Beetle-PSX (mednafen_psx) lightgun support - #16170
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Enable support for lightguns in hardware rendering paths, and expose more of the available core specific options via libretroOptions.py. Add the missing mednafen_psx button-remap block in configureGunInputsForPlayer (parity with pcsx_rearmed) plus a gun_type == "justifier" override in the gun_mapping dict, so the real GunCon's 3-button hardware maps onto RetroArch's generic gun scheme instead of falling through to the fully generic default. That alone isn't enough: Beetle-PSX's GunCon/Justifier emulation is hardware-accurate and samples the actual rendered pixel color at the aim position each scanline to simulate the real light-sensor photodiode. That pixel buffer is only populated under the software renderer - under the HW (Vulkan/OpenGL) renderer this fork defaults to, the position never reaches the game at all. Fix via a new source patch, 002-guncon-justifier-hw-renderer-position-fallback.patch, touching mednafen/psx/frontio.c's two *_GPULineHook functions: when the pixel buffer is unavailable (HW renderer), skip the brightness-sampling loop but still set the hit position directly from the computed aim coordinates - the same "trust the raw position" approach pcsx_rearmed/swanstation already use, applied only when real light detection isn't possible. Software renderer keeps full authentic light-sensor behavior.
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@Tovarichtch , heres another light gun related change I'd like you to look at when you have chance, thanks! |
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I'm very busy with xemu Chihiro for the past month. I will get back to you once I'm finished with initial support and release of the first playtest. |
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Disclosure, this change was done with Claude.
Lightguns currently work when using the software renderer in Beetle-PSX, this change enable them in hardware rendering paths too, and exposes more of the available core specific options via libretroOptions.py.
For gun support:
Add the missing mednafen_psx button-remap block in configureGunInputsForPlayer (parity with pcsx_rearmed) plus a gun_type == "justifier" override in the gun_mapping dict, so the real GunCon's 3-button hardware maps onto RetroArch's generic gun scheme instead of falling through to the fully generic default.
That alone isn't enough: Beetle-PSX's GunCon/Justifier emulation is hardware-accurate and samples the actual rendered pixel color at the aim position each scanline to simulate the real light-sensor photodiode. That pixel buffer is only populated under the software renderer - under the HW (Vulkan/OpenGL) renderer this fork defaults to, the position never reaches the game at all. Fix via a new source patch, 002-guncon-justifier-hw-renderer-position-fallback.patch, touching mednafen/psx/frontio.c's two *_GPULineHook functions: when the pixel buffer is unavailable (HW renderer), skip the brightness-sampling loop but still set the hit position directly from the computed aim coordinates - the same "trust the raw position" approach pcsx_rearmed/swanstation already use, applied only when real light detection isn't possible. Software renderer keeps full authentic light-sensor behavior.
For extra options:
The extra options added have been grouped how they appear in the retroach core settings themselves, I've put the four new options under a "BEETLE SPECIFIC" sub header for clarity. See attached menu.txt file for reference on how they look in terms of layout.
menu.txt
Tested on X86 build with Sinden light gun.