Improved Car Automatic Transmission

A plugin for Euro Truck Simulator 2 that makes the automatic gearbox behave like a car's automatic instead of a truck's. Written for car mods, but it applies to every vehicle. The gearbox shifts one gear at a time and reads the throttle. Light pedal upshifts early and cruises at low revs, more pedal holds the gears longer and downshifts for acceleration before you reach the floor, and kickdown drops to the lowest gear the engine can pull.

This is my own work, released under the MIT license. The full source code is included in the download and available on GitHub: github.com/deppelover/car_automatic_transmission

Requirements

Developed and verified against Euro Truck Simulator 2, Windows 64-bit, Version 1.61.0.254. Tested with Pedals and Keyboard.

It locates the gearbox code by byte patterns instead of fixed addresses, so it normally survives game updates and if it cannot find what it expects, it does nothing at all.

Installation

This is not an .scs mod, so it does NOT go into your mod folder.

Copy the "bin" folder from the archive into your ETS2 installation directory, so the DLL ends up here:

Create the "plugins" folder if it does not exist. Start the game once and a car_automatic_transmission.cfg holding the defaults appears next to the DLL.

To uninstall, just delete the DLL.

Configuration

Edit car_automatic_transmission.cfg and restart the game. Every setting is optional and anything you leave out keeps its default. The values below are the defaults.

Gear Selection:
enabled = 1
   0 turns the plugin off completely.

up_step = 1
   Gears per upshift. 1 = sequential, 0 = unlimited.

down_step = 2
   Gears per downshift.

kick_step = 0
   Gears per kickdown. 0 = as far as needed.

downshift_on_accel = 1
   1 allows downshifting while accelerating, 0 is stock behaviour.

Shift-Map:
Moves the rpm window up with the throttle, so the gearbox downshifts earlier under load and holds gears longer.

min_rpm_hi = 0.65
   Main control. Minimum rpm at full pedal, as a fraction of the rev limit.

thr_lo = 0.45
   Below this pedal position, shift points stay stock.

thr_hi = 0.85
   At this pedal position the map is fully applied.

thr_curve = 1.6
   Above 1 makes the lower pedal range gentler.

thr_peak = 0.90
   Ceiling for the top of the window, as a fraction of the rev limit.

thr_gain = 3.00
   Safety ceiling on the shift. 0 disables the map.

Tuning: downshifts too eager? Lower min_rpm_hi or raise thr_lo. Too lazy? Raise min_rpm_hi or lower thr_hi. If it upshifts too early while cruising, lower thr_lo to about 0.15 and raise min_rpm_hi.

Shift timing:
upshift_delay = 0.80
   Lockout in seconds before the next upshift. 0 = off.

downshift_delay = 0.00
   The same for downshifts.

Debugging:
status_file = 0
   1 writes one status line to car_automatic_transmission.txt.

Multiplayer

Single player only. Do not use with TruckersMP or Convoy.

Note on Antivirus

The DLL patches the game's code in memory, which some scanners flag by behaviour alone. It is unsigned. The full source is included so you can read it and build the DLL yourself.

Please leave a comment if you run into any bugs or if something isn't working properly, and I will fix it.