[rdamurphy]

Actually, in another related thread, I noticed an error in the Steam code for steam generation. After fixing it, the steam/smoke effect improved immensely...





Robert

[_o_OOOO_oo-Kanawha]

Smaller puffy balls I see in the picture? What smokemain.ace? Has it been committed to a daily build yet? I still have larger puffy balls in v1771 using smokemain.ace 12/8/2005, of which I don't know wether it is the original from MSTS as its file stamp is much later.

[rdamurphy]

_o_OOOO_oo-Kanawha, on 24 September 2013 - 10:17 AM, said:

Smaller puffy balls I see in the picture? What smokemain.ace? Has it been committed to a daily build yet? I still have larger puffy balls in v1771 using smokemain.ace 12/8/2005, of which I don't know wether it is the original from MSTS as its file stamp is much later.

I have 5.7.2001 on my smokemain.ace. This is from v1773, after I committed a fix for the steam usage, that the particle emitter depends on...

Robert

[_o_OOOO_oo-Kanawha]

OK, understood. I am now on v1773 as well and it seems the exhaust responds betters to the throttle. It darkens and lightens as well with firing I think, when watching the F5. Haven't tried manual firing yet to get some really dark smoke.

So if I understand correctly, the fluffy balls from the smokemain.ace now act like particles in your implementation?

[rdamurphy]

_o_OOOO_oo-Kanawha, on 24 September 2013 - 10:37 AM, said:

OK, understood. I am now on v1773 as well and it seems the exhaust responds betters to the throttle. It darkens and lightens as well with firing I think, when watching the F5. Haven't tried manual firing yet to get some really dark smoke.

So if I understand correctly, the fluffy balls from the smokemain.ace now act like particles in your implementation?

Not particles exactly, but yes, they're double sided quads. They have a certain random effect to them, so that they rotate and some of them go slightly off-center. It wasn't visible because the old particle effect didn't set both parameters required, and used the default for one of them. So, there was only a small amount of change. Meaning there were WAY too many particles, and they overlapped each other to the point none of them were visible.

The current implementation varies both the number of particles and the height of the plume, along with variable color from 1,1,1 all the way to 256, 256, 256 based on a mixture of the smoke color and the steam color (pure white). Although there's another slight tweak I want to add, to make the color more "centered". I'm still thinking about how that's going to work...

I agree, the locomotives definitely respond better, although it's hard not to "jackrabbit" on starting, since, like helicopters, steam has a slight lapse in response after control movement.

Another slight tweak I intend, no steam even when the throttle and cutoff are open if there's no motion forward or reverse. Definitely need to fix that, I think? If an exhaust port is open in one of the four chambers, there has to be a certain amount of steam on both the cylinder cocks and the stack, correct?

Robert

[_o_OOOO_oo-Kanawha]

I suppose there is no exhaust when the pistons don't move, since there is no path between in the inlet and exhaust ports of the cylinders.

Real locomotives have a blower, that is usually on when standing still to provide draft and to keep the flames from leaping out through the firehole if the firedoor is opened. So some light grey exhaust could be OK to simulate that when there is no separate blower control in manual firing mode.
Real locomotives's cylinder cocks only emit steam if the throttle is cracked open just a little. At least I have my steam locomotives in Railworks configured that way.

The plume's top is rather abrupt and bobs a little with small throttle settings, but until a proper decay or dissolve of the 'particles' can be provided, there is little to be done about this.

So far this is looking OK. Full steam ahead, Sir!

[copperpen]

If the engine is not moving there will be no steam through the cylinders. However, when at a stand the blower is usually operating to maintain a healthy draft through the firebed. When the forward motion starts, you will not see the big exhaust until the cylinder/s get to the point where the exhaust port is open. Even if the engine comes to a stand with the exhaust port open, there will be no steam from the cylinder because there is no motion to push it out of the cylinder.

[SVRy_Steve]

Something to remember, the blower was used on oil fired engines when standing, to increase the draft, but coal fired engines rarely used the blower. When standing, other than the occasional sound of the air pump and injector, they quietly simmer and have essentially no exhaust smoke or steam.

Another thing many engines had was some form of cyclone front end or other device to pulverize coal embers by centrifugal force. These imparted a swirl to the exhaust, something that would be very hard to duplicate in the sim!

Steve

[CrisGer]

Agree with all comments here...i tested it last night and there is definite improvement, there is a smoke plume instead of a blob balloon. There is also response to changes of engine movement and firing, i tested both manual and automatic. Next will be getting the smoke plume to have more volume more of a horizontal cylinder that varies in height and size and rotates also with variations. That was the key to the original MSTS smoke working well once we had a decent set of frames for the image change but you have clearly broken the barrier and are making huge progress, well done!

[rdamurphy]

The diameter of the plume is taken directly from the .eng file, I'll compare the loco in MSTS and OR and try to add a "fudge factor" to make them the same in both sims. This should affect both diesel and steam.

Also, there's an error that I know needs fixed. I need to adjust the mixture, so, if for instance, the plume is 30% steam and 70% smoke, the color will be 30% steam color and 70% smoke color. It basically does that, but not precisely, it's an approximation, and it tends to lean a bit much towards steam color.

BTW, the plume color is dynamic, it can be anything from white to any color of grey to black, or anything in between.

I'm glad everyone likes it!

Thanks so much for the compliments!

Robert