Board index FlightGear Development Effects and shaders

transsonic cone with ALS

An exciting "new" option in FlightGear, that includes reflections, lightmaps, the particle system etc.. A lot is yet to be discovered/implemented!

transsonic cone with ALS

Postby hardba11 » Wed Feb 01, 2017 1:10 am

Hello !

Image

Did anybody ever try to create a transsonic cone with ALS ?
Does an als-specific shader exists ?
I created a bounding box (a Cone) an tested the shader "thrust-flame" in it ... no comment ;)


Thanks for your answers :)

Nico
contribs: mirage2000-5, statics models, LFRV - WIP: new aircraft, TFFJ - hobby: world tour in flightgear
hardba11
 
Posts: 148
Joined: Tue May 27, 2014 5:56 pm
Location: Paris - FR
Callsign: F-HRDB
Version: 2018.2.3
OS: windows and debian

Re: transsonic cone with ALS

Postby Thorsten » Wed Feb 01, 2017 12:09 pm

We do not have a special-purpose shader for that one (or add a parameter to make the flame shader do it, it's mainly in the spread dynamics I think) - commonly I see this modeled via particles (though they're evil).

So I guess I'll take this as a feature request and add it to my to-do list.
Thorsten
 
Posts: 9530
Joined: Mon Nov 02, 2009 8:33 am

Re: transsonic cone with ALS

Postby hardba11 » Wed Feb 01, 2017 4:23 pm

thanks for your answer Thorsten,

it was just a question so no urgency for the feature.
I will wait ;)

cheers

Nico

Image
contribs: mirage2000-5, statics models, LFRV - WIP: new aircraft, TFFJ - hobby: world tour in flightgear
hardba11
 
Posts: 148
Joined: Tue May 27, 2014 5:56 pm
Location: Paris - FR
Callsign: F-HRDB
Version: 2018.2.3
OS: windows and debian

Re: transsonic cone with ALS

Postby wlbragg » Wed Feb 01, 2017 11:20 pm

t was just a question so no urgency for the feature.
I will wait ;)

cheers

Nico


Referring to the picture, unfair, talk about incentive, ha! :lol:
Kansas(2-27-15)/Ohio/Midwest scenery development.
KEQA (2-27-15), 3AU, KRCP Airport Layout
User avatar
wlbragg
 
Posts: 3982
Joined: Sat Aug 25, 2012 11:31 pm
Location: Kansas (Tornado Alley), USA
Callsign: WC2020
Version: next
OS: Win10/Debain/nVGT640

Re: transsonic cone with ALS

Postby yanes » Thu Feb 02, 2017 12:19 am

It's already modeled by FGUK members (not sure !) i their su-27 , su-37 ..., the su-27SK look in "Models/effects/boom/"
It doesn't refer to ALS, but looks pretty and it's ready for use .
And BTW, Thank you ,as mirage-2000 developer your work (and SHINOBI as well )was a great help for me .

Image
Image
Last edited by yanes on Thu Feb 02, 2017 12:22 am, edited 1 time in total.
User avatar
yanes
 
Posts: 102
Joined: Tue Sep 02, 2014 1:14 pm
Location: Tunisia
Callsign: YANES
Version: 2017.4.0
OS: Linux

Re: transsonic cone with ALS

Postby PINTO » Thu Feb 02, 2017 12:21 am

No offense to anyone, but that just doesn't look that good.
Actively developing the MiG-21bis (link to repo) (link to thread)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 911
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: transsonic cone with ALS

Postby yanes » Thu Feb 02, 2017 12:25 am

:D :D
May be not the best but it shows something that refer to reality ,
I think it needs just a bit of improvements
User avatar
yanes
 
Posts: 102
Joined: Tue Sep 02, 2014 1:14 pm
Location: Tunisia
Callsign: YANES
Version: 2017.4.0
OS: Linux

Re: transsonic cone with ALS

Postby Thorsten » Thu Feb 02, 2017 6:36 am

think it needs just a bit of improvements


The thing with objects that don't have an 'edge' in reality (clouds, vapour, flames,...) is that you can model them as a mesh, but there'll always be an edge and there's no 'bit' of improvement you can do on them.

Getting diffuse edges in rendering is a moderately tricky task and you have to design your strategy to do it up-front.

There's several 'cones' modeled as 3d meshes for various aircraft (Vostok-1 also has one) - and sometimes there's particles for the task (which at least are blurry).

Also, if you look at movies of the real thing, it often has a very flickering quality to it.
Thorsten
 
Posts: 9530
Joined: Mon Nov 02, 2009 8:33 am

Re: transsonic cone with ALS

Postby erik » Thu Feb 02, 2017 7:56 am

The F-16 has something similar (but not the transonic cone yet) using the exhaust flame effect and it has the 'flickering quality':
Image

Erik
erik
 
Posts: 1495
Joined: Thu Nov 01, 2007 1:41 pm

Re: transsonic cone with ALS

Postby hardba11 » Thu Feb 02, 2017 9:06 am

hello

wlbragg wrote in Wed Feb 01, 2017 11:20 pm:Referring to the picture, unfair, talk about incentive, ha! :lol:

:lol: you're right wlbragg ! I hope Thorsten will find this picture more incentive than unfair ;)

yanes wrote in Thu Feb 02, 2017 12:19 am:It's already modeled by FGUK members (not sure !) i their su-27 , su-37 ..., the su-27SK look in "Models/effects/boom/" It doesn't refer to ALS, but looks pretty and it's ready for use .

thank you yanes, a .ac semi transparent is one of the solutions (the other are the particles but are no more recommended) but ALS will always give something very more beautiful :D

erik wrote in Thu Feb 02, 2017 7:56 am:The F-16 has something similar (but not the transonic cone yet) using the exhaust flame effect and it has the 'flickering quality'

It looks good. How did you manage to disable the luminosity of the flame effect ?


cheers
Nico
contribs: mirage2000-5, statics models, LFRV - WIP: new aircraft, TFFJ - hobby: world tour in flightgear
hardba11
 
Posts: 148
Joined: Tue May 27, 2014 5:56 pm
Location: Paris - FR
Callsign: F-HRDB
Version: 2018.2.3
OS: windows and debian

Re: transsonic cone with ALS

Postby erik » Thu Feb 02, 2017 9:27 am

The effect allows you to control almost any aspect of it. The hardest part was finding a suitable bounding box that doesn't intersect with the fuselage (although it inevitably does at the front).

See: Aircraft/f16/Models/Effects/strake-vortex.eff

Erik
erik
 
Posts: 1495
Joined: Thu Nov 01, 2007 1:41 pm

Re: transsonic cone with ALS

Postby hardba11 » Thu Feb 02, 2017 9:44 am

thank a lot Erik
contribs: mirage2000-5, statics models, LFRV - WIP: new aircraft, TFFJ - hobby: world tour in flightgear
hardba11
 
Posts: 148
Joined: Tue May 27, 2014 5:56 pm
Location: Paris - FR
Callsign: F-HRDB
Version: 2018.2.3
OS: windows and debian

Re: transsonic cone with ALS

Postby Thorsten » Thu Feb 02, 2017 10:56 am

Erik, since you have some experience with this already - what would this need to render a decent cone? Is is just the expansion (the flame has a parabolic profile, whereas the cone is linear,...), would we need something more?

And is there anything that'd make the bounding box issue easier?

How did you manage to disable the luminosity of the flame effect ?


You feed a property instead of a value which changes with ambient light - it's mentioned in the Wik how to set this upi.
Thorsten
 
Posts: 9530
Joined: Mon Nov 02, 2009 8:33 am

Re: transsonic cone with ALS

Postby erik » Thu Feb 02, 2017 1:10 pm

One thing which might make the bounding box issue easier is to be able to set the top-down center position within the box: for example 0.5 originates at the center of the up-down axis which represents the current behavior.

0.0 or 1.0 would then position the center at the top (1.0) or at the bottom (0.0), creating an asymmetric effect. The left-right position and front-back position would remain the same. That would be really nice to have and could solve most of the intersection problems. But not for the transonic cone I'm afraid. For that it might me required to define an inner tube with a particular diameter which is unaffected by the effect.

Edit: By the way I wouldn't mind if the effect just gets clipped at he edge of the bounding box, I don't think it is necessary to create an asymmetric visual effect where one side is compressed and the other expanded.
erik
 
Posts: 1495
Joined: Thu Nov 01, 2007 1:41 pm

Re: transsonic cone with ALS

Postby erik » Fri Feb 03, 2017 12:37 pm

I was thinking: if the cylinder is too difficult to implement it would be easy the simulate the same effect with two bounding boxes (one above and one below the aircraft) if the asymmetric part is implemented.

Erik
erik
 
Posts: 1495
Joined: Thu Nov 01, 2007 1:41 pm

Next

Return to Effects and shaders

Who is online

Users browsing this forum: No registered users and 1 guest