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WheelAxle

WheelAxle​

Description

Handles the connection of two wheels on a vehicle, allowing for dynamic suspension adjustments based on axle load.

Functions

delete​

Description

Definition

delete()

Code

function WheelAxle:delete()
end

fillDebugValues​

Description

Definition

fillDebugValues()

Arguments

anydebugTable

Code

function WheelAxle:fillDebugValues(debugTable)
    local dynamicSuspension = self.dynamicSuspension
    local physics1, physics2 = self.wheel1.physics, self.wheel2.physics
    if dynamicSuspension ~ = nil then
        debugTable[ 1 ] = debugTable[ 1 ] .. string.format( "%d\n" , self.wheel1.wheelIndex)
        debugTable[ 2 ] = debugTable[ 2 ] .. string.format( "%d\n" , self.wheel2.wheelIndex)

        debugTable[ 3 ] = debugTable[ 3 ] .. string.format( "%2.2f\n" , physics1:getTireLoad() + physics2:getTireLoad())

        local maxLoad = dynamicSuspension.maxLoad or(physics1.restLoad * 2 + physics2.restLoad * 2 )
        debugTable[ 4 ] = debugTable[ 4 ] .. string.format( "%2.2f\n" , maxLoad)

        debugTable[ 5 ] = debugTable[ 5 ] .. string.format( "%.2f\n" , dynamicSuspension.appliedAlpha)

        local springMultiplier = MathUtil.lerp( 1 , dynamicSuspension.springLoadMultiplier, dynamicSuspension.appliedAlpha)
        local dampingMultiplier = MathUtil.lerp( 1 , dynamicSuspension.dampingLoadMultiplier, dynamicSuspension.appliedAlpha)
        debugTable[ 6 ] = debugTable[ 6 ] .. string.format( "x%.2f\n" , springMultiplier)
        debugTable[ 7 ] = debugTable[ 7 ] .. string.format( "x%.2f\n" , dampingMultiplier)

        if self.dynamicSuspension.componentJointIndex ~ = nil then
            debugTable[ 8 ] = debugTable[ 8 ] .. string.format( "%d\n" , self.dynamicSuspension.componentJointIndex)

            local componentSpringMultiplier = MathUtil.lerp( 1 , dynamicSuspension.componentSpringLoadMultiplier, dynamicSuspension.appliedAlpha)
            local componentDampingMultiplier = MathUtil.lerp( 1 , dynamicSuspension.componentDampingLoadMultiplier, dynamicSuspension.appliedAlpha)
            debugTable[ 9 ] = debugTable[ 9 ] .. string.format( "x%.2f\n" , componentSpringMultiplier)
            debugTable[ 10 ] = debugTable[ 10 ] .. string.format( "x%.2f\n" , componentDampingMultiplier)
        else
                debugTable[ 8 ] = debugTable[ 8 ] .. "n/a\n"
                debugTable[ 9 ] = debugTable[ 9 ] .. "n/a\n"
                debugTable[ 10 ] = debugTable[ 10 ] .. "n/a\n"
            end
        end
    end

getDebugValueHeader​

Description

Definition

getDebugValueHeader()

Code

function WheelAxle.getDebugValueHeader()
    return { "w1\n" , "w2\n" , "load\n" , "maxLoad\n" , "alpha\n" , "spring\n" , "damp\n" , "compJ\n" , "jSpring\n" , "jDamp\n" }
end

loadFromXML​

Description

Definition

loadFromXML()

Arguments

anyxmlFile
anykey

Code

function WheelAxle:loadFromXML(xmlFile, key)
    self.wheelNode1 = xmlFile:getValue(key .. "#wheel1" , nil , self.vehicle.components, self.vehicle.i3dMappings)
    self.wheelNode2 = xmlFile:getValue(key .. "#wheel2" , nil , self.vehicle.components, self.vehicle.i3dMappings)

    if self.wheelNode1 = = nil or self.wheelNode2 = = nil then
        Logging.xmlError(xmlFile, "WheelAxle '%s' missing wheel1 or wheel2" , key)
        return false
    end

    self.wheel1 = self.vehicle:getWheelByWheelNode( self.wheelNode1)
    self.wheel2 = self.vehicle:getWheelByWheelNode( self.wheelNode2)

    -- if wheels are not available in a certain configuration, we ignore the definition silently
        if self.wheel1 = = nil or self.wheel2 = = nil then
            return false
        end

        local springLoadMultiplier = xmlFile:getValue(key .. ".dynamicSuspension#springLoadMultiplier" , 1 )
        local dampingLoadMultiplier = xmlFile:getValue(key .. ".dynamicSuspension#dampingLoadMultiplier" , 1 )
        if springLoadMultiplier ~ = 1 or dampingLoadMultiplier ~ = 1 then
            self.dynamicSuspension = { }

            self.dynamicSuspension.springLoadMultiplier = springLoadMultiplier
            self.dynamicSuspension.dampingLoadMultiplier = dampingLoadMultiplier

            self.dynamicSuspension.maxLoad = xmlFile:getValue(key .. ".dynamicSuspension#maxLoad" )
            self.dynamicSuspension.interpolationTime = 1 / xmlFile:getValue(key .. ".dynamicSuspension#interpolationTime" , 1 )

            self.dynamicSuspension.interpolatedAlpha = 0
            self.dynamicSuspension.appliedAlpha = 0

            if self.vehicle.setDependentComponentJointBaseFactors ~ = nil then
                self.dynamicSuspension.componentJointIndex = xmlFile:getValue(key .. ".dynamicSuspension.componentJoint#index" , nil )
                if self.dynamicSuspension.componentJointIndex ~ = nil then
                    self.dynamicSuspension.componentSpringLoadMultiplier = xmlFile:getValue(key .. ".dynamicSuspension.componentJoint#springLoadMultiplier" , 1 )
                    self.dynamicSuspension.componentDampingLoadMultiplier = xmlFile:getValue(key .. ".dynamicSuspension.componentJoint#dampingLoadMultiplier" , 1 )
                end
            end
        end

        return true
    end

new​

Description

Definition

new()

Arguments

anyvehicle
anycustomMt

Code

function WheelAxle.new(vehicle, customMt)
    local self = setmetatable( { } , customMt or WheelAxle _mt)

    self.vehicle = vehicle

    return self
end

registerXMLPaths​

Description

Definition

registerXMLPaths()

Arguments

anyschema
anykey

Code

function WheelAxle.registerXMLPaths(schema, key)
    schema:register(XMLValueType.NODE_INDEX, key .. "#wheel1" , "First wheel of the axle" )
    schema:register(XMLValueType.NODE_INDEX, key .. "#wheel2" , "Second wheel of the axle" )

    schema:register(XMLValueType.FLOAT, key .. ".dynamicSuspension#springLoadMultiplier" , "Multiplier for spring value while maxLoad is applied on the wheels" , 1 )
        schema:register(XMLValueType.FLOAT, key .. ".dynamicSuspension#dampingLoadMultiplier" , "Multiplier for damping value while maxLoad is applied on the wheels" , 1 )

            schema:register(XMLValueType.FLOAT, key .. ".dynamicSuspension#maxLoad" , "Axle load as reference for springLoadMultiplier/dampingLoadMultiplier to adjust the physics behaviour in high load situations" , "restLoad of all wheels multiplied by 2" )
                schema:register(XMLValueType.TIME, key .. ".dynamicSuspension#interpolationTime" , "Interpolation time for tire load" , 1 )

                    schema:register(XMLValueType.INT, key .. ".dynamicSuspension.componentJoint#index" , "Index of the axle component joint" )
                    schema:register(XMLValueType.FLOAT, key .. ".dynamicSuspension.componentJoint#springLoadMultiplier" , "Multiplier for component joint spring value while maxLoad is applied on the wheels" , 1 )
                        schema:register(XMLValueType.FLOAT, key .. ".dynamicSuspension.componentJoint#dampingLoadMultiplier" , "Multiplier for component joint damping value while maxLoad is applied on the wheels" , 1 )
                        end

update​

Description

Definition

update()

Arguments

anydt

Code

function WheelAxle:update(dt)
    if self.dynamicSuspension ~ = nil then
        local dynamicSuspension = self.dynamicSuspension
        local physics1, physics2 = self.wheel1.physics, self.wheel2.physics

        local axleLoad = physics1:getTireLoad() + physics2:getTireLoad()
        if axleLoad ~ = 0 then -- zero while not added to physics yet
            local restLoad = physics1.restLoad + physics2.restLoad
            local maxLoad = self.maxLoad or(physics1.restLoad * 2 + physics2.restLoad * 2 )
            local targetAlpha = MathUtil.inverseLerp(restLoad, maxLoad, axleLoad)

            local direction = math.sign(targetAlpha - dynamicSuspension.interpolatedAlpha)
            dynamicSuspension.interpolatedAlpha = math.clamp(dynamicSuspension.interpolatedAlpha + direction * dt * dynamicSuspension.interpolationTime, 0 , 1 )

            if math.abs(dynamicSuspension.interpolatedAlpha - dynamicSuspension.appliedAlpha) > 0.05 then
                dynamicSuspension.appliedAlpha = dynamicSuspension.interpolatedAlpha

                local springMultiplier = MathUtil.lerp( 1 , dynamicSuspension.springLoadMultiplier, dynamicSuspension.appliedAlpha)
                local dampingMultiplier = MathUtil.lerp( 1 , dynamicSuspension.dampingLoadMultiplier, dynamicSuspension.appliedAlpha)

                physics1:setSuspensionMultipliers(springMultiplier, dampingMultiplier)
                physics2:setSuspensionMultipliers(springMultiplier, dampingMultiplier)

                if self.dynamicSuspension.componentJointIndex ~ = nil then
                    local componentSpringLoadMultiplier = MathUtil.lerp( 1 , dynamicSuspension.componentSpringLoadMultiplier, dynamicSuspension.appliedAlpha)
                    local componentDampingLoadMultiplier = MathUtil.lerp( 1 , dynamicSuspension.componentDampingLoadMultiplier, dynamicSuspension.appliedAlpha)

                    self.vehicle:setDependentComponentJointBaseFactors(dynamicSuspension.componentJointIndex, componentSpringLoadMultiplier, componentDampingLoadMultiplier, true )
                    self.vehicle:updateDependentComponentJointValues( false , true )
                end
            end
        end
    end
end