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--  State............ : Follow
--  Author........... : 
--  Description...... : 
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function CarDemoCamera.Follow_onLoop ( )
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	local target = this.hTarget ( )
    
    if ( target ~= nil )
    then
        local dt            = application.getLastFrameTime ( )
        local o             = this.getObject ( )
        local tx, ty, tz    = object.getTranslation ( target, object.kGlobalSpace )
        local vx, vy, vz    
        local dist          = 7
        local focale        = 23
        local speed         = dynamics.getLinearSpeed ( target )
        local minspeed      = 5

        
        if ( this.bMoveBack ( ) )
        then
            vx, vy, vz    = object.getDirection   ( target, object.kGlobalSpace )
        else
            vx, vy, vz    = object.getTranslation ( o, object.kGlobalSpace )
            vx, vy, vz    = math.vectorSubtract   ( tx, ty, tz, vx, ty, vz )
            vx, vy, vz    = math.vectorNormalize  ( vx, vy, vz )
        end
        
        if ( speed > minspeed )
        then
            local factor    = math.min ( 35 - minspeed, speed - minspeed ) / ( 35 - minspeed )
            dist            = dist   - 0.5 * dist * factor
            focale          = focale +  40        * factor
        end                 

        dist            = dist   + vy * 5
        focale          = focale + vy * 5

        dist            = math.interpolate ( this.nCurDist   ( ), dist,   2 * dt )
        focale          = math.interpolate ( this.nCurFocale ( ), focale, 2 * dt )
        
        this.nCurDist   ( dist   )
        this.nCurFocale ( focale )        
        
        local lookUp        = vy > 0.95
        vx, vy, vz          = math.vectorNormalize  ( vx, 0, vz )
        vx, vy, vz          = math.vectorScale      ( vx, vy, vz, -dist )
        vx, vy, vz          = math.vectorAdd        ( vx, vy, vz, tx, ty + 3 * ( 30 - math.min ( 30, speed ) ) / 30, tz )
    
        -- LINEAR CONTROLLER
        ---[[
        local ox, oy, oz    = object.getTranslation ( o, object.kGlobalSpace )
        
        vx, vy, vz = math.vectorSubtract  ( vx, vy, vz, ox, oy, oz )
        local lmax = math.vectorLength    ( vx, vy, vz )

        vx, vy, vz = math.vectorNormalize ( vx, vy, vz )
        
        local scl  = math.clamp ( speed, 0.25, 12 )
        vx, vy, vz = math.vectorScale     ( vx, vy, vz, scl * 1.4 * dt )
        local l    = math.min (  math.vectorLength ( vx, vy, vz ), lmax )
        vx, vy, vz = math.vectorNormalize ( vx, vy, vz )
        vx, vy, vz = math.vectorScale     ( vx, vy, vz, l )
        

        object.translate        ( o, vx, vy, vz,        object.kGlobalSpace )
        object.lookAt           ( o, tx, ty + 0.5, tz,  object.kGlobalSpace, 1 )
        camera.setFieldOfView   ( o, focale )
        
        -- Motion blur
        --
        minspeed = 13
        local maxspeed = 30
        local factor   = 0.1 * math.clamp ( speed - minspeed, 0, maxspeed - minspeed ) / ( maxspeed - minspeed )
        factor = math.clamp ( factor / dt, 0, 0.8 )
        camera.setMotionBlurFactor ( o, factor )
    end
	
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end
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