| From: Ant | 6/05/99
15:53:49 |
| Subject: Videogame Guns | post id:
9995 |
| How does a light gun on a home
console(like a playstation) work - how does it know where you're aiming on
your TV screen if the only link is a regular coax cable? Any
clues? | |
| From: Chris W (Plebeian) | 6/05/99
16:00:26 |
| Subject: re: Videogame Guns | post id:
9996 |
| The gun is a light sensor. When
you pull the trigger, the screen goes blank everywhere except where the
'bad guys' are (for one frame, about 0.02 secs). If your gun is pointing
at the bright spot a signal is sent to the console and a hit is
registered. If it pointing at a dark area no signal is sent, and a miss is
registered. | |
| From: Richard | 6/05/99
16:18:26 |
| Subject: re: Videogame Guns | post id:
10001 |
| Ant, The video gun that you are refering to has a light sencer in the end of it. This in most cases is a varient od the common diode or a light dependant resistor. The way this work is quite cool (I think) Basicaly when you pull the trigger on the gun the "game boy" or "PC" etc etc will do 1 or 2 paints on your screen (so fast you can't see it) This paint or picture will most likely be all black (which makes it harder for you to see) with the intended target in white. If the gun is pointing at the white bingo you got your target. | |
| From: Adam | 6/05/99
17:29:30 |
| Subject: re: Videogame Guns | post id:
10012 |
| I thought it captured where the
electron gun of tv was up to. If you look at a playstation gun (the namco
one) it has a lead which plugs into the video out of the playstation, so
the gun knows where the raster (electron gun)is up to. I've got one and I
recently upgraded from a normal 50Hz (I think) TV to a 100Hz Model. So
Basically its screen refresh is twice as fast. My gun now doesn't work!!!
It jumps all over the place, from bottom to top, left to right,
everywhere!! I was told it was because the gun wasn't finding the electon
gun where it was supposed to be and was adjusting. All due to the refresh
rate of the new TV, still works fine on the old one though. Thats how it
was explained to me and it sound
reasonable. | |
| From: MichaelT | 6/05/99
17:37:09 |
| Subject: re: Videogame Guns | post id:
10016 |
| Sorry Pleb, I have to disagree
with you there... A TV screen draws the picture, line by line from the top left corner. It actually draws every second line then goes back to the top and draws in the lines it missed out in the first path. (You will notice that fast photos taken of a TV will show only bits of the picture, the bits of the screen that were being drawn while the shutter was open) When you pull the trigger on the gun, it looks at the TV screen and notices when it sees the electron beam. The machine knows exactly where the screen is currently drawing, so can work out where the gun is currently pointing. (at least this is the way the games did it in TimeZone, where I was a technician foe a couple of years :) This is the basis of the 'light pens' of the '70s era. Regards, Michael | |
| From: Chris W (Plebeian) | 6/05/99
17:59:00 |
| Subject: re: Videogame Guns | post id:
10022 |
| I think you describe another
perfectly feasible solution provded the gun's sensor is sufficiently
sensitive to pick out a single pixel on a target that might be completely
BLACK (IE no electrons). How does the gun function then? I guess you could
ensure that your target was predominantly brightish colours and that the
gun averaged a whole chunk of them, but that would trigger anywhere the
phosphors had not died back to black. I described functionality based on the only direct experience that I have. Atari 2000 machines of similar vintage. We video taped the game to prove the point. | |
| From: MichaelT | 6/05/99
18:22:54 |
| Subject: re: Videogame Guns | post id:
10027 |
| Oh - I forgot to mention that on
the arcade games, the screen flashes when you press the trigger
:) I assume the computer knows for every frame the correct coordinates of the target. Regards, MichaelT | |
| From: Dana | 13/09/99
12:42:03 |
| Subject: re: Videogame Guns | post id:
37210 |
| >I thought it captured where
the electron gun of >tv was up to. If you look at a playstation gun
>(the namco one) it has a lead which plugs into >the video out of
the playstation, so the gun >knows where the raster (electron gun)is up
to. This is the same explanation I ha back when I used a lightpen on the Commodore 64... which definitely didn't need to flash the screen or make some bright spot for the lightpen to 'find'. It's the same explanation given in the C64 user manual too. Dana (showing my age and geekiness... and loving it :) | |