Merge pull request #786 from emersion/x11-backend-multiple-outputs

backend/x11: add support for multiple outputs

1 files changed, 182 insertions, 0 deletions

diff --git a/backend/x11/output.c b/backend/x11/output.c
new file mode 100644
index 00000000..9e7424d8
--- /dev/null
+++ b/backend/x11/output.c
@@ -0,0 +1,182 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <wlr/interfaces/wlr_output.h>
+#include <wlr/util/log.h>
+#include "backend/x11.h"
+#include "util/signal.h"
+
+static int signal_frame(void *data) {
+	struct wlr_x11_output *output = data;
+	wlr_output_send_frame(&output->wlr_output);
+	wl_event_source_timer_update(output->frame_timer, output->frame_delay);
+	return 0;
+}
+
+static void parse_xcb_setup(struct wlr_output *output, xcb_connection_t *xcb_conn) {
+	const xcb_setup_t *xcb_setup = xcb_get_setup(xcb_conn);
+
+	snprintf(output->make, sizeof(output->make), "%.*s",
+			xcb_setup_vendor_length(xcb_setup),
+			xcb_setup_vendor(xcb_setup));
+	snprintf(output->model, sizeof(output->model), "%"PRIu16".%"PRIu16,
+			xcb_setup->protocol_major_version,
+			xcb_setup->protocol_minor_version);
+}
+
+static bool output_set_custom_mode(struct wlr_output *wlr_output, int32_t width,
+		int32_t height, int32_t refresh) {
+	struct wlr_x11_output *output = (struct wlr_x11_output *)wlr_output;
+	struct wlr_x11_backend *x11 = output->x11;
+
+	wlr_output_update_custom_mode(&output->wlr_output, wlr_output->width,
+		wlr_output->height, refresh);
+	output->frame_delay = 1000000 / refresh;
+
+	const uint32_t values[] = { width, height };
+	xcb_configure_window(x11->xcb_conn, output->win,
+		XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT, values);
+	return true;
+}
+
+static void output_transform(struct wlr_output *wlr_output,
+		enum wl_output_transform transform) {
+	struct wlr_x11_output *output = (struct wlr_x11_output *)wlr_output;
+	output->wlr_output.transform = transform;
+}
+
+static void output_destroy(struct wlr_output *wlr_output) {
+	struct wlr_x11_output *output = (struct wlr_x11_output *)wlr_output;
+	struct wlr_x11_backend *x11 = output->x11;
+
+	wl_list_remove(&output->link);
+	wl_event_source_remove(output->frame_timer);
+	eglDestroySurface(x11->egl.display, output->surf);
+	xcb_destroy_window(x11->xcb_conn, output->win);
+	free(output);
+}
+
+static bool output_make_current(struct wlr_output *wlr_output, int *buffer_age) {
+	struct wlr_x11_output *output = (struct wlr_x11_output *)wlr_output;
+	struct wlr_x11_backend *x11 = output->x11;
+
+	return wlr_egl_make_current(&x11->egl, output->surf, buffer_age);
+}
+
+static bool output_swap_buffers(struct wlr_output *wlr_output,
+		pixman_region32_t *damage) {
+	struct wlr_x11_output *output = (struct wlr_x11_output *)wlr_output;
+	struct wlr_x11_backend *x11 = output->x11;
+
+	return wlr_egl_swap_buffers(&x11->egl, output->surf, damage);
+}
+
+static const struct wlr_output_impl output_impl = {
+	.set_custom_mode = output_set_custom_mode,
+	.transform = output_transform,
+	.destroy = output_destroy,
+	.make_current = output_make_current,
+	.swap_buffers = output_swap_buffers,
+};
+
+struct wlr_output *wlr_x11_output_create(struct wlr_backend *backend) {
+	assert(wlr_backend_is_x11(backend));
+	struct wlr_x11_backend *x11 = (struct wlr_x11_backend *)backend;
+
+	if (!x11->started) {
+		++x11->requested_outputs;
+		return NULL;
+	}
+
+	struct wlr_x11_output *output = calloc(1, sizeof(struct wlr_x11_output));
+	if (output == NULL) {
+		return NULL;
+	}
+	output->x11 = x11;
+
+	struct wlr_output *wlr_output = &output->wlr_output;
+	wlr_output_init(wlr_output, &x11->backend, &output_impl, x11->wl_display);
+
+	wlr_output->refresh = 60 * 1000000;
+	output->frame_delay = 16; // 60 Hz
+
+	snprintf(wlr_output->name, sizeof(wlr_output->name), "X11-%d",
+		wl_list_length(&x11->outputs) + 1);
+	parse_xcb_setup(wlr_output, x11->xcb_conn);
+
+	uint32_t mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+	uint32_t values[2] = {
+		x11->screen->white_pixel,
+		XCB_EVENT_MASK_EXPOSURE |
+		XCB_EVENT_MASK_KEY_PRESS | XCB_EVENT_MASK_KEY_RELEASE |
+		XCB_EVENT_MASK_BUTTON_PRESS | XCB_EVENT_MASK_BUTTON_RELEASE |
+		XCB_EVENT_MASK_POINTER_MOTION |
+		XCB_EVENT_MASK_STRUCTURE_NOTIFY
+	};
+	output->win = xcb_generate_id(x11->xcb_conn);
+	xcb_create_window(x11->xcb_conn, XCB_COPY_FROM_PARENT, output->win,
+		x11->screen->root, 0, 0, 1024, 768, 1, XCB_WINDOW_CLASS_INPUT_OUTPUT,
+		x11->screen->root_visual, mask, values);
+
+	output->surf = wlr_egl_create_surface(&x11->egl, &output->win);
+	if (!output->surf) {
+		wlr_log(L_ERROR, "Failed to create EGL surface");
+		free(output);
+		return NULL;
+	}
+
+	xcb_change_property(x11->xcb_conn, XCB_PROP_MODE_REPLACE, output->win,
+		x11->atoms.wm_protocols, XCB_ATOM_ATOM, 32, 1,
+		&x11->atoms.wm_delete_window);
+
+	char title[32];
+	if (snprintf(title, sizeof(title), "wlroots - %s", wlr_output->name)) {
+		xcb_change_property(x11->xcb_conn, XCB_PROP_MODE_REPLACE, output->win,
+			x11->atoms.net_wm_name, x11->atoms.utf8_string, 8,
+			strlen(title), title);
+	}
+
+	xcb_map_window(x11->xcb_conn, output->win);
+	xcb_flush(x11->xcb_conn);
+
+	struct wl_event_loop *ev = wl_display_get_event_loop(x11->wl_display);
+	output->frame_timer = wl_event_loop_add_timer(ev, signal_frame, output);
+
+	wl_event_source_timer_update(output->frame_timer, output->frame_delay);
+	wlr_output_update_enabled(wlr_output, true);
+
+	wl_list_insert(&x11->outputs, &output->link);
+	wlr_signal_emit_safe(&x11->backend.events.new_output, wlr_output);
+
+	return wlr_output;
+}
+
+void x11_output_handle_configure_notify(struct wlr_x11_output *output,
+		xcb_configure_notify_event_t *ev) {
+	struct wlr_x11_backend *x11 = output->x11;
+
+	wlr_output_update_custom_mode(&output->wlr_output, ev->width,
+		ev->height, output->wlr_output.refresh);
+
+	// Move the pointer to its new location
+	xcb_query_pointer_cookie_t cookie =
+		xcb_query_pointer(x11->xcb_conn, output->win);
+	xcb_query_pointer_reply_t *pointer =
+		xcb_query_pointer_reply(x11->xcb_conn, cookie, NULL);
+	if (!pointer) {
+		return;
+	}
+
+	struct wlr_event_pointer_motion_absolute abs = {
+		.device = &x11->pointer_dev,
+		.time_msec = x11->time,
+		.x = (double)pointer->root_x / output->wlr_output.width,
+		.y = (double)pointer->root_y / output->wlr_output.height,
+	};
+
+	wlr_signal_emit_safe(&x11->pointer.events.motion_absolute, &abs);
+	free(pointer);
+}
+
+bool wlr_output_is_x11(struct wlr_output *wlr_output) {
+	return wlr_output->impl == &output_impl;
+}