Gear Shifter

• Game
• Simulation
• Sounds
• Touch

SP4CEBAR 2022-12-19 19:26 (Edited)

Vrooom... dud dud dud...

　　　　　　　　Open In Editor

Guide to acceleration

1. Press the "s" button to start the car
2. Drag the gear shifter to the first gear
3. Drag the left "clutch" slider downward slowly to start accelerating (to disengage the clutch)
4. Drag the right-most slider upwards to throttle up (to engage the gas pedal)
5. Drag the clutch slider up (to engage it)
6. Switch to the next gear
7. Repeat from step 3

Things you can do

• accelerate in a car-like manner
• stall the engine
• use brakes
• rev
• go fast before switching to a low gear and make the engine scream
• try to hold specific speeds

Controls

• drag the pedals upward to engage them
  • the pedals from left to right are: clutch, brake, and throttle
  • clutch will be locked on when fully engaged
• drag the gear shifter in a gear-shifter-like manner to change gears
• tap the tachometer to switch the speedometer between KMpH and MpH
• press the button labeled "s" to start the car

known bugs

1. direction changes cause negative engine speed
2. tapping on the background just after starting lowers the rpm

Related

• Gear Racer - Drive through a desert with the same controls

Backstory

I'm just sketching out some code for in Unity.
It's a gear shifter that's designed to feel as natural as possible. I added a spring functionality so that you can shift from gear two (bottom left) to gear three (top middle) by dragging: up, wait, up, just like in a real car.

It would've taken me ages to design it in unity, designing it in NX first and implementing this in Unity should be easier.
NX is still my favorite programming language!

was8bit 2022-12-19 20:32

"NX is still my favorite programming language!"

Me2

SP4CEBAR 2025-03-09 21:08 (Edited)

Update:

• added gear ratio calculation and display
• added engine revolution speed calculation and display (the dial sprite)
• added car speed calculation and display

The calculations mentioned can be found in the "ENGINE" subroutine

The current calculations have a few flaws:

• higher gears make the engine weaker and therefore slower
• engaging the clutch results in near zero resistance and therefore a near infinite engine revolution speed
• the car speed keeps going up
• brakes are very powerful

SP4CEBAR 2025-03-09 21:24 (Edited)

Update 2

• resolved the near-zero resistance by adding a base-level resistance
• refactored arbitrary numbers like the base resistance and base throttle to variables

was8bit 2025-03-10 03:48

:)

SP4CEBAR 2025-03-10 07:25

Update 3

• the preferred engine speed is raised by the gear (which is slightly incorrect)
• the resistance now makes the revolution speed change slower

SP4CEBAR 2025-03-15 09:40 (Edited)

Update 4 - accurate custom speedometer

• more accurate speedometer and tachometer
• tap the displays to switch between KMpH and MpH

SP4CEBAR 2025-03-15 11:13 (Edited)

Update 5 & 6 - starting button

• added a car-starting button
• tried to make the engine stall when it is running too slowly

SP4CEBAR 2025-03-15 20:58 (Edited)

update 7 - clutch lock

• The clutch will now be locked on when engaged all the way so that you can shift while the clutch is engaged and you can rev.
• Tweaked the engine behavior a little bit to make a lower car speed increase the engine resistance (so that the engine runs slower when the car is too slow for the gear)

SP4CEBAR 2025-03-15 21:07 (Edited)

Update 8 - speed linked to engine

• I think I managed to get it to feel sort of realistic: the engine now stalls naturally when the clutch or released immediately during shifting
• the engine speed should now be affected by the car speed as well as the other way around making the two linked (unless the clutch is engaged or the gear is free)

SP4CEBAR 2025-03-15 21:16 (Edited)

Update 9 - speed preservation

• Speed is now preserved while the clutch is engaged allowing you to change gears to keep accelerating, this also allows you to go really fast before switching to a low gear and having the engine go crazy (just like in real cars)
• Brake works again

SP4CEBAR 2025-03-15 21:41

Update 10 - Cleanup

• the speed is no longer reset when the gear is free
• arbitrary values have been collected into parameters in the GET_ENGINE_PARAM subroutine
• useless comments have been moved to the trashbin area

SP4CEBAR 2025-03-15 21:52 (Edited)

Update 11 - Tweaking

• tweaked the engine so the top speed is about 170 KM/H
• reorganized the engine parameter code and made some parameters dependent on the values of others to be able to change them more dynamically

SP4CEBAR 2025-03-15 21:57 (Edited)

Update 12 - made it harder

• tweaked the engine to make it slightly more likely to stall

SP4CEBAR 2025-03-15 22:54

Update 13 - Code cleanup

• restructured the code to make it easier to read
• binned some useless comments
• added "EXIT_SUB" to unused subprograms

SP4CEBAR 2025-03-15 22:56 (Edited)

For those interested,

• the GET_ENGINE subroutine handles most of the engine logic
• and the GET_ENGINE_PARAM subroutine has all the parameters

SP4CEBAR 2025-03-15 23:02 (Edited)

Update 14 - Quick fix

• fixed a crash introduced in the previous version

was8bit 2025-03-16 03:42

Wowzers!

SP4CEBAR 2025-03-17 07:24 (Edited)

Update 15 - more tweaking

• tweaked the base-throttle level to achieve realistic speeds in different gears if no gas was applied
• made it even easier to stall the car
• added a CLUTCH_WEAR_DIST parameter so that the first 20% of the clutch pedal does absolutely nothing

was8bit 2025-03-17 14:54

Have u seen this game?

https://www.youtube.com/watch?v=nNGCb9Dh4HA

SP4CEBAR 2025-03-17 16:18

Update 16

• refactored the GET_ENGINE subroutine
• made the clutch pedal less sensitive (and more precise to use)

SP4CEBAR 2025-03-17 16:26

Interesting game! it does appear to be simpler than this here

was8bit 2025-03-17 16:51

The dynamics have always eluded me.... with your knowledge of gears, you could make a version similar to it... the interface would be different, it would probably be easier to start a new game with the new interface, then add gearing dynamics to it...

I tried a long time ago to make this game, but i was clueless about the gear dynamics, so it didnt play well at all ...

SP4CEBAR 2025-03-17 17:30

Update 17

• redesigned the user interface
• something I can't remember anymore

SP4CEBAR 2025-03-17 17:31

Feel free to remix it, the code has been organized and refactored, I think you can navigate through it to find the bits you need

SP4CEBAR 2025-03-17 17:48

Update 18

• slight refactoring and organizing
• moved the audio call to the SOUNDS subroutine
• removed a duplicate call to the car visuals

SP4CEBAR 2025-03-17 20:13 (Edited)

Update 19

• Emptied the code trashbin
• Renamed Engine_angular_speed to just engine_speed
• renamed the different engine subroutines to match their output variable name (seems like a good convention for me to keep from now on)
• the starting button will now deactivate itself in the GUI when released (change is not noticeable)
• the starting button has been moved upwards
• probably some more refactoring

SP4CEBAR 2025-03-17 20:34

Update 20

• turned the CAR subroutine into a subprogram so that all the subroutines called inside it have their variables effectively isolated

SP4CEBAR 2025-03-17 21:13

Update 21

• engine start sound
• goal of 170 KMPH
• progression percentage
• refactoring of the display's code

SP4CEBAR 2025-03-17 21:19

Update 22

• added labels to the pedals

was8bit 2025-03-17 21:45

TY :)

SP4CEBAR 2025-03-18 08:10 (Edited)

Update 23

• limited the RPM display so it can't move beyond 8.75 *1000 RPM

SP4CEBAR 2025-03-18 08:41

Update 24

• added a rev limiter
• reduced the goal to 150 KMPH
• refactored unit conversions to global variables

SP4CEBAR 2025-03-18 08:46 (Edited)

I would like your opinion on this: does the sound you hear match the RPM you read on the Tachometer?

Also, should some meters progress slower or faster than they do now?

SP4CEBAR 2026-10-10 19:20

update 25

• car mass
• rpm-based power
• exponential-ish gear ratios
• tweaking the parameters

SP4CEBAR 2026-10-10 19:22 (Edited)

It's fun to tweak the parameters, you can also look them up in the code and tweak their formulas

GET_ENGINE_PARAM:
  GEAR_RATIO_FACTOR    = 0.05

  BASE_RESISTANCE      = 0.6
  BASE_CAR_RESISTANCE  = 5

  'kg
  AXLE_MASS= 10
  'kg
  CAR_MASS = 1500

  BASE_THROTTLE        = 1.7
  MAX_THROTTLE         = 9

  ENGINE_BASE_POWER    = 5
  ENGINE_RPM_BOOST     = 0.5
  ENGINE_REVVING_SPEED = 0.5

  MAX_ENGINE_SPEED     = 8.75 *G_KRPM_TO_RPS
  SAFE_ENGINE_SPEED    = 8.4 *G_KRPM_TO_RPS

  STARTING_MAX_SPEED   = 50
  STARTING_POWER       = 0.1

  STALLING_MIN_SPEED   = 5
  STALLING_POWER       = 0.04

  CLUTCH_WEAR_DIST     = 0.2
  BRAKE_POWER          = 0.02
RETURN

'=+=+=+=+= D A T A =+=+=+=+=

GEAR_RATIOS:
DATA 0, 1, 2, 4, 8, 12, -1

SP4CEBAR 2026-10-10 20:27 (Edited)

update 26

• tweaks

SP4CEBAR 2026-10-10 20:29

update 27

• gamification: hold the given speed for five seconds for the new target speed to appear