DS4MapperTest - Looking Back

What Was It?

DS4MapperTest was the last version of a test ground application for developing mapper ideas that would hopefully replace DS4Windows. Several input controllers were supported including DS4, DualSense, Switch Pro, JoyCon, and even the Steam Controller. Action Set and Action Layer support was available. Many output action types were available and preliminary activator support was available. Virtual KB+M event support (via FakerInput) and virtual Xbox 360 and DS4 output support (via ViGEmBus) was possible.

Back History

Testing with implementing a new controller mapper started because the mapper used in DS4Windows is a bit limiting and I figured it would be easier to write brand new mapper code and test some ideas rather than try to shoehorn something in the DS4Windows code. The experimental mapper went through a few different iterations over the span of about two years. The first iteration was started as a way to test connecting a Switch Pro controller to a Windows PC. All actions were coded directly and only basic direct mapping in backend code was possible. The handshake routine was added into DS4Windows a bit later on IIRC.

Later on, various actions were added to the code and a separate Steam Controller version of the mapper was made. My work on sc-controller helped with getting initial Steam Controller connections working outside of Steam; some of the work in the mapper made it back into sc-controller. Having some form of Action Set support is necessary to take full advantage of what the Steam Controller can offer so more of an effort was started to add functionality that Steam Input offers. Creating an Action Set system was not out of the question as I had made a system before. It took quite a bit of experimenting to make an Action Layer system that was quick to switch layers and functioned properly; even the Action Layer system in Steam Input can get stuck on the wrong layer sometimes. Allowing property cascading was a really tough feature to work out.

Eventually, I wanted to use the newly created Action Layer system with the DS4 controller. That led to writing another version of the experimental mapper.

Consolidation

Having to carry changes over between three different projects was becoming a big time sink. It was time to start merging projects together and ease my workload. Switch Pro support was carried over first as that backend code was closer to what was written for the DS4 version; JoyCon controller support was added later. It was not until about the end of the DS4MapperTest project that Steam Controller support was added into the code as the Steam Controller mapper had some custom quirks that were a bit hard to carry over.

Current Status

I stopped pushing changes for DS4MapperTest around the end of January 2024. I have made some small changes on my machine but not anything too great. The biggest change was adding haptic feedback for the Circular touchpad action; having haptic feedback when mouse wheel clicks happen really makes that type of action easier to control. One recent small change is that I realized that throttling the poll rate double remainder makes a big difference for smoothing out the mouse cursor without losing precision. If only I had thought of that idea when I was still working on DS4Windows. Stick mouse and Gyro mouse could have been improved even more.

Although the project was technically a failure, I still use it occasionally so it was not a complete waste of time.