Water Stream Particles

#1 I'd think using fast-firing projectiles with particle trails would be the way to go.

#2 Yes. Projectiles all the way. Each nozzle could be mapped to a different keyboard number. So instead of assigning 1 to Pistol and 3 to shotgun (or whatever), you could have them set to mist, stream, spray, pulse, etc.

Basic Bob had some water spraying capabilities if I remember correctly. You might want to check it out. Chris LaBombard made that game.

#3 Thanks ! I'm going to try the projectile then. This is why it's great to ask before attempting something.

#4 Water is a constant thing, and projectiles are... not so good for being used constantly. I'd see if using a combo of container raycasts/radiussearches or maybe a mounted trigger of some kind would work. Combined with just standard particle systems of course, which I think would give much better visual results if used properly. The only reason I'd use projectiles, is if you need the ballistic and gravity arc for spraying water over a long distance. Even then you'll probably need to modify the particle or projectile effects system to get anything decent looking. I heard the spline code for making arcs of lightning in T2 is still floating in the engine somewhere, that might work for an arched water spray too.

So yeah... I'd experiment with different things, depending on what type of water spray you're looking for. Long distance streams would be better for projectiles, and localized area sprays for particles and some other method.