From 4fb515a86d744e11f33ef058512a2d98ea8bc917 Mon Sep 17 00:00:00 2001
From: TellowKrinkle <tellowkrinkle@gmail.com>
Date: Sun, 25 Jun 2023 22:37:15 -0500
Subject: [PATCH] VideoBackends:OGL: Wayland support

---
 Source/Core/Common/CMakeLists.txt             |  7 +++
 Source/Core/Common/GL/GLContext.cpp           | 10 ++++
 .../Core/Common/GL/GLInterface/EGLWayland.cpp | 47 +++++++++++++++++++
 .../Core/Common/GL/GLInterface/EGLWayland.h   | 28 +++++++++++
 4 files changed, 92 insertions(+)
 create mode 100644 Source/Core/Common/GL/GLInterface/EGLWayland.cpp
 create mode 100644 Source/Core/Common/GL/GLInterface/EGLWayland.h

diff --git a/Source/Core/Common/CMakeLists.txt b/Source/Core/Common/CMakeLists.txt
index 894fd38128..49d8402b1d 100644
--- a/Source/Core/Common/CMakeLists.txt
+++ b/Source/Core/Common/CMakeLists.txt
@@ -308,6 +308,13 @@ if(ENABLE_EGL AND EGL_FOUND)
   target_link_libraries(common PUBLIC ${EGL_LIBRARIES})
 endif()
 
+if(ENABLE_WAYLAND)
+  target_sources(common PRIVATE
+    GL/GLInterface/EGLWayland.cpp
+    GL/GLInterface/EGLWayland.h
+  )
+endif()
+
 if(WIN32)
   target_sources(common PRIVATE
     CompatPatches.cpp
diff --git a/Source/Core/Common/GL/GLContext.cpp b/Source/Core/Common/GL/GLContext.cpp
index d2b0ae0076..67372c4f73 100644
--- a/Source/Core/Common/GL/GLContext.cpp
+++ b/Source/Core/Common/GL/GLContext.cpp
@@ -19,6 +19,9 @@
 #if HAVE_X11
 #include "Common/GL/GLInterface/EGLX11.h"
 #endif
+#if HAVE_WAYLAND
+#include "Common/GL/GLInterface/EGLWayland.h"
+#endif
 #if defined(ANDROID)
 #include "Common/GL/GLInterface/EGLAndroid.h"
 #endif
@@ -103,6 +106,13 @@ std::unique_ptr<GLContext> GLContext::Create(const WindowSystemInfo& wsi, bool s
   if (wsi.type == WindowSystemType::X11)
     context = std::make_unique<GLContextEGLX11>();
 #endif
+  
+#endif
+#if HAVE_WAYLAND && HAVE_EGL
+  if (wsi.type == WindowSystemType::Wayland)
+    context = std::make_unique<GLContextEGLWayland>();
+#endif
+#if HAVE_EGL
   if (wsi.type == WindowSystemType::Headless || wsi.type == WindowSystemType::FBDev)
     context = std::make_unique<GLContextEGL>();
 #endif
diff --git a/Source/Core/Common/GL/GLInterface/EGLWayland.cpp b/Source/Core/Common/GL/GLInterface/EGLWayland.cpp
new file mode 100644
index 0000000000..1571f2de6f
--- /dev/null
+++ b/Source/Core/Common/GL/GLInterface/EGLWayland.cpp
@@ -0,0 +1,47 @@
+// Copyright 2023 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "Common/GL/GLInterface/EGLWayland.h"
+#include "Common/MsgHandler.h"
+
+GLContextEGLWayland::~GLContextEGLWayland()
+{
+  if (m_window)
+    m_wl_egl_window_destroy(m_window);
+}
+
+void GLContextEGLWayland::Update(u32 width, u32 height)
+{
+  GLContext::Update(width, height);
+  if (m_window)
+    m_wl_egl_window_resize(m_window, width, height, 0, 0);
+}
+
+EGLDisplay GLContextEGLWayland::OpenEGLDisplay()
+{
+  return eglGetDisplay(static_cast<EGLNativeDisplayType>(m_wsi.display_connection));
+}
+
+EGLNativeWindowType GLContextEGLWayland::GetEGLNativeWindow(EGLConfig config)
+{
+  if (!m_wayland_lib.IsOpen())
+  {
+    std::string name = Common::DynamicLibrary::GetVersionedFilename("wayland-egl", 1);
+    m_wayland_lib.Open(name.c_str());
+    if (!m_wayland_lib.IsOpen())
+    {
+      PanicAlertFmt("Failed to load {}", name);
+      return reinterpret_cast<EGLNativeWindowType>(m_window);
+    }
+#define LOAD(x) m_wayland_lib.GetSymbol(#x, &m_##x)
+    LOAD(wl_egl_window_create);
+    LOAD(wl_egl_window_destroy);
+    LOAD(wl_egl_window_resize);
+#undef LOAD
+  }
+  if (m_window)
+    m_wl_egl_window_destroy(m_window);
+  m_window = m_wl_egl_window_create(static_cast<wl_surface*>(m_wsi.render_surface),
+                                    m_wsi.render_surface_width, m_wsi.render_surface_height);
+  return reinterpret_cast<EGLNativeWindowType>(m_window);
+}
diff --git a/Source/Core/Common/GL/GLInterface/EGLWayland.h b/Source/Core/Common/GL/GLInterface/EGLWayland.h
new file mode 100644
index 0000000000..73cc90064b
--- /dev/null
+++ b/Source/Core/Common/GL/GLInterface/EGLWayland.h
@@ -0,0 +1,28 @@
+// Copyright 2023 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <wayland-client-protocol.h>
+#include "Common/DynamicLibrary.h"
+#include "Common/GL/GLInterface/EGL.h"
+
+struct wl_egl_window;
+struct wl_surface;
+
+class GLContextEGLWayland final : public GLContextEGL
+{
+public:
+  ~GLContextEGLWayland() override;
+
+  void Update(u32 width, u32 height) override;
+
+protected:
+  EGLDisplay OpenEGLDisplay() override;
+  EGLNativeWindowType GetEGLNativeWindow(EGLConfig config) override;
+  Common::DynamicLibrary m_wayland_lib;
+  wl_egl_window* (*m_wl_egl_window_create)(wl_surface* surface, int width, int height);
+  void (*m_wl_egl_window_destroy)(wl_egl_window* window);
+  void (*m_wl_egl_window_resize)(wl_egl_window* window, int width, int height, int dx, int dy);
+  wl_egl_window* m_window = nullptr;
+};