server (emacs_env *env, struct feynman_server *server) { wlr_log_init (WLR_DEBUG, NULL); /* The Wayland display is managed by libwayland. It handles accepting * clients from the Unix socket, manging Wayland globals, and so on. */ server->wl_display = wl_display_create (); /* The backend is a wlroots feature which abstracts the underlying input and * output hardware. The autocreate option will choose the most suitable * backend based on the current environment, such as opening an X11 window * if an X11 server is running. */ server->backend = wlr_backend_autocreate (server->wl_display); /* Autocreates a renderer, either Pixman, GLES2 or Vulkan for us. The user * can also specify a renderer using the WLR_RENDERER env var. * The renderer is responsible for defining the various pixel formats it * supports for shared memory, this configures that for clients. */ server->renderer = wlr_renderer_autocreate (server->backend); wlr_renderer_init_wl_display (server->renderer, server->wl_display); /* Autocreates an allocator for us. * The allocator is the bridge between the renderer and the backend. It * handles the buffer creation, allowing wlroots to render onto the * screen */ server->allocator = wlr_allocator_autocreate (server->backend, server->renderer); /* This creates some hands-off wlroots interfaces. The compositor is * necessary for clients to allocate surfaces and the data device manager * handles the clipboard. Each of these wlroots interfaces has room for you * to dig your fingers in and play with their behavior if you want. Note that * the clients cannot set the selection directly without compositor approval, * see the handling of the request_set_selection event below.*/ wlr_compositor_create (server->wl_display, server->renderer); wlr_data_device_manager_create (server->wl_display); /* Creates an output layout, which a wlroots utility for working with an * arrangement of screens in a physical layout. */ server->output_layout = wlr_output_layout_create (); /* Configure a listener to be notified when new outputs are available on the * backend. */ wl_list_init (&server->outputs); server->new_output.notify = server_new_output; wl_signal_add (&server->backend->events.new_output, &server->new_output); /* Create a scene graph. This is a wlroots abstraction that handles all * rendering and damage tracking. All the compositor author needs to do * is add things that should be rendered to the scene graph at the proper * positions and then call wlr_scene_output_commit() to render a frame if * necessary. */ server->scene = wlr_scene_create (); wlr_scene_attach_output_layout (server->scene, server->output_layout); /* Set up the xdg-shell. The xdg-shell is a Wayland protocol which is used * for application windows. For more detail on shells, refer to my article: * * https://drewdevault.com/2018/07/29/Wayland-shells.html */ wl_list_init (&server->views); server->xdg_shell = wlr_xdg_shell_create (server->wl_display); server->new_xdg_surface.notify = server_new_xdg_surface; wl_signal_add (&server->xdg_shell->events.new_surface, &server->new_xdg_surface); /* * Creates a cursor, which is a wlroots utility for tracking the cursor * image shown on screen. */ server->cursor = wlr_cursor_create (); wlr_cursor_attach_output_layout (server->cursor, server->output_layout); /* Creates an xcursor manager, another wlroots utility which loads up * Xcursor themes to source cursor images from and makes sure that cursor * images are available at all scale factors on the screen (necessary for * HiDPI support). We add a cursor theme at scale factor 1 to begin with. */ server->cursor_mgr = wlr_xcursor_manager_create (NULL, 24); wlr_xcursor_manager_load (server->cursor_mgr, 1); /* * wlr_cursor *only* displays an image on screen. It does not move around * when the pointer moves. However, we can attach input devices to it, and * it will generate aggregate events for all of them. In these events, we * can choose how we want to process them, forwarding them to clients and * moving the cursor around. More detail on this process is described in my * input handling blog post: * * https://drewdevault.com/2018/07/17/Input-handling-in-wlroots.html * * And more comments are sprinkled throughout the notify functions above. */ server->cursor_motion.notify = server_cursor_motion; wl_signal_add (&server->cursor->events.motion, &server->cursor_motion); server->cursor_motion_absolute.notify = server_cursor_motion_absolute; wl_signal_add (&server->cursor->events.motion_absolute, &server->cursor_motion_absolute); server->cursor_button.notify = server_cursor_button; wl_signal_add (&server->cursor->events.button, &server->cursor_button); server->cursor_axis.notify = server_cursor_axis; wl_signal_add (&server->cursor->events.axis, &server->cursor_axis); server->cursor_frame.notify = server_cursor_frame; wl_signal_add (&server->cursor->events.frame, &server->cursor_frame); /* * Configures a seat, which is a single "seat" at which a user sits and * operates the computer. This conceptually includes up to one keyboard, * pointer, touch, and drawing tablet device. We also rig up a listener to * let us know when new input devices are available on the backend. */ wl_list_init (&server->keyboards); server->new_input.notify = server_new_input; wl_signal_add (&server->backend->events.new_input, &server->new_input); server->seat = wlr_seat_create (server->wl_display, "seat0"); server->request_cursor.notify = seat_request_cursor; wl_signal_add (&server->seat->events.request_set_cursor, &server->request_cursor); server->request_set_selection.notify = seat_request_set_selection; wl_signal_add (&server->seat->events.request_set_selection, &server->request_set_selection); /* Add a Unix socket to the Wayland display. */ const char *socket = wl_display_add_socket_auto (server->wl_display); if (!socket) { wlr_backend_destroy (server->backend); em_error (env, "Failed to create a unix socket!"); return 1; } /* Start the backend. This will enumerate outputs and inputs, become the DRM * master, etc */ if (!wlr_backend_start (server->backend)) { wlr_backend_destroy (server->backend); wl_display_destroy (server->wl_display); em_error (env, "Couldn't start the backend"); return 2; } /* Set the WAYLAND_DISPLAY environment variable to our socket */ setenv ("WAYLAND_DISPLAY", socket, true); /* Run the Wayland event loop. This does not return until you exit the * compositor. Starting the backend rigged up all of the necessary event * loop configuration to listen to libinput events, DRM events, generate * frame events at the refresh rate, and so on. */ em_message (env, "Running Wayland compositor on WAYLAND_DISPLAY=%s", socket); wlr_log (WLR_INFO, "Running Wayland compositor on WAYLAND_DISPLAY=%s", socket); return 0; } void start_feynman (struct feynman_server *server) { assert (server); wl_display_run (server->wl_display); } void stop_feynman (emacs_env *env, struct feynman_server *server) { (void)env; wl_display_terminate (server->wl_display); /* Once wl_display_run returns, we shut down the server-> */ wl_display_destroy_clients (server->wl_display); wl_display_destroy (server->wl_display); }