Ps1 Lightgun


Shaun

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I'm not sure if this has been asked before, but has a developer thought about implementing lightgun support with use of the touchscreen? This would be very cool for games like Point Blank or Time Crisis. ;)
 

notaz

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PCSX doesn't seem to have support for this, I need either the tech details or some opensource input plugin that supports this. It would help if someone researched this for me.
 

TitanUranus

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How did the PSX light gun work? I remember the Amstrad CPC light gun just flashed a white block onscreen where the target was and if the light gun was pointed at the correct source it picked up the light and gave you the points/hit. I suspect the PSX was a little more advanced than that :D

If however it was just the block of light perhaps you could just have the emulator check if the pixels at the co-ordinates pointed to by the stylus are lit up or dark and give the appropriate response to the input. I'll stop talking now as I'm almost certainly talking irrelevant bollocks.
 

DavidBowman

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wally said:
@gruso.. Die Hard Trilogy didn't use the light gun!

Actually, it does! It made Die Hard 2 much more fun, which is one of the reasons I bought one. I still have both my original DHT disc and my light gun.
 
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fearofshorts

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Personally, I think this should be entirely possible. I mean, they're the same type of input. It's not like we're facing that Amiga problem with relational movement.

Of course, that doesn't make it easy. Or guarantee that someone will want to make it. Still, I would personally love this.
 

Wally

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David Bowman said:
wally said:
@gruso.. Die Hard Trilogy didn't use the light gun!

Actually, it does! It made Die Hard 2 much more fun, which is one of the reasons I bought one. I still have both my original DHT disc and my light gun.

Wait.. so after all these years i've used the controller for nothing? D:
 
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Chaser

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TitanUranus said:
How did the PSX light gun work? I remember the Amstrad CPC light gun just flashed a white block onscreen where the target was and if the light gun was pointed at the correct source it picked up the light and gave you the points/hit. I suspect the PSX was a little more advanced than that :D

If however it was just the block of light perhaps you could just have the emulator check if the pixels at the co-ordinates pointed to by the stylus are lit up or dark and give the appropriate response to the input. I'll stop talking now as I'm almost certainly talking irrelevant bollocks.

Of no use to notaz but wiki covers the operation of all the guns.

http://en.wikipedia.org/wiki/GunCon ("The Guncon controller (known as G-Con 45 in Europe) uses the cathode ray timing method to determine where the barrel is aimed at on the screen when the trigger is pulled.")

http://en.wikipedia.org/wiki/Lightgun (lists how various models all worked)

There's something of an old discussion here http://hkems.proboards.com/index.cgi?board=general&action=display&thread=227 between an input plugin writer and a gun company regarding PS2 emulation but it seems most of the tech specs are probably proprietary secrets and not open source. I dont even have the google fu to know where to start looking though, so will likewise shut up.

Of note though DHT 1 works nicely on PCSX and is quite playable on the d-pad, as is TC 1, though 2 doesn't register hits and in r6 now runs like treacle.
 
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Dunny

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Just like the way the old Amstrad CPC light guns worked (and according to the wiki article cited previously), the PS1 lightgun probably looked at the screen and determined if a bright point (the phosphor dot) is visible while the trigger is depressed. If it is, then it's a hit. If not, then ... well, not.

When emulating a system like the Amstrad (or the ZX Spectrum, as I did) the display is likely tied into the CPU emulation quite closely, and so when an event occurs you can usually determine pretty easily where the phosphor dot should be - it's usually at the point you're rendering the display if you're rendering at the individual T-State (microcode stage) level. All I had to do was set the trigger port to return the correct value if the virtual phosphor was within a few pixels of the mouse pointer.

When emulating the PSX, it might be quite hard to determine exactly where the phosphor should be - emulating a system of that complexity to that level of accuracy just isn't worth it most of the time, so I would imagine that you build your frame of graphics and output it at the end of the frame. Throwing OpenGL into the mix probably makes it even harder to know just where you are within the frame. The dynarec won't help either - you'll have to store how much virtual time each block of executed code will take, and when the trigger goes down add them all together to see where you are in the screen...

Do-able, but very very complex I would imagine.

D.
 

jottt

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All of the common lightguns I met so far where depending on cathode ray tubes for orientation. Wikipedia explains nicely why. They do not work with LCDs. So I highly doubt this will be possible to implement on software side (because otherwise, it would have been done before for the big screens long ago). What might be possible to implement is this: http://www.lightguninfo.de/lightgunreview.php?idlg=16 as far as this review goes it already works with mame. However I am not really sure if it really makes any sense or works with a 7" screen ;)
 

Dunny

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jottt said:
All of the common lightguns I met so far where depending on cathode ray tubes for orientation. Wikipedia explains nicely why. They do not work with LCDs. So I highly doubt this will be possible to implement on software side (because otherwise, it would have been done before for the big screens long ago). What might be possible to implement is this: http://www.lightguninfo.de/lightgunreview.php?idlg=16 as far as this review goes it already works with mame. However I am not really sure if it really makes any sense or works with a 7" screen ;)

I'm fairly certain that the intention would be to use the mouse (AKA the touchscreen) as the lightgun, rather than using a real lightgun on the pandora. That would be silly!

D.
 
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Chaser

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Bummer I was hoping to scare my Pandora with the SuperScope and Menacer personally, I thought that's why it could sit at 90 degree laptop style so I could shoot at it from across the table with binoculars strapped to my head to feel like a virtual boy again :)
 

Prometheus

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Well, there's always the Ultimarc AimTrak kit, which by my understanding actually simply functions like a mouse. If mouse-light-gunning were implemented, and worked with external mice, you'd be able to fit this into any suitably-sized light-gun of your choosing and actually use a light-gun with the Pandora. :p

Silly, yes, but actually possible.
 

DavidBowman

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Ultimarc makes good stuff, and the owner is very helpful. I have a key encoder from him that I used in my MAME cabinet.
 

notaz

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I now have a real PSX with everything needed to run custom code on it, so if anyone has one of those lightguns and wants to send me one I could likely figure out how it works and add support for it.
 

Chaser

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Looks like its not to pricey to send something from the UK to you, so I've a bunch of 1st and 3rd party PSX guns I could send over if they're of use? I would love to see touchscreen implemented for the lightgun games like Pointblank, would be great time killers :) PM an address if your interested.
 

Lobo

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Dont forget you will need an old CRT TV to use the lightgun, they dont work on LED, LCD or Plasma.
 
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