Physics Tutorial (GTA2)

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The physics of GTA2 vehicles, like top speed, weight, resilience and manoeuvrability, are stored in the nyc.gci file in the GTA2\data folder. This tutorial explains how these physics can be altered. You may want to use a physics editor or a tool like the GTA2 PowerManager to do this, although it's also posiible to alter physics manually.

Make sure you've made a back-up of nyc.gci before you start changing the file. There is a high risk of creating uncontrollable cars, so you'll probably need to be able to restore the file without having to reinstalling the game. Also, note that you can't play multiplayer with someone who has a different nyc.gci file.

Most editors use easy scrollbars to alter physics. If you want to do it manually, you need to open nyc.gci with Notepad. You'll see a list of all cars with their physics. The first car, the Romero, looks like this:

{Romero}
0 {model}
0 {turbo}
50 {value}
0 {pad}
f16.500 {mass}
f1.000 {front drive bias}
f0.500 {front mass bias}
f1.750 {brake friction}
f0.145 {turn in}
f0.450 {turn ratio}
f1.250 {rear end stability}
f0.180 {handbrake slide value}
f0.152 {thrust}
f0.245 {max_speed}
f1.000 {anti strength}
f0.065 {skid threshhold}
f0.550 {gear1 multiplier}
f0.680 {gear2 multiplier}
f1.000 {gear3 multiplier}
f0.107 {gear2 speed}
f0.165 {gear3 speed} 

Every line is a physic (explained between { and } ) with it's value. This values can be changed, but don't remove the 'f' and insert values with three digits behind the decimal separator (0.000), except 'value' and 'turbo'.

The table below lists all values with explanation and their minimum and maximum value. Do not exceed this minimum or maximum!

Physic Explanation Minimum Maximum
{Name} Name of the vehicle
{model} ID
{turbo} Extra thrust (see 'thrust') No turbo 0 1 Turbo
{value} value Cheap 0 999999 Expensive
{pad} Unknown 0 0
{mass} Weight Light 1.000 35.824 Heavy
{front drive bias} Steering Middle 0.000 1.000 Front
{front mass bias} Front weight Light 0.000 1.000 heavy
{brake friction} Changing forwards/backwards Slow 0.000 4.000 Fast
{turn in} Reaction speed Slow 0.000 1.000 Fast
{turn ratio} Corners Wide 0.001 1.000 Sharp
{rear end stability} Stability Unstable 0.000 4.000 Stable
{handbrake slide value} Handbrake Weak 0.000 1.000 Powerful
{thrust} Force Weak 0.000 1.000 Powerful
{max_speed} Top speed Slow 0.000 1.000 Fast
{anti strength} Vulnerability Invulnerable 0.000 10.000 Vulnerable
{skid threshhold} Skid marks Often 0.000 1.000 Few
{gear1 multiplier} Top speed backwards Slow 0.000 1.000 Fast
{gear2 multiplier} Extra speed 2nd gear Slow 0.000 1.000 Fast
{gear3 multiplier} Speed 3rd gear Slow 0.000 1.000 Fast
{gear2 speed} Speed backwards 2nd gear Traag 0.000 0.600 Snel
{gear3 speed} Speed 2nd gear Traag 0.000 0.600 Snel
Modding tutorials of Grand Theft Auto 2
Mapping Map Editor · Buildings · Roads · Water & animations · Slopes · Flat tiles · Collision info · Level edge · Zones · Putting a level ingame
Scripting Declarering: Main script · Script Compiler · Code lists · Commands · Vehicles · Objects · Sounds · Characters
Programming: IF · WHILE · COUNTERs · Subroutines · THREAD TRIGGERs · Kill Frenzies
Both Manual · Lighting · Car shops · Cranes & crushers · Gangs · Subway · Multiplayer levels
File types .gci · .gmp · .gxt · .mis · .mmp · .scr · .seq · .tmp · .sty
Other Texting · Physics · Creating vehicles · Terminology · Installing levels