The check `Distance > 0.0f` is redundant because the same check already exists in the outer if-statement and the variable `Distance` is never modified.
The check `D >= 0.0f` is redundant because mathematically any distance is greater or equal to zero.
Reduce the memory footprint of the tool by unloading the map data as soon as possible instead of only implicitly when the `CDataFileReader` is destructed.
Use `log_info` and `log_error` instead of `dbg_msg`.
Add error messages when output files cannot be opened for writing.
Move log messages regarding files being written so they are only printed when the files are actually being written.
Opening links and files with the `open_link` and `open_file` functions does not work on Android, as the `open_link` function uses `fork` which is not supported on Android. This also seems to cause a strange bug where client networking partially breaks. Currently, after trying to open any link, connecting to servers is not possible anymore but the server browser still works, with the connection getting stuck randomly in the connecting/loading state.
SDL implements URL opening, including of file URIs, with the `SDL_OpenURL` function for most systems including Android. However, using `SDL_OpenURL` for all systems has several downsides:
1. The `SDL_OpenURL` function is only available since SDL 2.0.14, in particular not for the Ubuntu 20 CI runner. Hence, we would either have to conditionally compile the link opening function to a null-implementation or fallback to using the existing `open_link` function.
2. We would be undoing some additional fixes in the `open_link` function for Windows, which are not included in the Windows implementation of `SDL_OpenURL`.
3. This would also replace the use of `open` on UNIX with `xdg-open`.
4. This would move the functionality to open links and files from the base to the engine client, so we could not have tools or the server potentially making use of this functionality in the future (e.g. open a folder for convenience).
Implementing link and file opening for Android ourselves is too much effort and potentially made even harder by SDL already managing all the unique JVM resources in the `SDLActivity`.
Therefore, the `SDL_OpenURL` function is only used for Android, which is always based on the latest SDL2 version. The original `open_link` functionality is kept for the other systems. For this purpose, the `IClient::ViewLink` and `ViewFile` functions are added to wrap `open_link` and `open_file` for the client and also reduce some duplicate code for error logging.
Unfortunately, testing also revealed that `SDL_OpenURL` does not currently support opening file URIs, at least not of files the internal storage location, which all the DDNet client's files would be located in. At least opening URLs works and neither breaks networking anymore.