Great idea Andy, I'll have to add that to my next round of effects for the Spitfire project.

Quote Originally Posted by AnKor View Post
This could potentially allow more complex conditions for enabling/disabling effects, but I haven't thought about it much and not sure what is possible and what is not. Are there any interesting effects which require additional conditions?
Well that's got the wheels turning. Give me long enough and I could think up a whole bunch of things. Here's a few off the top of my head.

Horsepower - useful for engine exhaust effects. Manifold pressure could work too, but horsepower would be ideal. Would be good if it could be used in conjunction with the high altitude sprites so contrails can be shut off when the engine is shut down or destroyed.

G forces - G-force induced contrails (combined with Andy's low altitude sprite trick if possible), smoke from negative-g carburetor flooding that certain aircraft experienced (best if paired with horsepower for the same reason as the high altitude sprites).

Mach (as opposed to airspeed) - sonic booms, etc.

Altitude above ground - would be useful for dust effects as pictured above, would be good if it could differentiate between land and water to allow different effects. Think of flying at wave top height and kicking up a spray!

Rain - wet cockpit windows (that might be a long shot)

Rounds remaining in a given gun - could turn on tracers the last few rounds as was often done to let the pilot know he was almost out of ammo.

No idea how feasible any of that is, but a lot of those have been things we've beat our heads against for years.