DEF TIME TimeSensor { loop TRUE cycleInterval 5 } #<l++>
  
    DEF COLORS ColorInterpolator {
          key [ 0 0.5 1 ]
          keyValue [ 1 0 0,  0 0 1, 1 0 0 ]
          } #<l++>
  
  ROUTE TIME.fraction_changed TO COLORS.set_fraction
  ROUTE COLORS.value_changed TO MATERIAL.diffuseColor