Revert "Use EGL over GLX" (#15315)

This reverts commit aa273119f2.

irr/src/CGLXManager.h

@@ -0,0 +1,76 @@
+// Copyright (C) 2013 Christian Stehno
+// This file is part of the "Irrlicht Engine".
+// For conditions of distribution and use, see copyright notice in Irrlicht.h
+
+#pragma once
+
+#ifdef _IRR_COMPILE_WITH_GLX_MANAGER_
+
+#include "SIrrCreationParameters.h"
+#include "SExposedVideoData.h"
+#include "IContextManager.h"
+#include "SColor.h"
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+// we can't include glx.h here, because gl.h has incompatible types with ogl es headers and it
+// cause redefinition errors, thats why we use ugly trick with void* types and casts.
+
+namespace irr
+{
+namespace video
+{
+// GLX manager.
+class CGLXManager : public IContextManager
+{
+public:
+	//! Constructor.
+	CGLXManager(const SIrrlichtCreationParameters &params, const SExposedVideoData &videodata, int screennr);
+
+	//! Destructor
+	~CGLXManager();
+
+	// Initialize
+	bool initialize(const SIrrlichtCreationParameters &params, const SExposedVideoData &data) override;
+
+	// Terminate
+	void terminate() override;
+
+	// Create surface.
+	bool generateSurface() override;
+
+	// Destroy surface.
+	void destroySurface() override;
+
+	// Create context.
+	bool generateContext() override;
+
+	// Destroy context.
+	void destroyContext() override;
+
+	//! Get current context
+	const SExposedVideoData &getContext() const override;
+
+	//! Change render context, disable old and activate new defined by videoData
+	bool activateContext(const SExposedVideoData &videoData, bool restorePrimaryOnZero) override;
+
+	// Get procedure address.
+	void *getProcAddress(const std::string &procName) override;
+
+	// Swap buffers.
+	bool swapBuffers() override;
+
+	XVisualInfo *getVisual() const { return VisualInfo; } // return XVisualInfo
+
+private:
+	SIrrlichtCreationParameters Params;
+	SExposedVideoData PrimaryContext;
+	SExposedVideoData CurrentContext;
+	XVisualInfo *VisualInfo;
+	void *glxFBConfig; // GLXFBConfig
+	XID GlxWin;        // GLXWindow
+};
+}
+}
+
+#endif