Edit 3 (2021-08-08): We have released a third hotfix build; we finally fixed the annoying RageFile glitch that was causing the hash system to be different from StepMania 5.1/5.0.12. Sorry about all this hassle, we fixed a wedge of bugs in the loading system, but did not expect everyone to have built massive amounts of stuff on top of these bugs being there, so we have adjusted the system so backward compatible themes/API/ScoreShare/Groovestats/etc. work again once more. A build is also avaliable for Intel-based Macintosh again; we had run into difficulties preventing an Intel-compatible build of the previous hotfix build.

Edit 3 (2021-08-06): We have released one more hotfix build, HF2. It includes a few things we were going to leave to the next release, but as we had to fix bugs in them anyway, it was easier to just add them now.

Alpha 4.9.9HF

We had pulled Alpha 4.9.9 shortly after release in order to fix some late-breaking bugs. But now that those are all taken care of, we have released Alpha 4.9.9HF!

There are some additional highlights in this build on top of what is already in Alpha 4.9.9, including:

  • We have fixed the signed macOS builds. In order to fulfill security requirements in newer macOS versions on Intel-based devices, we also performed some fixes to gh mode; way the notes were cast have been fixed, fever/star power has been sorted to be more GH3-like, and taps and open strums are also tweaked to be better. Please give them a try and let us know! A theme for this mode is in the works, so apologies for the barebone approach we have at the moment. It's also why we are an alpha after all...
  • There were several issues with the notes loaders and how antivirus/security software apps were seeing OutFox when we were loading simfiles. We have addressed this by allowing you all to add more than one simfile (i.e. .SSC, etc.) in a song folder, cutting down on the folder rabbit hole. As we move to a more multi-game engine, this will also allow you to keep things tidy on your drive, and ensure it is a seamless experience for you all. Of course, please check the audio files are the same for the chart you are going to add to the folder, as you may find you have a nasty sync issue, but we also now support multidifficulty setups, as this is required for pump and taiko specifically.
  • This hotfix also sees a tweak to the difficulty system used in OutFox. In the past it was tied to the DDR paradigm and then left to rot as one of those "StepMania Things". This however really stifled what we could do within the engine, especially with modes with different names/brackets etc. With the release of gddm and taiko we needed more difficulties than the game offered, so this has now been resolved. Themes which are based off of 5.1/5.0.x will still work due to the numbers being the same as before. If there are any issues with your theme, do let us know, but we have tested several with no issues.
  • We now support the #VOLUME and #PAN parameters for keysounds in BMS-derived formats.
  • We have fixed a 17 year-old bug where the engine would attempt to run commands on tweens that don't exist during transitions.

The original post follows:

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Project OutFox Alpha 4.9.9 has been released! Given how long it's been since our last alpha release, there's a lot to go over with this version. This is a summary of most of the major changes; you can read the complete changelog on on OutFox.wiki,


Game types


Project OutFox has begun to position itself as a multi-game engine, designed to be more of a working museum dedicated to preserving the history of rhythm gaming. We have been building upon and fixing game types that were inherited from the StepMania codebase, as well as implementing new game types that have never been implemented in StepMania before. Carrying on from 4.9.8, there have been various bug fixes and enhancements to some of our non-dance modes, as well as one brand new mode:

  • beat: There are bug fixes for the BMS loader array and missing difficulties.
  • dance: We have preliminary support for a new hold type known as a minefield (also colliqually known as a "mine hold"). They are a hold that is a mine, penalizing you each time you press the corresponding input.
  • ez2: A new default noteskin has been added.


  • gddm:

    • We have added a parser for loading DTX files; we have planned to 'straddle' support for the DTXMania NX/Ver. K layouts for the specified channels from the documentation, as these appear to be the most popular branches of this. It will be improved in time, as we get better knowledge of this system. For more information on supported DTX/BMS/PMS channels, see the related section on the official changelog.
    • We also support the combined" lane system which adds lane 2 and lane 3’s extra notes, and Real mode (again, REAL filenames are yet to be parsed as such, the engine makes a ‘guess’ on this!)
    • gddm still needs a lot of work and optimisation before we will consider it ‘ready’, so do expect the odd quirk or weird behaviour, and let us know what you think/would like to see as we define the mode and its featureset and support.We will be working on the gdgf parser in the coming months so that the guitar/bass charts will work as well.
    • We do not support XA file decoding at this time, we are looking into options. If you have a DTX file with XA files contained, they will just be played as silence, but won’t crash the game.
    • The game does not currently support the #PAN and #VOLUME configurations as of this alpha, so some keysounds will be louder than expected. Apologies for this in advance; we wanted to get a release out as it’s been so long, so this is still being worked on.
      • #PAN and #VOLUME are now supported on 4.9.9HF! They are completely supported in gddm from the parser, (do reset your cache of course!) and they also work in beat/popn. taiko will need the support as well, so shout out to Jous for putting up with my waaaahh-luigi on getting it added to the game. This build also supports the hidden chips/keysounds for gddm and we'll work on getting the final compatibility added in due course.
  • gdgf: Community member yaladre has contributed a new DTX noteskin with a more familiar appearance.

  • gh: A note positioning bug has been fixed, while the gameplay screen in Soundwaves has been tidyed.


  • para: We have added a new eight-sensor style, adding back-left, back, and back-right directions. This mode was originally designed for the arcade cabinet for when the player twirls or turns, but was never actually implemented. The sensors for the back are actually there! For those who feel adventurous, we will be publishing some information on how to make your own 360-degree 8 sensor controller in due course.


  • popn:
    • This mode also had a few tweaks and adjustments mainly in how keysounds are loaded within the game, which should make it smoother overall.
    • A bug was fixed that prevented some seven-button charts from being parsed correctly.
    • In addition, we have also added two-player (versus) and 18-button (double) modes! This was not available on the original client, but it did always irk us how there were never two-player options other than three-button battle. We plan to have battle mode, as well as a dedicated experience for this game type, in a future build. There is no PMS/PME support for this style yet.


  • pump:
    • We have fixed the scoring bug that was in the previous build; thank you for those who took the time to report the issues. Keep in mind that Soundwaves still uses dance paradigms for scoring, but other themes that use different scoring systems based on the official games should work correctly now.
    • The tickcount for combos on holds has been tweaked to work correctly, as there was a miscalculation in the offset math inherited from upstream. This now behaves as expected.
    • We have added support for co-op charts; the included co-op noteskin currently supports up to five different players, but charts can support up to ten.
      • The player numbers on the noteskins are separately labeled, so with a few adjustments and extra assets, you will be able to update any noteskin to work with co-op. Co-op charts made on StepF2/StepP1 should work on OutFox,
      • Co-op charts made on StepF2/StepP1 should work on OutFox, however, better note types are currently being developed by Jousway so that there can be more than four real players defined. Stay tuned!
      • We're still working on improving SF2/SP1 custom charts parsing. Except for a few charts, you can play the majority of content made for it on OutFox with no problems. As always, if you find any oddities make sure you report them to us!
      • Those of you who have reported that we still have a ‘superb’ bug on holds, this will be fixed when we introduce the new piu mode . Remember that the pump mode is getting quality of life updates for now, before we move over to updating things properly in the future.
      • Micro/mini-holds also do not trigger misses/cause a weird tick to happen anymore, and there also are no ‘phantom’ mines in long (5+ measure) holds - this was an oddity which has been fixed now.

Last but not least, we have added a brand-new game type as well, taiko (also referred to in the context of OutFox as "TaiTai"). It simulates a popular rhythm game where you hit a drum in its face.


As with gh on the previous alpha, this is a "preliminary" implementation. Some of the quirkier parts of this mode are a work in progress; bear with us as we also write new parsers for this mode, and develop a dedicated theme/interface for it. We plan to add support for the special note types and other effects in the game, as well as improve timing and other bits and pieces that are still yet to do. We still have the scoring and timing system to finish, along with effects on double notes/taps and the "roll" notes which you hit as much as you can. The autogen for this mode has been rewritten by Jousway to generate charts more approriate for the game from existing charts in other modes, so that you don't get odd holds/overlaps in things.

Feel free to give it a try and let us know what you think!

All game types have access to features such as the built-in chart editor and modifier systems, allowing you to extend your content to as many as 56 styles in 15 gametypes as of this release.

Technical changes

MIDI input

Due to the interest we had been getting from the past two alpha releases in the form of gddm and techno, several players that were not on Windows did inquire about the possibility of there being a new MIDI driver available for Mac and Linux users, So we decided as a team to move forward and produce one. This enables you to play Project OutFox with MIDI instruments and controllerd, such as electronic drums, keyboards, DJ mixers, and a prototype mini FSR pad we made using a Teensy LC and some tiny FSR sensors.


It uses the PortMidi library, and there is no need to have any extra applications "translating" it to keystrokes (unless you're doing MIDI via an iPhone something like that of course), but native MIDI controllers work a treat. If you have a midi device and want to try this out, you will need to load up your preferences.ini in your save folder, locate the inputdrivers= part, and then make sure it looks like this inputdrivers=portmidi,SDL

This driver works on Windows, Linux, ARM (rPi and Rockchip aarch64 SoCs), and macOS. To enable the driver, use the line InputDrivers=SDL,portmidi in Preferences.ini. We have currently coded it for a single device at a time, but do let us know if you feel there is a need for multiple device support, or if you find a device that doesn'’'t behave.


We have added a preference, TurnOffWMCompositor, to disable compositing effects in window managers when Project OutFox is running.

We have also fixed a renderer bug that was causing edge case crashes under KDE Plasma Desktop, and added a stub for an upcoming Pipewire audio driver.


On macOS, our builds are now signed and notarized. You no longer have to fiddle with Gatekeeper/quarantine/etc. to run Project OutFox on your Mac. You can now just download and install it as you would other applications.

We also fixed an edge case lag spike on M1 Macbook Air models when using a Bluetooth audio device or controller.


There has also been work done on a small side part of the game, while we have been waiting for a fix from upstream in regards to the "polling/framerate" "issue that a lot of folks have helping us diagnose for some time. The long and the short of the issue, it meant on some songs, the input would skew towards the update loop rather than honouring its timestamp, thus producing spikes on the scoring graph on the results screen, and make a odd looking ‘stair’ display on the scatterplot of the steps and judgements taken.

To resolve this while we’re waiting a fix, we have reimplemented the old legacy driver that was on 5.2/5.1 and adapted it for OutFox. This driver can be tempremental, but it seemed to behave with the devices we tested it with. If you tend to find that your input is affected with the message loop issue, you can set up the driver with the following instructions:

  • Open Preferences.ini in your Save folder
  • Locate the line InputDrivers
  • Change the line to InputDrivers=legacy,minisdl
  • If you wish to use the new portmidi driver as well you can use InputDrivers=legacy,minisdl,portmidi

This will allow you to run the game with minimal resources, keeping vsync on, and should remove any previous issues of FPS/rate/polling problems. When we have the fix from upstream, we’ll revisit and modernise this with the newer drivers and processes.

On the Test Input screen, you will see a new Window Handler ‘Aux’ driver. This is just the driver that manages the window controls, maximises, fullscreens, etc, so no need to worry about it. This will also show you that you have the correct drivers selected in the InputDrivers setting.

Rate and Pitch

Due to an overwhelming set of requests, we have taken time to fix and modernise the rate/haste system which had been broken for a bit since this project began.

Pitch seemed to be a lottery (though we had not seen it work) and all the rate mod used to do was seemingly speed up the song with no other effect or option being honoured.

We have fixed the way the off/speed/pitch/speed and pitch options work, so they actually work. This took quite a bit of time to fix the internal pipelines for these, but the end effect is definitely fun. Thanks to Squirrel, Jousway and Jose for bringing this one up the pipeline to get it done for this release! To ensure compatibility with legacy themes, the system ‘defaults’ to how it was in 5.0.12, with a 0.01x increase, and being on the main menu as folks requested. This is a long overdue Quality of Life update for this, so we’re really pleased that its done.

Thanks to the stamina players that popped in to request this, and to mattm for saying that most wanted a speed and pitch option, which we have called ‘both’ internally to signify this change.

Default theme

  • We reordered the Select Game menu to move prominent game types closer to the top, and lesser-known/niche games towards the bottom. Please give us feedback if you feel a mode needs more representation/love!
  • We have been shortening and toning down excessive transitions and animations to make the menus in the Soundwaves theme faster.
  • We added the rate and sound effect settings to the first screen of Player Options (in addition to its historic location on Song Options) to make them easier to find.
  • A contributor to Tiny-Foxes' Soundwaves Community branch has added the capability for Soundwaves color schemes to specify custom difficulty colors. Whilst integrating this feature, we have also added all *The gameplay screen in gh mode has been tidied up to put more of a focus on the notefield.

Release notes and download

You can see the full changelog for Alpha 4.9.9 on OutFox.wiki, which has details on the other improvements and bug fixes featured in this build.


Give all of the new features and modes a try and be sure to give us your feedback! If you encounter any bug in the game, please report them on our bug tracker or our Discord server. We won't be able to fix bugs that are not reported to us. If you feel adventerous, also consider requesting access to our nightly build testing programme, as we are seeking testers for builds containing major internal changes.

You can also visit r/OutFox on Reddit for support and discussion of Project OutFox, and stream Project OutFox on Twitch.

This release of Project OutFox is dedicated to the memory of SHIKI, a Japanese musician who was an influential figure in the worlds of doujin trance, BMS, and rhythm game music. Our release artwork for Alpha 4.9.9 pays homage to Reach's classic simfile for "AIR"—one of SHIKI's most well-known songs.