Posted: 14 Dec 2010, 11:23
For those that are not frequenting the RVZT or who are new in the scene: I have recently had a hand in converting the cars of Carmageddon 1, Splat Pack and 2 to Re-Volt. Specifically I made the parameters part of the vehicles.
In the course of this, I found that the parameters.txt files of Re-Volt are eerily similar to the “carname”.txt files of Carmageddon 2 ((co-?)incidentally released one year before Re-Volt). Just look at this comparison of values from untwatted eagle3.txt in Carmageddon 2 and corresponding values in Re-Volt parameters.txt (the lines with • are from Carma, •• are from Re-Volt):
Carma2 eagle3.txt:
• START OF MECHANICS STUFF
•0.500000 // Minimum turning circle.
•• 0.5 RV wheel steeringratio (scale x1, but implemented differently and the other way around)
•200.0000 // Speed at red line in highest gear.
•• 50 RV TopSpeed (scale e.g. x0.25)
•5.000000 // Acceleration in highest gear (m/s^2) i.e. engine strength.
•• 5.0 RV EngineRate (scale x1, but modified with EngineRatio to give RC-type high acceleration; Carma-type acceleration is retained at scale x0.01 and then the necessary EngineRatio can be calculated as body_weight*wheel_radius*constant_coefficient and depends somewhat on various frictions)
•0.000000,0.070000,0.000000 // Centre of mass
•• 0.0, 0.07, 0.0 RV CoM (scale unknown)
•1.5 // Mass
•• 1.5 RV mass (scale e.g. 1t–>1kg)
•0.320000,0.270000,0.800000 // Angular momentum proportions
•• 3200, 8000, 2700 RV inertias (x, z, y–>x, y, z, scale x10,000; this example gives lifelike handling, it’s generally reduced to get the RC type handling of stocks; directly usable only at weight 1 (kg), for other weights a complex calculation is needed in RV)
•50.000000 // Downforce-to-weight balance speed
•• 2.0 RV DownForceMod (scale unknown, implementation unknown)
•// Wheels entry #1
•Left front // Identifier
•1 // Steerable flags
•• TRUE RV IsTurnable
•0 // Driven flags
•• FALSE RV IsPowered
•0.010000 // Suspension give
•• 100 RV stiffness front (scale x10,000, but not directly usable, as in RV suitable stiffness depends on weight)
•1.000000 // Damping factor
•• 10 RV damping front (scale x10, but not directly usable, as in RV suitable damping seems to depend on other things)
•1.000000 // Fractional reduction in friction when slipping
•• 1.0 RV kinetic friction (scale x1, but implemented the other way around)
•80.000000,80.500000 // Friction angles
•• Is this RV ToeIn that is totally undocumented and doesn’t seem to affect anything?
•2.000000 // Traction fractional multiplier
•• 0.02 RV grip (scale x0.01)
•0.050000 // Rolling resistance
•• 0.05, 0.05 RV axle friction (scale x1)
•// Wheels entry #2
•Right front // Identifier
•[...]
•// Wheels entry #3
•Left rear // Identifier
•[...]
•// Wheels entry #4
•Right rear // Identifier
•[...]
On a somewhat unrelated angle – for Carma 2, Stainless really used much the same physics engine as Carma 1, only made it more detailed (again, the lines with • are from Carma, •• are from Re-Volt).
Carma1 eagle.txt:
•START OF MECHANICS STUFF
•0, 0.08, 0.1 // centre of mass position
•• 0.0, 0.08, 0.1 RV CoM (scale unknown)
•0.5 // min turning circle radius
•• 0.5 RV wheel steeringratio (scale x1, but implemented differently and the other way around)
•0.01, 0.01 // suspension give (forward, back)
•• 100, 100 RV stiffness front, rear (scale x10,000, but not directly usable, as in RV suitable stiffness depends on weight)
•1 // damping factor
•• 10 RV damping (scale x10, but not directly usable, as in RV suitable damping seems to depend on other things)
•1 // mass in tonnes
•• 1 RV mass (scale e.g. 1t–>1kg)
•1 // fractional reduction in friction when slipping
•• 1.0 RV kinetic friction (scale x1, but implemented the other way around)
•0.3, 0.15, 0.9 // width, height, length(0.816, 1.216) for angular momentum calculation
•• 3000, 9000, 1500 RV inertias (x, z, y–>x, y, z, scale x10,000, but directly usable only at weight 1 (kg), for other weights a complex calculation is needed in RV)
•50 // speed at which down force = weight v. 2
•• 2.0 RV DownForceMod (scale unknown, implementation unknown)
•2.0 // traction fractional multiplier v. 2
•• 0.02 RV grip (scale x0.01)
•0.05, 0.05 // rolling resistance front and back v. 1
•• 0.05, 0.05 RV axle friction (scale x1)
•200 // speed at red line in highest gear v.1
•• 50 RV TopSpeed (scale e.g. x0.25)
•4 // acceleration in highest gear m/s^2 (i.e. engine strength) v.1
•• 4.0 RV EngineRate (scale x1, but modified with EngineRatio to give RC-type high acceleration; Carma-type acceleration is retained at scale x0.01 and then the necessary EngineRatio can be calculated as body_weight*wheel_radius*constant_coefficient and depends somewhat on various frictions)
No wonder it was possible to get the converted Carma cars behave so Carma-like in Re-Volt (see the Carmageddon Packs at RVZT)...
-----
CW
In the course of this, I found that the parameters.txt files of Re-Volt are eerily similar to the “carname”.txt files of Carmageddon 2 ((co-?)incidentally released one year before Re-Volt). Just look at this comparison of values from untwatted eagle3.txt in Carmageddon 2 and corresponding values in Re-Volt parameters.txt (the lines with • are from Carma, •• are from Re-Volt):
Carma2 eagle3.txt:
• START OF MECHANICS STUFF
•0.500000 // Minimum turning circle.
•• 0.5 RV wheel steeringratio (scale x1, but implemented differently and the other way around)
•200.0000 // Speed at red line in highest gear.
•• 50 RV TopSpeed (scale e.g. x0.25)
•5.000000 // Acceleration in highest gear (m/s^2) i.e. engine strength.
•• 5.0 RV EngineRate (scale x1, but modified with EngineRatio to give RC-type high acceleration; Carma-type acceleration is retained at scale x0.01 and then the necessary EngineRatio can be calculated as body_weight*wheel_radius*constant_coefficient and depends somewhat on various frictions)
•0.000000,0.070000,0.000000 // Centre of mass
•• 0.0, 0.07, 0.0 RV CoM (scale unknown)
•1.5 // Mass
•• 1.5 RV mass (scale e.g. 1t–>1kg)
•0.320000,0.270000,0.800000 // Angular momentum proportions
•• 3200, 8000, 2700 RV inertias (x, z, y–>x, y, z, scale x10,000; this example gives lifelike handling, it’s generally reduced to get the RC type handling of stocks; directly usable only at weight 1 (kg), for other weights a complex calculation is needed in RV)
•50.000000 // Downforce-to-weight balance speed
•• 2.0 RV DownForceMod (scale unknown, implementation unknown)
•// Wheels entry #1
•Left front // Identifier
•1 // Steerable flags
•• TRUE RV IsTurnable
•0 // Driven flags
•• FALSE RV IsPowered
•0.010000 // Suspension give
•• 100 RV stiffness front (scale x10,000, but not directly usable, as in RV suitable stiffness depends on weight)
•1.000000 // Damping factor
•• 10 RV damping front (scale x10, but not directly usable, as in RV suitable damping seems to depend on other things)
•1.000000 // Fractional reduction in friction when slipping
•• 1.0 RV kinetic friction (scale x1, but implemented the other way around)
•80.000000,80.500000 // Friction angles
•• Is this RV ToeIn that is totally undocumented and doesn’t seem to affect anything?
•2.000000 // Traction fractional multiplier
•• 0.02 RV grip (scale x0.01)
•0.050000 // Rolling resistance
•• 0.05, 0.05 RV axle friction (scale x1)
•// Wheels entry #2
•Right front // Identifier
•[...]
•// Wheels entry #3
•Left rear // Identifier
•[...]
•// Wheels entry #4
•Right rear // Identifier
•[...]
On a somewhat unrelated angle – for Carma 2, Stainless really used much the same physics engine as Carma 1, only made it more detailed (again, the lines with • are from Carma, •• are from Re-Volt).
Carma1 eagle.txt:
•START OF MECHANICS STUFF
•0, 0.08, 0.1 // centre of mass position
•• 0.0, 0.08, 0.1 RV CoM (scale unknown)
•0.5 // min turning circle radius
•• 0.5 RV wheel steeringratio (scale x1, but implemented differently and the other way around)
•0.01, 0.01 // suspension give (forward, back)
•• 100, 100 RV stiffness front, rear (scale x10,000, but not directly usable, as in RV suitable stiffness depends on weight)
•1 // damping factor
•• 10 RV damping (scale x10, but not directly usable, as in RV suitable damping seems to depend on other things)
•1 // mass in tonnes
•• 1 RV mass (scale e.g. 1t–>1kg)
•1 // fractional reduction in friction when slipping
•• 1.0 RV kinetic friction (scale x1, but implemented the other way around)
•0.3, 0.15, 0.9 // width, height, length(0.816, 1.216) for angular momentum calculation
•• 3000, 9000, 1500 RV inertias (x, z, y–>x, y, z, scale x10,000, but directly usable only at weight 1 (kg), for other weights a complex calculation is needed in RV)
•50 // speed at which down force = weight v. 2
•• 2.0 RV DownForceMod (scale unknown, implementation unknown)
•2.0 // traction fractional multiplier v. 2
•• 0.02 RV grip (scale x0.01)
•0.05, 0.05 // rolling resistance front and back v. 1
•• 0.05, 0.05 RV axle friction (scale x1)
•200 // speed at red line in highest gear v.1
•• 50 RV TopSpeed (scale e.g. x0.25)
•4 // acceleration in highest gear m/s^2 (i.e. engine strength) v.1
•• 4.0 RV EngineRate (scale x1, but modified with EngineRatio to give RC-type high acceleration; Carma-type acceleration is retained at scale x0.01 and then the necessary EngineRatio can be calculated as body_weight*wheel_radius*constant_coefficient and depends somewhat on various frictions)
No wonder it was possible to get the converted Carma cars behave so Carma-like in Re-Volt (see the Carmageddon Packs at RVZT)...
-----
CW