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Mad Dog McCree with Lightgun support



  • @MrLightgun i apologize for not knowing the terms. Can you please explain


  • Global Moderator

    @edmaul69

    Hey edmaul69. It's been a while. Hope all is well. The skeleton of it is that absolute input devices, such as USB light guns and touchscreens accept pointer coordinates wherever they're input, whereas relative input devices, like a traditional mouse, require that the input location be moved into place based on a starting and ending of movement. This gets cloudy with light gun reticles appearing to behave like relative input on screen, but the reticle is really just being drawn in absolute coordinates as they change.

    On a touchscreen, emulated software needing relative input often requires the input cursor to be drug into location and sometimes just fails to function outright. If I'm remembering correctly, RetroArch does something interesting in converting absolute to relative on-the-fly and updates movement accordingly as it happens. If you've tried your guns with DOSBox and it's working well, there almost has to be some sort of base-level support for absolute devices, even if the info is being translated in some way. Maybe there's a setting that governs all this?



  • Hi @edmaul69

    It is a suprisingly awkward thing to explain though mediamogul has done a good attempt.

    Basically when you point your lightgun at the screen is the mouse cursor always in the same identical spot. In other words is it absolute? Or are you actually just moving the cursor around like a mouse with small movements and there is no consistency with the pointer location? If you turned of the crosshair can you play the game or would you completely lose track of where you were pointing?

    My understanding is that you are just moving the cursor around in small relative movements like a mouse. What I added to lr-dosbox is that the mouse cursor consistently lines up with where you are pointing, therefore you can play without a crosshair and aim as demonstrated in the video. This gives a Lightgun gaming experience as opposed to a mouse or wii remote style experience.

    I hope that makes sense.



  • @MrLightgun any chance you can share the lr-dosbox you created?


  • Global Moderator

    @MrLightgun said in Mad Dog McCree with Lightgun support:

    What I added to lr-dosbox is that the mouse cursor consistently lines up with where you are pointing, therefore you can play without a crosshair and aim as demonstrated in the video. This gives a Lightgun gaming experience as opposed to a mouse or wii remote style experience.

    I imagine this has to be somewhat serendipitous to your personal play environment, as even absolute coordinates are subjective to the location of the input device where USB light guns are concerned. All the guns I've used personally, as well as the Wiimote/Dolphin Bar combo make use of absolute coordinates. However, based on the technology, their accuracy is dependent on a calibration routine of some kind, either with its own external software, such as the AimTrak options, or within certain games themselves.

    Since calibration can be undesirable, or even impossible in certain situations, the go-to solution is usually to add the cross-hairs so often seen. For example, Wii games make use of on-screen crosshairs almost exclusively, in what is most like an attempt to streamline the gaming experience. However, there's a few games in the library that allow calibration, as well as the option to turn the crosshairs off. Played this way, the games feel and behave very close to the original skill-based experience we all remember.

    What would be great is if RetroArch were to implement a uniform calibration option for absolute USB light gun devices. The method to achieve this is already outlined in the AimTrak confonf utility and is fairly straight-forward as far as I can tell. I believe it's really just adjusting the mouse coordinates based on the offset observed from the setup utility. I always meant to look at it more closely, but have yet to find the time.



  • @edmaul69 said in Mad Dog McCree with Lightgun support:

    @MrLightgun any chance you can share the lr-dosbox you created?

    Hi @edmaul69, it only works with my Sinden Lightgun so I need to complete the bits to make it use the standard Lightgun API. I've promised on various threads I'm going to complete this and merge/publish by sometime in June, but hopefully sooner. I'm very busy with my Kickstarter till mid May. I hope that won't be too painful a wait.



  • @mediamogul said in Mad Dog McCree with Lightgun support:

    @MrLightgun said in Mad Dog McCree with Lightgun support:

    What I added to lr-dosbox is that the mouse cursor consistently lines up with where you are pointing, therefore you can play without a crosshair and aim as demonstrated in the video. This gives a Lightgun gaming experience as opposed to a mouse or wii remote style experience.

    I imagine this has to be somewhat serendipitous to your personal play environment, as even absolute coordinates are subjective to the location of the input device where USB light guns are concerned. All the guns I've used personally, as well as the Wiimote/Dolphin Bar combo make use of absolute coordinates. However, based on the technology, their accuracy is dependent on a calibration routine of some kind, either with its own external software, such as the AimTrak options, or within certain games themselves.

    Since calibration can be undesirable, or even impossible in certain situations, the go-to solution is usually to add the cross-hairs so often seen. For example, Wii games make use of on-screen crosshairs almost exclusively, in what is most like an attempt to streamline the gaming experience. However, there's a few games in the library that allow calibration, as well as the option to turn the crosshairs off. Played this way, the games feel and behave very close to the original skill-based experience we all remember.

    What would be great is if RetroArch were to implement a uniform calibration option for absolute USB light gun devices. The method to achieve this is already outlined in the AimTrak confonf utility and is fairly straight-forward as far as I can tell. I believe it's really just adjusting the mouse coordinates based on the offset observed from the setup utility. I always meant to look at it more closely, but have yet to find the time.

    Hi @mediamogul , absolute coordinates are correctly absolute though as a standard in most implementations in RetroPie, its that's the Lightgun technology is not accurate without repeated calibration which is pretty much the whole point of the Sinden Lightgun, to solve this problem :-)


  • Global Moderator

    @MrLightgun said in Mad Dog McCree with Lightgun support:

    which is pretty much the whole point of the Sinden Lightgun, to solve this problem

    Well, paint me purple and call me the Grimace... I want one. I'll have to look into the Kickstarter later tonight.

    Also, I was just joking about the purple thing. There are no expectations that you actually make good on that request.



  • @mediamogul

    Also, I was just joking about the purple thing. There are no expectations that you actually make good on that request.

    alt text


  • Global Moderator

    @backstander

    Never has purple been so perfectly personified.



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