Adusting fire effect

[trucker17]

I have to things i need to fix actually......
1st. is the fire effect from camp fires.....Can the size of the fire be adjusted to a small fire......
2nd. the smoke effect, is their a way i can delete the smoke or tone it down on the campfire.....

 

[L_Rob]

Perhaps I can offer a few suggestions: what you want to do is not hard once you understand the functions of the various parameters in the .fx file. I would suggest spending a little time with the SDK if you have not already done so; it will save a lot of time in the long run. For this sort of thing I think Arno's FXE is very helpful although the effect of adjusting alpha values (one way to tone down the smoke) in FXE does not match what you see in the sim that well, plus there is some difference between FSX and P3D. Alternately you can use FXTool which comes with the SDK. When using FXE or FSTool I think it's useful to disable all the emitters except the one you are adjusting. You can use // to do it, but remember to turn the emitter back on if you want it. (Who me, forget such a thing??) It's important to remember that many of the parameters are interrelated, and often just linearly scaling one value will not produce the effect you want. For smoke effects, the keys are scale, scale rate, scale goal, temp, temp rate and drag. (Jitter and rotation can be tweaked too if you want.) You may not need to adjust all of these, but it's useful to know what they do. One way to get a feel for what's going on is to compare some of the different default smoke effects, say with the compare plugin in Notepad++.

 

[GaryGB]

Some example info on adjusting the FSX default Campfire.Fx file ...that I posted a few years ago:

http://www.fsdeveloper.com/forum/threads/chimney-flare-effect.19315/#post-130613

http://www.fsdeveloper.com/forum/threads/model-with-effect-attached.19782/#post-130437



PS: Info on Arno's FXEditor (aka "FXE"):

http://www.scenerydesign.org/fxeditor/


Hope this helps !

GaryGB

 

[L_Rob]

Thanks for the links Gary,

Do you happen to have an updated one for this one you mentioned?
"Milton Shupe wrote an excellent tutorial on smoke effects including TempK / TempRate parameters (as related to aircraft exhaust) here: " http://www.aerodynamika.com/cgi-bin/yabb/YaBB.cgi?num=1197136310/2

Besides the info in the SDK and having a rough feel for what happens, I started wondering what the actual difference is between the effect of TempK and a y particle velocity. I did a few quick and dirty experiments with a test smoke effect that just emits a vertical stream of black dots. By taking a screen shot and measuring the location of the dots in pixels with PS then graphing the result, I came to the conclusion that TempRate causes a slowly decreasing vertical acceleration. I got a fairly good fit with a simple polynomial, but I'd really be curious to know how Arno implemented this parameter in FXE. The acceleration would make sense in that it would fit with the concept of what happens to a parcel of air as used in meteorology. I could illustrate the TempK effect by setting the value well above the nominal ~107 but shooting the particles straight down. The dots descend, slow down, stop, then start to rise slowly accelerating upwards. As for TempRate, it's tempting to think this might be a certain number of degrees per second; maybe I can check this too.

Now I'm curious about drag; there seem to be two likely possibilities; one is that it causes a deceleration that's approximately proportional to the speed (say like a friction force) or perhaps it's more like a squared function as might be used for aerodynamic drag -- if I remember correctly. I think I can use the same method above to find out.

 

[GaryGB]

Thanks for the links Gary,

Do you happen to have an updated one for this one you mentioned?
"Milton Shupe wrote an excellent tutorial on smoke effects including TempK / TempRate parameters (as related to aircraft exhaust) here: " http://www.aerodynamika.com/cgi-bin/yabb/YaBB.cgi?num=1197136310/2

Hi Larry:

I had to Google to find this link to Milton's original post (the server for the above 'CGI' link is apparently offline)

http://www.sim-outhouse.com/sohforums/showthread.php?58019-Start-up-Smoke-Effects


FYI: I had to leave out the Fx "TempRate" query string variable to get more (and FS-related) hits:

https://www.google.com/#q=Milton Shupe smoke effect TempK aircraft exhaust

NOTE: It is interesting that in the above post, Milton describes use of Effect positioning via Fx file "Offsets" ...instead of using adjusted Contact Points in a Aircraft / SimObject CFG file.


Additionally, I assume that Milton's statement in the above linked post at SOH:

"...you only need to be concerned with the offsets to those coordinates as specified in the effect itself:
X Offset=-0.810, -0.810
Y Offset=-0.110, -0.110
Z Offset=-1.250, -1.250"

...refers NOT to the Effect parameter for "visual" Offset in the FSX SDK Special Effect Tool 'Main' dialog:

"Offset
x,y,z

This allows the special effect to be moved from its actual position to a better position simply for viewing while being edited. The range of each of the options is -50m to +50m"


...but rather to the 'Offset' parameters in the Tabs / sections for Particles and/or Emitters under ex:

* Particle N tab

...or:

* Emitter N tab


Of incidental note is this statement under...

"Static=0/1":

"Particle offsets do not work on static particles, use emitter offsets instead."


Also, notable is that the "Offset" parameter works with the "Line Controller Effect Type-2"

"Type=0/1/2/3

Type=2 is the Line controller. This type was used to create the waves (using vector data as lines). The line controller uses the X, Y, and Z Offset described below."

https://msdn.microsoft.com/en-us/library/cc526969.aspx#TheFXToolDialog


PS: I stumbled across this in one of the Google hits; perhaps the "vapor" effects might also be something to check out ?


"FSX The LOCKHEED MARTIN F-16 Fighting Falcon (VIPER) by Kirk Olsson adapted to use in FSX by Danny Garnier"


"new AB, vapor and exhaust smoke effects finish the package. Aircraft model by: Kirk Olsson. Repaint: Claus Vendelboe Holmberg"


I'm not certain if the 'same' Effect set is in the intermediate version of the aircraft at this link:

http://www.flightsim.com/vbfs/fslib.php?searchid=36495927


[EDITED]

Also, I 're-discovered' yet another Fx-related positioning control option when Effects are placed relative to an object (my quote is from another thread linking to the URL below):

"Given some of the issues we are currently working through with undesired run time offset of displayed Effects (attached to MDLs or otherwise placed directly) relative to legacy FS 3D world model versus FSX P3D "curved earth" FS 3D world model and/or P3D Tesselation, batched texture draw calls etc., I found this 'brute force method' implementation of "<BiasXYZ" used for achieving specified placement of Effect lights interesting (...for at least a "temporary" workaround ? ):"

http://www.fsdeveloper.com/forum/threads/blinking-lights-timers.762/

[END_EDIT]


Hopefully through these inquiries the FS development community may achieve a better understanding of how to place and/or attach Fx files in scenery and/or in association with Aircraft / SimObjects with greater precision and predictability.

This would be very helpful to know more about, as we are still (9 years after the release of FSX) are sorting out desired versus un-anticipated "offsets" due to ACES undocumented and/or buggy calculations related to FS 3D world QMID Grid Latitude / Altitude / Earth Spheroid / MDL Attachment / DrawCall Batching intended to apply 'correction' in FX placement, (...but which variably seems to result in 'non-correction' of Fx placement when displayed in FS at run time ).


Hope this helps !

GaryGB

 

[L_Rob]

Thanks for all of this Gary,
I've done a few more experiments with some of the parameters and I'm hoping to write down my tentative conclusions. That is, if I can overcome the guilt for not doing each test at least three times and taking the average, and computing an error margin. Oh, yes, I guess I need to do it in FSX, P3D, and FXE. No wonder I never get anywhere.