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[WxTech]

I've got back to looking into at incorporating the use of so-called '3D' tracer smoke effects, for at least one of the effects. The original, and still by far the most commonly used type is that based on the TSmokeTrailParams class, as opposed to the TParticlesSystemParams class. The former are commonly called '2D' smokes, being a continuous trail of joined textures into a 'ribbon' which always faces the viewer. The latter are the '3D' particle based effects comprised of discrete, separate textures, and which look more natural in almost all instances.

The problem with the '3D' smokes is that they almost always require to generate a very much larger number of individual particles in order that there be no excessive space between them; the continuous trail type can be made to require a quite small number of elements.

The common tracer smoke effect that's 'converted' as such is "3DO/Effects/Tracers/TrailCurved.eff". I have seen one other '3D' tracer smoke effect assigned to just one gun. Otherwise that's it.

I've just started to add new code to Gun.class which differentiates between the player's plane and AI planes. The idea is to have any '3D' tracer smoke created only for the player's plane, which would save on resources if there are a number of AI planes close together and firing a bunch of guns at the same time. And given that their smokes are mostly seen from angles other than end-on, the more continuous trail looks better than the '3D' type whose individual particles are pretty widely separated. In other words, the '3D' smokes would be utilized where the player will be seeing them almost exclusively from an end-on or nearly end-on perspective.

Perhaps I'll build in the ability to choose their use via a conf.ini control. This would obviate any need to manage mod folders.

I'll soon be able to test this out and report back...

So, back to the question: Do you use any '3D' tracer smoke mod already?

[FL2070]

I do, and have been for years. After a bit of tinkering, all the issues with particle spacing and number can be (mostly) ironed out—the trick is to make sure they retain the velocity from the bullet they're emitted from, so that they don't get so spaced out from the low number of particles required to prevent overstressing the effects engine. But even if I couldn't get 3D smoketrails looking quite right, I'd still use them any day over 2D ones. I just hate that star-effect that happens when you get too close to a 2D trail. I can't live with it.

[WxTech]

I'd be curious to see one of your .eff files. Here is one of mine.

I have the far distance limit at 1200m in the .mat file. I have gasResist set to 0.3 so that the smoke particles decelerate very quickly. At a smaller value of, say, 0.1, they retain some of the bullet velocity for a while before slowing down in the slipstream. The result is that initially the smoke particles are moving faster than my plane for perhaps a half second, then start moving aft at an increasing rate.

To be sure, if one's plane has numerous guns, such as the Spit I's eight .303s, holding the trigger for a bit so that many particles are being generated will cause some disappearance of other effect particles. 

[ClassInfo]
  ClassName TParticlesSystemParams
[General] 
  MatName ../TEXTURES/TrailCurved_3D.mat   
  Color0 0.66 0.69 0.73 0.3
  Color1 0.66 0.69 0.73 0.0
  nParticles 265
  FinishTime 1.2
  MaxR 0.1
  PhiN 0.1
  PsiN 1
  EmitFrq 220
  EmitVelocity 4 8
  EmitTheta 60 90
  Wind 0
  Size 0.15 1.5
  GasResist 0.3
  VertAccel 0
  LiveTime 1
  Rnd 0.3

[WxTech]

The inherent difficulty of obtaining a halfway decent smoke trail composed of a string of discrete particles sure makes it hard to adopt the scheme, for even just the player only.

When pulling a turn while firing, the trail shifts laterally due to the plane continually turning away from the bullet flight path. This really makes evident the large gaps between particles. (Things are OK if the turn is relatively gentle.) How to overcome that? It requires to employ 'tricks' which suffer their own disadvantages.

One approach is to set a small value for GasResist. This will keep the particles more closely bunched together for a longer spell due to requiring some interval of time to decelerate. But then the smoke particles will initially be traveling faster than the plane, a most disconcerting sight. And for a given number of particles the trail will be shorter. It would require to generate yet more particles to get the trail length increased, which only compounds the problem.

On balance, the choice comes down to this. Does one want tracer smoke trails to last at least long enough to suggest smoke that hangs about for a little while, or is one content to have an appearance more resembling quickly evaporating steam?

In my own best compromise, where a tracer smoke trail has about the same number of particles as a plane's damage smoke trail, or around 250), when several guns are firing and hence something like a dozen tracer trails are in process of generation, the game engine is very likely to hit limits, with other effects going invisible. For instance, if my Bf-110 victim has a couple of fires and a few damage smokes occurring, when firing my 8 guns for longer than about a second, and thus getting the tracer trail count up there, it's not uncommon for all the fire and smoke effects to disappear briefly. That alone is a far worse outcome than suffering the artifacts of the simple '2D' smoke trail representation.

[FL2070]

I'd be curious to see one of your .eff files.

See here: https://www.sas1946.com/main/index.php?topic=71853

[carsmaster]

I've got back to looking into at incorporating the use of so-called '3D' tracer smoke effects, for at least one of the effects. The original, and still by far the most commonly used type is that based on the TSmokeTrailParams class, as opposed to the TParticlesSystemParams class. The former are commonly called '2D' smokes, being a continuous trail of joined textures into a 'ribbon' which always faces the viewer. The latter are the '3D' particle based effects comprised of discrete, separate textures, and which look more natural in almost all instances.

1.Where are the classes files ??(folder ?? version game ??)

  TSmokeTrailParams class
  TParticlesSystemParams class

2. This default class files ??

More precisely, I'm interested in the Java code: .."being a continuous trail of joined textures into a 'ribbon' which always faces the viewer"

[WxTech]

When I wrote that the trail type effects always face the viewer, I should have been more specific.

The more correct way to express this is that each element making up the continuous trail is rotated so that it presents the maximal subtended area for its orientation. If we look at a curving trail from nearly end on, subsequent elements are differentially rotated as necessary to obtain this condition. At the join between any two parts, there is a discontinuity, or 'break' whereby the ends contact only at the center point of the edges in contact. Such a trail as seen roughly end on and arcing on projection upon the plane of the screen presents as a kind of 'Starburst.

All this is a consequence of the necessity of keeping the trail as presenting the fullest width possible. If a trail type effect were constrained to a fixed orientation in 3D space, at certain viewing angles it would disappear due to the flat object being seen edge on.

Particle type effects don't suffer this artifact because each is completely independent; they are not limited by being joined together into a contiguous string. All are always drawn in a face on orientation, rather like sprites.

[carsmaster]

When I wrote that the trail type effects always face the viewer, I should have been more specific....

Thanks for the answer.

Where are the classes files ??(folder ?? version game ??)

TSmokeTrailParams class
TParticlesSystemParams class

[WxTech]

I've never seen those classes. I wonder if this is yet more game resources buried in a .dll?