According to the manual, it can be played with the Light Phaser or the Controller, but the controller should be in Port 2.
You can choose, in the Port 1/2 controls sub-menus, to which console port the controllers are mapped. If you map the 1st controller to Port 2 and vice-versa (2nd controller to Port 1), this will enable you to play using the controller, without a light gun device - the game will detect you have the controller in the 2nd port and start without light gun support.
@pinokiooo i'm not an expert (i did this once, long ago, with 2 mouses), but i remember dual pointer devices need udev as retroarch's input driver, and you might also need to set appropriate mouse indexes for each players in retroarch's input settings.
So I was able to make this work by simply unplugging the mouse from the pi, leaving the controller settings in retroarch for fceumm set to auto NOT zapper, and then under settings change zapper mode to mouse.
I've found that if you forget to unplug your mouse before you start the game you can simply unplug it and the wiimote will take over immediately as the mouse.
If using a wireless mouse you must unplug the dongle not just turn the power off to the mouse. This could be problematic for wireless keyboard/mouse combos as you have to unplug the dongle and lose both keyboard and ouse function.
So far I havent been able to get the hot keys to work in game (even thought they work fine in emulationstation) to exit the game and have to use the keyboard for that unless you have a gamepad installed (which doesnt interfere with the wiimote as a mouse as a zapper) then you can use the game pad to exit the game.
@g30ff the drive is just a script that boots a service, but yep tried that ... and also working with Sinden too .. but since this was such a needle, was hoping there was some known mouse issues lingering that could help me pinpoint a resultion
@trapexit I am having the same issue as @escc1986 where I am unable to reload in Mad Dog McCree. I am also having similar issues with Space Pirates.
Other ALG games I have tried the reload works fine (Crime Patrol 1+2, Mad Dog 2, Last Bounty Hunter). I have settings > input > port 1 controls > gun reload mapped to mouse 2 (pump action on my lightgun). I have also tried mouse button 3 and mapping either to AuxA to see if that made any difference, but it doesn't.
I am using lr-opera 1.0.0 3849c96 on a Pi4 running Retropie with RA 1.9.14. Port 1 is set to 3do lightgun.
One thing to note about Mad Dog McCree is on an initial load of the game I can shoot/reload on the main menu using the pump action, but in game it fires shots (same as the trigger/mouse 1). Once the .srm file is created, If I exit the game and start it again reload no longer works at the main menu, it instead fires shots.
Please let me know what additional details I can provide.
Side question: does opera support 2 arcade lightgun for arcade games such as Shootout at Old Tucson? I am able to get the game to run with 1 lightgun (which is detected and plays as player 2), but I am unable to get 2 lightguns to work. I can start a new thread for this if it is preferred.