The rules stay in TrackUneven.h with no dependence on the engine, as they can
be tested. Their use on the tracks moves out of Track.cpp to TrackUneven.cpp,
split into steps: the group of switches, the values of its paths, the meeting
of two ends. One set of helpers for the paths of a track takes the place of
the same conditions written out in several places, and the value at the ends
of a switch is worked out in one place. The clatter of an axle leaves the long
Update of a vehicle. The fields in the editor say themselves when they show.
No change in behaviour.
- A path of no length gave a joint with a vector across of NaN to the path
joined to it, on any scenery, with unevenness or not. It now has no
vector across, and so makes no joint.
- Axles no longer stray along the track. It moved vehicles against each
other, changing the distance their couplers go by.
- The bend under an axle goes straight on past the ends of a path: the
polynomial ran off on a short curved one, with a kick in the cab shake.
- A track left out of its rail run, where tracks are joined one way only,
no longer walks the whole run again on every call.
- The clatter of an axle goes by the outer axle on its side of the vehicle,
and not always by the same one, as the two can be on different tracks.
- A vertex works out the amounts once, and the foot of the ballast not at all.
On such a track the sway drawn from the lateral acceleration, that is
from the curve radius, and the jolts drawn at random are off. Tracks
with no unevenness shake the cab as before. Hunting stays: it goes by the
vehicle and its speed, not by the track.
The phase of the rails was wrapped to the rail length of the track the
vehicle is on, while an axle can be on a track with longer rails. From
then on every frame looked like a joint crossed.
Usage, optional attributes of a track entry, before endtrack:
uneven <mm> peak deviation of a rail on a 10 m chord, 0-100; normal and switch
unevenup <mm> up and down alone, instead of uneven; normal and switch
unevenside <mm> sideways alone, instead of uneven; normal and switch
unevencross <mm> cross level alone, instead of uneven; normal only
jointdip <mm> depth of the dip at rail joints, every sound distance; normal only,
default 0.4 of the up and down component
Values of uneven follow PLK Id-14 appendix 1: 6 mm is the limit at 160 km/h, 10 at 120,
18 at 80, 35 at 40; half of it for a track in a good state. Example:
uneven 18
unevencross 25
jointdip 6
endtrack
The same fields are in the editor, track panel, section Ride and sound. See
track_uneven_doc.md.
The unevenness is a displacement field over the plan of the scenery, with no random
numbers: one place strays the same every time, and joined tracks, the paths of a switch,
sleepermodel and axles at one place move together. Tracks meet at a joint at the lower of
their values. Joined switches take the lowest of theirs, the tracks joined to them come to
it, and a track with none of a component keeps the switch to its design in it. The clatter
comes from the dipping joints. Curve radius and grade for the physics stay as designed.
Tracks with it get geometry every 2 m on straights: 4x the vertices on Baltyk with all
tracks flagged, 0.2 ms more per frame on td.scn.
The dumb3d->glm / utilities-simplification refactor replaced the old custom
clamp() (which tolerated Lo>Hi, returning the upper bound) with std::clamp,
where inverted bounds are undefined behaviour. Only a few sites were patched
afterwards, by hand, with std::minmax plumbing (incl. a stray `static` inside
a per-axle loop). Others silently produced wrong results in the AI braking /
acceleration path.
Add a safe_clamp() helper (normalizes inverted bounds) and use it ONLY where
Lo<=Hi cannot be proven at compile time (config min/max pairs, sign-dependent
expressions, container underflow). Sites with constant bounds or [0, x>=0]
keep std::clamp. Remove the manual std::minmax workarounds and rewrite the
damaged-track jolt code value-first.
- The `TMoverParameters::derail()` function has been renamed to `::Derail()`, with a capital D.
- All derail events now use that function.
- Simplified and unified the logic behind different derail types.
- The `dtrack_freerail` track type is now slightly increasing the chance of derailing on a tight curve, as it was the intention.
- A new `DerailReason` enum has been created which holds all derail types.
- The `DerailReason` field in the `TMoverParameters` class has been removed.
- This was a transient field which is not necessary anymore.
- The logging functionality as such has been moved from `DynObj.cpp` to `Mover.cpp`.
