Using own MP properties in Effects

[Necolatis]

Hello,

It seems we cannot use relative paths in effects the same way we can in animations, submodels and particles.

For example from a ALS thruster effect:

Code: Select all

<thrust_density type="float"><use>sim/multiplay/generic/float[9]</use></thrust_density>

Since there is no "/" in front of the property we would normally expect it to be relative from the MP property path for example to become:

ai/models/multiplayer[3]/sim/multiplay/generic/float[9]

Is there a workaround for this, or any chance this can be changed? (or is it just me that cannot get it to work?)

That would be very useful for ALS thrusters, ALS procedural lights and more, when viewing the aircraft over MP.

[Thorsten]

I'm not sure about anything MP in general, but my first suspicion if something works in animations but not in effects is that it ends up being a tied property and hence isn't picked up by the effect system (which relies on listeners firing).

In that case, it can be un-tied by passing it through a property rule with a gain of 1 and using the output of that - so if the strategy works otherwise for gear animation etc, I'd try that next.

[Necolatis]

Thank you for the reply. I have no clue what a tied property is though.

Okay, the problem is then that only a certain amount of properties is sent over MP. If they all is tied, whatever that mean, then I would not know how to solve it.

Any way to detect is a property is tied?

[AndersG]

IIRC the property browser can show tiedness (but not by default - the toggle is shift+click on the '.' entry or something similar?).

Another give away is to observe the property as it changes in the property browser - for untied properties the property browser uses a listener so the value updates immediately/smoothly while a tied property is refreshed X times a second (where X is rather small).

I think all MP properties are tied (by the MP data replay interpolators).

[Thorsten]

Any way to detect is a property is tied?

You can use it to update animations and see its value change, but it never ever has an effect on the effect system (pun intended) - that's my criterion.

Don't waste much time trying to find out whether it's really tied, pass it through something like

Code: Select all

 <filter>
   <type>gain</type>
   <gain>1.0</gain>
   <input>/fdm/jsbsim/systems/various/tied-property</input>
   <output>/fdm/jsbsim/systems/various/untied-property</output>
 </filter>


and pass the output to the effect, see what happens.

[Necolatis]

Thank you, will try something like that.