diff options
| -rw-r--r-- | src/ground_vehicle.cpp | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/src/ground_vehicle.cpp b/src/ground_vehicle.cpp index cc2360d3f..1c706b5c6 100644 --- a/src/ground_vehicle.cpp +++ b/src/ground_vehicle.cpp @@ -151,8 +151,16 @@ int GroundVehicle<T, Type>::GetAcceleration() const } if (mode == AS_ACCEL) { - /* Divide by 4 to compensate for the wacky game scale. */ - return (force - resistance) / (mass * 4); + /* Easy way out when there is no acceleration. */ + if (force == resistance) return 0; + + /* When we accelerate, make sure we always keep doing that, even when + * the excess force is more than the mass. Otherwise a vehicle going + * down hill will never slow down enough, and a vehicle that came up + * a hill will never speed up enough to (eventually) get back to the + * same (maximum) speed. */ + int accel = (force - resistance) / (mass * 4); + return force < resistance ? min(-1, accel) : max(1, accel); } else { return min(-force - resistance, -10000) / mass; } |