--- /dev/null
+#define _POSIX_C_SOURCE 200112L
+#include <getopt.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+#include <unistd.h>
+#include <wayland-server.h>
+#include <wlr/backend.h>
+#include <wlr/render/wlr_renderer.h>
+#include <wlr/types/wlr_cursor.h>
+#include <wlr/types/wlr_compositor.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_input_device.h>
+#include <wlr/types/wlr_keyboard.h>
+#include <wlr/types/wlr_matrix.h>
+#include <wlr/types/wlr_output.h>
+#include <wlr/types/wlr_output_layout.h>
+#include <wlr/types/wlr_pointer.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/types/wlr_xcursor_manager.h>
+#include <wlr/types/wlr_xdg_shell.h>
+#include <wlr/util/log.h>
+#include <xkbcommon/xkbcommon.h>
+
+/* For brevity's sake, struct members are annotated where they are used. */
+enum tinywl_cursor_mode {
+ TINYWL_CURSOR_PASSTHROUGH,
+ TINYWL_CURSOR_MOVE,
+ TINYWL_CURSOR_RESIZE,
+};
+
+struct tinywl_server {
+ struct wl_display *wl_display;
+ struct wlr_backend *backend;
+ struct wlr_renderer *renderer;
+
+ struct wlr_xdg_shell *xdg_shell;
+ struct wl_listener new_xdg_surface;
+ struct wl_list views;
+
+ struct wlr_cursor *cursor;
+ struct wlr_xcursor_manager *cursor_mgr;
+ struct wl_listener cursor_motion;
+ struct wl_listener cursor_motion_absolute;
+ struct wl_listener cursor_button;
+ struct wl_listener cursor_axis;
+ struct wl_listener cursor_frame;
+
+ struct wlr_seat *seat;
+ struct wl_listener new_input;
+ struct wl_listener request_cursor;
+ struct wl_list keyboards;
+ enum tinywl_cursor_mode cursor_mode;
+ struct tinywl_view *grabbed_view;
+ double grab_x, grab_y;
+ int grab_width, grab_height;
+ uint32_t resize_edges;
+
+ struct wlr_output_layout *output_layout;
+ struct wl_list outputs;
+ struct wl_listener new_output;
+};
+
+struct tinywl_output {
+ struct wl_list link;
+ struct tinywl_server *server;
+ struct wlr_output *wlr_output;
+ struct wl_listener frame;
+};
+
+struct tinywl_view {
+ struct wl_list link;
+ struct tinywl_server *server;
+ struct wlr_xdg_surface *xdg_surface;
+ struct wl_listener map;
+ struct wl_listener unmap;
+ struct wl_listener destroy;
+ struct wl_listener request_move;
+ struct wl_listener request_resize;
+ bool mapped;
+ int x, y;
+};
+
+struct tinywl_keyboard {
+ struct wl_list link;
+ struct tinywl_server *server;
+ struct wlr_input_device *device;
+
+ struct wl_listener modifiers;
+ struct wl_listener key;
+};
+
+static void focus_view(struct tinywl_view *view, struct wlr_surface *surface) {
+ /* Note: this function only deals with keyboard focus. */
+ if (view == NULL) {
+ return;
+ }
+ struct tinywl_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 */
+ 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) {
+ /* This event is raised when a modifier key, such as shift or alt, is
+ * pressed. We simply communicate this to the client. */
+ struct tinywl_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 tinywl_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 tinywl_view *current_view = wl_container_of(
+ server->views.next, current_view, link);
+ struct tinywl_view *next_view = wl_container_of(
+ current_view->link.next, next_view, link);
+ focus_view(next_view, next_view->xdg_surface->surface);
+ /* Move the previous view to the end of the list */
+ wl_list_remove(¤t_view->link);
+ wl_list_insert(server->views.prev, ¤t_view->link);
+ 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 tinywl_keyboard *keyboard =
+ wl_container_of(listener, keyboard, key);
+ struct tinywl_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 == WLR_KEY_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 tinywl_server *server,
+ struct wlr_input_device *device) {
+ struct tinywl_keyboard *keyboard =
+ calloc(1, sizeof(struct tinywl_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_rule_names rules = { 0 };
+ struct xkb_context *context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
+ struct xkb_keymap *keymap = xkb_map_new_from_names(context, &rules,
+ 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 tinywl_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 tinywl_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 TinyWL 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 tinywl_server *server = wl_container_of(
+ listener, server, request_cursor);
+ /* This event is rasied 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 bool view_at(struct tinywl_view *view,
+ double lx, double ly, struct wlr_surface **surface,
+ double *sx, double *sy) {
+ /*
+ * XDG toplevels may have nested surfaces, such as popup windows for context
+ * menus or tooltips. This function tests if any of those are underneath the
+ * coordinates lx and ly (in output Layout Coordinates). If so, it sets the
+ * surface pointer to that wlr_surface and the sx and sy coordinates to the
+ * coordinates relative to that surface's top-left corner.
+ */
+ double view_sx = lx - view->x;
+ double view_sy = ly - view->y;
+
+ struct wlr_surface_state *state = &view->xdg_surface->surface->current;
+
+ double _sx, _sy;
+ struct wlr_surface *_surface = NULL;
+ _surface = wlr_xdg_surface_surface_at(
+ view->xdg_surface, view_sx, view_sy, &_sx, &_sy);
+
+ if (_surface != NULL) {
+ *sx = _sx;
+ *sy = _sy;
+ *surface = _surface;
+ return true;
+ }
+
+ return false;
+}
+
+static struct tinywl_view *desktop_view_at(
+ struct tinywl_server *server, double lx, double ly,
+ struct wlr_surface **surface, double *sx, double *sy) {
+ /* This iterates over all of our surfaces and attempts to find one under the
+ * cursor. This relies on server->views being ordered from top-to-bottom. */
+ struct tinywl_view *view;
+ wl_list_for_each(view, &server->views, link) {
+ if (view_at(view, lx, ly, surface, sx, sy)) {
+ return view;
+ }
+ }
+ return NULL;
+}
+
+static void process_cursor_move(struct tinywl_server *server, uint32_t time) {
+ /* Move the grabbed view to the new position. */
+ server->grabbed_view->x = server->cursor->x - server->grab_x;
+ server->grabbed_view->y = server->cursor->y - server->grab_y;
+}
+
+static void process_cursor_resize(struct tinywl_server *server, uint32_t 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 tinywl_view *view = server->grabbed_view;
+ double dx = server->cursor->x - server->grab_x;
+ double dy = server->cursor->y - server->grab_y;
+ double x = view->x;
+ double y = view->y;
+ int width = server->grab_width;
+ int height = server->grab_height;
+ if (server->resize_edges & WLR_EDGE_TOP) {
+ y = server->grab_y + dy;
+ height -= dy;
+ if (height < 1) {
+ y += height;
+ }
+ } else if (server->resize_edges & WLR_EDGE_BOTTOM) {
+ height += dy;
+ }
+ if (server->resize_edges & WLR_EDGE_LEFT) {
+ x = server->grab_x + dx;
+ width -= dx;
+ if (width < 1) {
+ x += width;
+ }
+ } else if (server->resize_edges & WLR_EDGE_RIGHT) {
+ width += dx;
+ }
+ view->x = x;
+ view->y = y;
+ wlr_xdg_toplevel_set_size(view->xdg_surface, width, height);
+}
+
+static void process_cursor_motion(struct tinywl_server *server, uint32_t time) {
+ /* If the mode is non-passthrough, delegate to those functions. */
+ if (server->cursor_mode == TINYWL_CURSOR_MOVE) {
+ process_cursor_move(server, time);
+ return;
+ } else if (server->cursor_mode == TINYWL_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 tinywl_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) {
+ bool focus_changed = seat->pointer_state.focused_surface != surface;
+ /*
+ * "Enter" the surface if necessary. This lets the client know that the
+ * cursor has entered one of its surfaces.
+ *
+ * Note that this gives the surface "pointer focus", which is distinct
+ * from keyboard focus. You get pointer focus by moving the pointer over
+ * a window.
+ */
+ wlr_seat_pointer_notify_enter(seat, surface, sx, sy);
+ if (!focus_changed) {
+ /* The enter event contains coordinates, so we only need to notify
+ * on motion if the focus did not change. */
+ 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 tinywl_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 tinywl_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 tinywl_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_seat *seat = server->seat;
+ struct wlr_surface *surface;
+ struct tinywl_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 = TINYWL_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 tinywl_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) {
+ /* 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 tinywl_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);
+}
+
+/* Used to move all of the data necessary to render a surface from the top-level
+ * frame handler to the per-surface render function. */
+struct render_data {
+ struct wlr_output *output;
+ struct wlr_renderer *renderer;
+ struct tinywl_view *view;
+ struct timespec *when;
+};
+
+static void render_surface(struct wlr_surface *surface,
+ int sx, int sy, void *data) {
+ /* This function is called for every surface that needs to be rendered. */
+ struct render_data *rdata = data;
+ struct tinywl_view *view = rdata->view;
+ struct wlr_output *output = rdata->output;
+
+ /* We first obtain a wlr_texture, which is a GPU resource. wlroots
+ * automatically handles negotiating these with the client. The underlying
+ * resource could be an opaque handle passed from the client, or the client
+ * could have sent a pixel buffer which we copied to the GPU, or a few other
+ * means. You don't have to worry about this, wlroots takes care of it. */
+ struct wlr_texture *texture = wlr_surface_get_texture(surface);
+ if (texture == NULL) {
+ return;
+ }
+
+ /* The view has a position in layout coordinates. If you have two displays,
+ * one next to the other, both 1080p, a view on the rightmost display might
+ * have layout coordinates of 2000,100. We need to translate that to
+ * output-local coordinates, or (2000 - 1920). */
+ double ox = 0, oy = 0;
+ wlr_output_layout_output_coords(
+ view->server->output_layout, output, &ox, &oy);
+ ox += view->x + sx, oy += view->y + sy;
+
+ /* We also have to apply the scale factor for HiDPI outputs. This is only
+ * part of the puzzle, TinyWL does not fully support HiDPI. */
+ struct wlr_box box = {
+ .x = ox * output->scale,
+ .y = oy * output->scale,
+ .width = surface->current.width * output->scale,
+ .height = surface->current.height * output->scale,
+ };
+
+ /*
+ * Those familiar with OpenGL are also familiar with the role of matricies
+ * in graphics programming. We need to prepare a matrix to render the view
+ * with. wlr_matrix_project_box is a helper which takes a box with a desired
+ * x, y coordinates, width and height, and an output geometry, then
+ * prepares an orthographic projection and multiplies the necessary
+ * transforms to produce a model-view-projection matrix.
+ *
+ * Naturally you can do this any way you like, for example to make a 3D
+ * compositor.
+ */
+ float matrix[9];
+ enum wl_output_transform transform =
+ wlr_output_transform_invert(surface->current.transform);
+ wlr_matrix_project_box(matrix, &box, transform, 0,
+ output->transform_matrix);
+
+ /* This takes our matrix, the texture, and an alpha, and performs the actual
+ * rendering on the GPU. */
+ wlr_render_texture_with_matrix(rdata->renderer, texture, matrix, 1);
+
+ /* This lets the client know that we've displayed that frame and it can
+ * prepare another one now if it likes. */
+ wlr_surface_send_frame_done(surface, rdata->when);
+}
+
+static void output_frame(struct wl_listener *listener, 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 tinywl_output *output =
+ wl_container_of(listener, output, frame);
+ struct wlr_renderer *renderer = output->server->renderer;
+
+ struct timespec now;
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ /* wlr_output_attach_render makes the OpenGL context current. */
+ if (!wlr_output_attach_render(output->wlr_output, NULL)) {
+ return;
+ }
+ /* The "effective" resolution can change if you rotate your outputs. */
+ int width, height;
+ wlr_output_effective_resolution(output->wlr_output, &width, &height);
+ /* Begin the renderer (calls glViewport and some other GL sanity checks) */
+ wlr_renderer_begin(renderer, width, height);
+
+ float color[4] = {0.3, 0.3, 0.3, 1.0};
+ wlr_renderer_clear(renderer, color);
+
+ /* Each subsequent window we render is rendered on top of the last. Because
+ * our view list is ordered front-to-back, we iterate over it backwards. */
+ struct tinywl_view *view;
+ wl_list_for_each_reverse(view, &output->server->views, link) {
+ if (!view->mapped) {
+ /* An unmapped view should not be rendered. */
+ continue;
+ }
+ struct render_data rdata = {
+ .output = output->wlr_output,
+ .view = view,
+ .renderer = renderer,
+ .when = &now,
+ };
+ /* This calls our render_surface function for each surface among the
+ * xdg_surface's toplevel and popups. */
+ wlr_xdg_surface_for_each_surface(view->xdg_surface,
+ render_surface, &rdata);
+ }
+
+ /* Hardware cursors are rendered by the GPU on a separate plane, and can be
+ * moved around without re-rendering what's beneath them - which is more
+ * efficient. However, not all hardware supports hardware cursors. For this
+ * reason, wlroots provides a software fallback, which we ask it to render
+ * here. wlr_cursor handles configuring hardware vs software cursors for you,
+ * and this function is a no-op when hardware cursors are in use. */
+ wlr_output_render_software_cursors(output->wlr_output, NULL);
+
+ /* Conclude rendering and swap the buffers, showing the final frame
+ * on-screen. */
+ wlr_renderer_end(renderer);
+ wlr_output_commit(output->wlr_output);
+}
+
+static void server_new_output(struct wl_listener *listener, void *data) {
+ /* This event is rasied by the backend when a new output (aka a display or
+ * monitor) becomes available. */
+ struct tinywl_server *server =
+ wl_container_of(listener, server, new_output);
+ struct wlr_output *wlr_output = data;
+
+ /* 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 first, a more sophisticated compositor would let the user
+ * configure it or pick the mode the display advertises as preferred. */
+ if (!wl_list_empty(&wlr_output->modes)) {
+ struct wlr_output_mode *mode =
+ wl_container_of(wlr_output->modes.prev, mode, link);
+ wlr_output_set_mode(wlr_output, mode);
+ }
+
+ /* Allocates and configures our state for this output */
+ struct tinywl_output *output =
+ calloc(1, sizeof(struct tinywl_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. */
+ wlr_output_layout_add_auto(server->output_layout, wlr_output);
+
+ /* Creating the global 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_create_global(wlr_output);
+}
+
+static void xdg_surface_map(struct wl_listener *listener, void *data) {
+ /* Called when the surface is mapped, or ready to display on-screen. */
+ struct tinywl_view *view = wl_container_of(listener, view, map);
+ view->mapped = true;
+ focus_view(view, view->xdg_surface->surface);
+}
+
+static void xdg_surface_unmap(struct wl_listener *listener, void *data) {
+ /* Called when the surface is unmapped, and should no longer be shown. */
+ struct tinywl_view *view = wl_container_of(listener, view, unmap);
+ view->mapped = false;
+}
+
+static void xdg_surface_destroy(struct wl_listener *listener, void *data) {
+ /* Called when the surface is destroyed and should never be shown again. */
+ struct tinywl_view *view = wl_container_of(listener, view, destroy);
+ wl_list_remove(&view->link);
+ free(view);
+}
+
+static void begin_interactive(struct tinywl_view *view,
+ enum tinywl_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 tinywl_server *server = view->server;
+ struct wlr_surface *focused_surface =
+ server->seat->pointer_state.focused_surface;
+ if (view->xdg_surface->surface != focused_surface) {
+ /* Deny move/resize requests from unfocused clients. */
+ return;
+ }
+ server->grabbed_view = view;
+ server->cursor_mode = mode;
+ struct wlr_box geo_box;
+ wlr_xdg_surface_get_geometry(view->xdg_surface, &geo_box);
+ if (mode == TINYWL_CURSOR_MOVE) {
+ server->grab_x = server->cursor->x - view->x;
+ server->grab_y = server->cursor->y - view->y;
+ } else {
+ server->grab_x = server->cursor->x + geo_box.x;
+ server->grab_y = server->cursor->y + geo_box.y;
+ }
+ server->grab_width = geo_box.width;
+ server->grab_height = geo_box.height;
+ server->resize_edges = edges;
+}
+
+static void xdg_toplevel_request_move(
+ struct wl_listener *listener, 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
+ * provied serial against a list of button press serials sent to this
+ * client, to prevent the client from requesting this whenever they want. */
+ struct tinywl_view *view = wl_container_of(listener, view, request_move);
+ begin_interactive(view, TINYWL_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
+ * provied 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 tinywl_view *view = wl_container_of(listener, view, request_resize);
+ begin_interactive(view, TINYWL_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 tinywl_server *server =
+ wl_container_of(listener, server, new_xdg_surface);
+ struct wlr_xdg_surface *xdg_surface = data;
+ if (xdg_surface->role != WLR_XDG_SURFACE_ROLE_TOPLEVEL) {
+ return;
+ }
+
+ /* Allocate a tinywl_view for this surface */
+ struct tinywl_view *view =
+ calloc(1, sizeof(struct tinywl_view));
+ view->server = server;
+ view->xdg_surface = xdg_surface;
+
+ /* Listen to the various events it can emit */
+ view->map.notify = xdg_surface_map;
+ wl_signal_add(&xdg_surface->events.map, &view->map);
+ view->unmap.notify = xdg_surface_unmap;
+ wl_signal_add(&xdg_surface->events.unmap, &view->unmap);
+ view->destroy.notify = xdg_surface_destroy;
+ 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);
+
+ /* Add it to the list of views. */
+ wl_list_insert(&server->views, &view->link);
+}
+
+int main(int argc, char *argv[]) {
+ wlr_log_init(WLR_DEBUG, NULL);
+ char *startup_cmd = NULL;
+
+ int c;
+ while ((c = getopt(argc, argv, "s:h")) != -1) {
+ switch (c) {
+ case 's':
+ startup_cmd = optarg;
+ break;
+ default:
+ printf("Usage: %s [-s startup command]\n", argv[0]);
+ return 0;
+ }
+ }
+ if (optind < argc) {
+ printf("Usage: %s [-s startup command]\n", argv[0]);
+ return 0;
+ }
+
+ struct tinywl_server server;
+ /* 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. The NULL argument here optionally allows you
+ * to pass in a custom renderer if wlr_renderer doesn't meet your needs. The
+ * backend uses the renderer, for example, to fall back to software cursors
+ * if the backend does not support hardware cursors (some older GPUs
+ * don't). */
+ server.backend = wlr_backend_autocreate(server.wl_display, NULL);
+
+ /* If we don't provide a renderer, autocreate makes a GLES2 renderer for us.
+ * The renderer is responsible for defining the various pixel formats it
+ * supports for shared memory, this configures that for clients. */
+ server.renderer = wlr_backend_get_renderer(server.backend);
+ wlr_renderer_init_wl_display(server.renderer, server.wl_display);
+
+ /* 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. */
+ 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);
+
+ /* Set up our list of views and 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);
+
+ /* 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);
+ 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);
+ return 1;
+ }
+
+ /* Set the WAYLAND_DISPLAY environment variable to our socket and run the
+ * startup command if requested. */
+ setenv("WAYLAND_DISPLAY", socket, true);
+ if (startup_cmd) {
+ if (fork() == 0) {
+ execl("/bin/sh", "/bin/sh", "-c", startup_cmd, (void *)NULL);
+ }
+ }
+ /* 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. */
+ wlr_log(WLR_INFO, "Running Wayland compositor on WAYLAND_DISPLAY=%s",
+ socket);
+ wl_display_run(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);
+ return 0;
+}
projects / proto / labwc.git / commitdiff