Add helper scripts and wlroots integration

Signed-off-by: Slendi <slendi@socopon.com>

src/compositor.cpp

@@ -1,6 +1,13 @@
 #include "compositor.h"
 
 #include "common.h"
+#include <wayland-server.h>
+// wlroots is a C library; wrap headers in extern "C"
+extern "C" {
+#include <wlr/backend.h>
+#include <wlr/util/log.h>
+}
+#include "wlr/openxr_gl.h"
 
 #include <cstring>
 #include <iostream>
@@ -193,10 +200,40 @@ void Compositor::create_session()
 		ci.createFlags = 0;
 		OPENXR_CHECK(xrCreateSession, m_xr_instance, &ci, &m_session);
 	}
+	// --- wlroots integration: create Wayland display and OpenXR wlroots
+	// backend --- initialize wlroots logging
+	wlr_log_init(WLR_DEBUG, nullptr);
+	// create Wayland display
+	m_display = wl_display_create();
+	if (!m_display) {
+		throw std::runtime_error("Failed to create Wayland display");
+	}
+	// get event loop
+	m_event_loop = wl_display_get_event_loop(m_display);
+	if (!m_event_loop) {
+		wl_display_destroy(m_display);
+		throw std::runtime_error("Failed to get Wayland event loop");
+	}
+	// create the OpenXR wlroots backend
+	m_backend = wlr_openxr_backend_create(m_display, m_event_loop);
+	if (!m_backend || !wlr_backend_is_openxr(m_backend)) {
+		wl_display_destroy(m_display);
+		throw std::runtime_error("Failed to create OpenXR wlroots backend");
+	}
 }
 
 void Compositor::destroy_session()
 {
+	// destroy wlroots backend and Wayland display
+	if (m_backend) {
+		wlr_backend_destroy(m_backend);
+		m_backend = nullptr;
+	}
+	if (m_display) {
+		wl_display_destroy(m_display);
+		m_display = nullptr;
+	}
+	// destroy OpenXR session
 	OPENXR_CHECK(xrDestroySession, m_session);
 }
 
@@ -249,11 +286,17 @@ void Compositor::poll_events()
 
 void Compositor::run()
 {
+	// start the wlroots backend (this also begins XrSession)
+	if (!wlr_backend_start(m_backend)) {
+		throw std::runtime_error("Failed to start wlroots backend");
+	}
 	while (m_running) {
 		this->poll_events();
+		// dispatch Wayland events
+		wl_event_loop_dispatch(m_event_loop, 0);
 
 		if (m_session_running) {
-			// TODO: Render frame
+			// TODO: Render frame (per-eye rendering via OpenXR swapchain)
 		}
 	}
 }