[ATSF3751]

Hey everyone!

I just wanted to let everyone know that a small group of us are now helping Peter with steam locomotive testing and coding. I have started this forum to open up the discussion to others and so we can let everyone know what we plan to work on and get feedback.

Our first task is to work on oil burning steam locomotives. We plan to build a SP GS1 class 4-8-4 and do the testing with that class of locomotive to start. After we get an Oil Burning Eng and Tender file working the way we all agree with we will then work on other features that have to do with steam locomotives.

We plan to accomplish this by focusing on one thing at a time so we don't get too far ahead of ourselves. Peter felt it was only right to open it up to everyone for others that may want to get involved or have incite into coding and testing as we move forward.

Hopefully with a few of us working together this will speed things up for Peter and the steam coding so we can start focusing on other aspects of Steam Locomotives in Open Rails.

Feel free to chime in if you have any questions or suggestions for the ones who have teamed up with Peter.

Brandon​

[Jonatan]

I know oil firing is on the worklist now, but a future request in steam loco coding would be to have the water level fluctuate with grade and momentum. And more options for water feed.

I can give some personal experience input on these things if required, when the time comes.

[Traindude]

I have some ideas for improvements in regard to the ORTSWheelCrankAngleDifference and CylinderSteamExhaustFX parameters:

1. Currently, if a locomotive stops or stalls on a "dead center" with the throttle open, the CylinderSteamExhaustFX emitters will emit continuously until the wheels begin to turn again. This should be fixed so that the CylinderSteamExhaustFX "puffs" start at full velocity almost instantly, and slowly "fade out" within maybe 2 seconds depending on throttle and cutoff setting.

2. For use on geared locomotives (and steam booster engines), the parameter should be changed to ORTSCrankshaftCrankAngleDifference. This is then multiplied by the gear ratio to get the number of puffs needed for one wheel rotation.

3. If we want to model duplex and articulated locomotives in the future, it should be borne in mind that the two "engines" are often modeled as being rotated out of sync with each other. If we were to add independent wheel slippage for each engine, then an ORTSWheelCrankStartAngle parameter will need to be added to tell ORTS what angle the wheels for that engine will be when the shape file(s) are loaded. This corresponds to the angle of the wheel cranks in frame 0 of the wheel animation data. For example:

ORTSWheelCrankAngleDifference ( 0deg 90deg )
ORTSWheelCrankStartAngle ( 30deg 120deg )

4. Since the results of the puff timing are nearly flawless, it would be nice to have some new discrete sound triggers to be added so we get synchronized chuffs in perfect sync with the puffs!