Moving Level Elements, Rails and OneTimeRot

Whether you want levels to have moving platforms or for path/hazards to open up upon certain conditions, you will need to use Rails or OneTimeRot parameters.

Note that if you want objects to stay how they were upon reset, leave Switchable–RespawnReset as 0, otherwise set it to 2.

Rails are listed in a separate structure as objects in a given level's byaml file. They come in different types, mainly differentiated by colour, although this writer does not understand the different between them.

    - Id: rail2
      IsClosed: false
      IsLadder: false
      IsLinkDest: false
      LayerConfigName: Cmn
      Links: {}
      ModelName: null
      Priority: !l 100
      RailPoints:
        - CheckPointIndex: !l 0
          ControlPoints:
            - {X: 280.00000, Y: -25.00000, Z: 610.00000}
            - {X: 280.00000, Y: -25.00000, Z: 610.00000}
          Id: rail2/0
          LayerConfigName: Cmn
          Links: {}
          OffsetX: 0.00000
          OffsetY: 0.00000
          OffsetZ: 0.00000
          Rotate: {X: 0.00000, Y: 0.00000, Z: 0.00000}
          Scale: {X: 1.00000, Y: 1.00000, Z: 1.00000}
          Translate: {X: 280.00000, Y: -25.00000, Z: 490.00000}
          UnitConfigName: RailPoint
          UseOffset: false
        - CheckPointIndex: !l 0
          ControlPoints:
            - {X: 280.00000, Y: -25.00000, Z: 610.00000}
            - {X: 280.00000, Y: -25.00000, Z: 610.00000}
          Id: rail2/1
          LayerConfigName: Cmn
          Links: {}
          OffsetX: 0.00000
          OffsetY: 0.00000
          OffsetZ: 0.00000
          Rotate: {X: 0.00000, Y: 0.00000, Z: 0.00000}
          Scale: {X: 1.00000, Y: 1.00000, Z: 1.00000}
          Translate: {X: 280.00000, Y: -25.00000, Z: 610.00000}
          UnitConfigName: RailPoint
          UseOffset: false
      RailType: Bezier
      Rotate: {X: 0.00000, Y: 0.00000, Z: 0.00000}
      Scale: {X: 1.00000, Y: 1.00000, Z: 1.00000}
      Translate: {X: 0.00000, Y: 0.00000, Z: 0.00000}
      UnitConfigName: Rail

The location of the rail itself does not matter, only that of the given RailPoints. You can use rails to rotate and even resize an object as well as dictate its path.

RailType can either be set to Linear or Bezier. If a rail is linear, you do not need ControlPoints, and as a result are restricted to straight lines. Bezier curves use ControlPoints to control what a RailPoint's given curve looks like.

Objects are attached to rails using the RailableParams–Rail link. In the byaml it looks like this:

Links:
        RailableParams__Rail:        
          - {DefinitionName: RailableParams__Rail, DestUnitId: rail3/0, UnitFileName: ''}

RailableParams__AttCalc: !l 0
RailableParams__BreakFrame: !l 30
RailableParams__ConstantVelUnitLength: 2.50000
RailableParams__Interpolation: !l 1
RailableParams__MoveFrame: !l 60
RailableParams__Patrol: !l 2
RailableParams__StandbyFrame: !l 0
RailableParams__Vel: !l 0

• ConstantVelUnitLength and MoveFrame describe the speed at which the object moves along the rail, with Vel performing some yet unknown role.
• Patrol describes how many times and in what way the objects moves along the rail. 0 means it only moves once, 1 means it will start its cycle again, 2 means it will move back the way it came until it finds its start point.