Replace non-leading tabs with spaces, using:

find -type f |  # list all regular files
  grep -E '\.(h|cpp|mm)$' |  # filter for source files
  grep -v '/mt_' |  # filter out generated files
  grep -v '/vendor/' | # and vendored GL
  xargs -n 1 -P $(nproc) ./replace_non_leading_tabs.lua  # reformat everything

source/Irrlicht/CGLXManager.h

@@ -68,7 +68,7 @@ private:
 	SExposedVideoData CurrentContext;
 	XVisualInfo *VisualInfo;
 	void *glxFBConfig; // GLXFBConfig
-	XID GlxWin;		   // GLXWindow
+	XID GlxWin;        // GLXWindow
 };
 }
 }