Add support to EGL to on the fly destroy the resulting surface

Source/Core/Common/GL/GLInterface/EGL.cpp

@@ -11,7 +11,8 @@
 // Show the current FPS
 void cInterfaceEGL::Swap()
 {
-	eglSwapBuffers(egl_dpy, egl_surf);
+	if (egl_surf != EGL_NO_SURFACE)
+		eglSwapBuffers(egl_dpy, egl_surf);
 }
 void cInterfaceEGL::SwapInterval(int Interval)
 {
@@ -98,10 +99,11 @@ void cInterfaceEGL::DetectMode()
 // Call browser: Core.cpp:EmuThread() > main.cpp:Video_Initialize()
 bool cInterfaceEGL::Create(void *window_handle, bool core)
 {
-	const char *s;
 	EGLint egl_major, egl_minor;
 
 	egl_dpy = OpenDisplay();
+	m_host_window = (EGLNativeWindowType) window_handle;
+	m_has_handle = !!window_handle;
 
 	if (!egl_dpy)
 	{
@@ -116,7 +118,6 @@ bool cInterfaceEGL::Create(void *window_handle, bool core)
 	}
 
 	/* Detection code */
-	EGLConfig config;
 	EGLint num_configs;
 
 	DetectMode();
@@ -154,7 +155,7 @@ bool cInterfaceEGL::Create(void *window_handle, bool core)
 		break;
 	}
 
-	if (!eglChooseConfig( egl_dpy, attribs, &config, 1, &num_configs))
+	if (!eglChooseConfig( egl_dpy, attribs, &m_config, 1, &num_configs))
 	{
 		INFO_LOG(VIDEO, "Error: couldn't get an EGL visual config\n");
 		exit(1);
@@ -165,43 +166,86 @@ bool cInterfaceEGL::Create(void *window_handle, bool core)
 	else
 		eglBindAPI(EGL_OPENGL_ES_API);
 
-	EGLNativeWindowType host_window = (EGLNativeWindowType) window_handle;
-	EGLNativeWindowType native_window = InitializePlatform(host_window, config);
-
-	s = eglQueryString(egl_dpy, EGL_VERSION);
-	INFO_LOG(VIDEO, "EGL_VERSION = %s\n", s);
-
-	s = eglQueryString(egl_dpy, EGL_VENDOR);
-	INFO_LOG(VIDEO, "EGL_VENDOR = %s\n", s);
-
-	s = eglQueryString(egl_dpy, EGL_EXTENSIONS);
-	INFO_LOG(VIDEO, "EGL_EXTENSIONS = %s\n", s);
-
-	s = eglQueryString(egl_dpy, EGL_CLIENT_APIS);
-	INFO_LOG(VIDEO, "EGL_CLIENT_APIS = %s\n", s);
-
-	egl_ctx = eglCreateContext(egl_dpy, config, EGL_NO_CONTEXT, ctx_attribs );
+	egl_ctx = eglCreateContext(egl_dpy, m_config, EGL_NO_CONTEXT, ctx_attribs );
 	if (!egl_ctx)
 	{
 		INFO_LOG(VIDEO, "Error: eglCreateContext failed\n");
 		exit(1);
 	}
 
-	egl_surf = eglCreateWindowSurface(egl_dpy, config, native_window, nullptr);
-	if (!egl_surf)
+	std::string tmp;
+	std::istringstream buffer(eglQueryString(egl_dpy, EGL_EXTENSIONS));
+	while (buffer >> tmp)
 	{
-		INFO_LOG(VIDEO, "Error: eglCreateWindowSurface failed\n");
-		exit(1);
+		if (tmp == "EGL_KHR_surfaceless_context")
+		{
+			m_supports_surfaceless = true;
+			break;
+		}
 	}
 
+
+	CreateWindowSurface();
 	return true;
 }
 
+void cInterfaceEGL::CreateWindowSurface()
+{
+	if (m_has_handle)
+	{
+		EGLNativeWindowType native_window = InitializePlatform(m_host_window, m_config);
+		egl_surf = eglCreateWindowSurface(egl_dpy, m_config, native_window, nullptr);
+		if (!egl_surf)
+		{
+			INFO_LOG(VIDEO, "Error: eglCreateWindowSurface failed\n");
+			exit(1);
+		}
+	}
+	else if (!m_supports_surfaceless)
+	{
+		EGLint attrib_list[] =
+		{
+			EGL_NONE,
+		};
+		egl_surf = eglCreatePbufferSurface(egl_dpy, m_config, attrib_list);
+		if (!egl_surf)
+		{
+			INFO_LOG(VIDEO, "Error: eglCreatePbufferSurface failed");
+			exit(2);
+		}
+	}
+	else
+	{
+		egl_surf = EGL_NO_SURFACE;
+	}
+}
+
+void cInterfaceEGL::DestroyWindowSurface()
+{
+	if (egl_surf != EGL_NO_SURFACE && !eglDestroySurface(egl_dpy, egl_surf))
+		NOTICE_LOG(VIDEO, "Could not destroy window surface.");
+	egl_surf = EGL_NO_SURFACE;
+}
+
 bool cInterfaceEGL::MakeCurrent()
 {
 	return eglMakeCurrent(egl_dpy, egl_surf, egl_surf, egl_ctx);
 }
 
+void cInterfaceEGL::UpdateHandle(void* window_handle)
+{
+	m_host_window = (EGLNativeWindowType)window_handle;
+	m_has_handle = !!window_handle;
+}
+
+void cInterfaceEGL::UpdateSurface()
+{
+	ClearCurrent();
+	DestroyWindowSurface();
+	CreateWindowSurface();
+	MakeCurrent();
+}
+
 bool cInterfaceEGL::ClearCurrent()
 {
 	return eglMakeCurrent(egl_dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
@@ -218,8 +262,7 @@ void cInterfaceEGL::Shutdown()
 		eglMakeCurrent(egl_dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
 		if (!eglDestroyContext(egl_dpy, egl_ctx))
 			NOTICE_LOG(VIDEO, "Could not destroy drawing context.");
-		if (!eglDestroySurface(egl_dpy, egl_surf))
-			NOTICE_LOG(VIDEO, "Could not destroy window surface.");
+		DestroyWindowSurface();
 		if (!eglTerminate(egl_dpy))
 			NOTICE_LOG(VIDEO, "Could not destroy display connection.");
 		egl_ctx = nullptr;

Source/Core/Common/GL/GLInterface/EGL.h

@@ -11,6 +11,15 @@
 
 class cInterfaceEGL : public cInterfaceBase
 {
+private:
+	EGLConfig m_config;
+	bool m_has_handle;
+	EGLNativeWindowType m_host_window;
+	bool m_supports_surfaceless = false;
+
+	void CreateWindowSurface();
+	void DestroyWindowSurface();
+
 protected:
 	void DetectMode();
 	EGLSurface egl_surf;
@@ -20,6 +29,7 @@ protected:
 	virtual EGLDisplay OpenDisplay() = 0;
 	virtual EGLNativeWindowType InitializePlatform(EGLNativeWindowType host_window, EGLConfig config) = 0;
 	virtual void ShutdownPlatform() = 0;
+
 public:
 	void Swap() override;
 	void SwapInterval(int interval) override;
@@ -29,4 +39,6 @@ public:
 	bool MakeCurrent() override;
 	bool ClearCurrent() override;
 	void Shutdown() override;
+	void UpdateHandle(void* window_handle) override;
+	void UpdateSurface() override;
 };

Source/Core/Common/GL/GLInterfaceBase.h

@@ -42,6 +42,8 @@ public:
 	virtual void SetBackBufferDimensions(u32 W, u32 H) {s_backbuffer_width = W; s_backbuffer_height = H; }
 	virtual void Update() { }
 	virtual bool PeekMessages() { return false; }
+	virtual void UpdateHandle(void* window_handle) {}
+	virtual void UpdateSurface() {}
 };
 
 extern std::unique_ptr<cInterfaceBase> GLInterface;