anchor.diff:              | None -> world
   
           static member internal propagateEntityAffineMatrix3 mount mounter world =
  -            let mounterState = World.getEntityState mounter world
  -            let rotationWorld = World.getEntityZotation mount world
  +            let mountState = World.getEntityState mount world
  +            let rotationWorld = mountState.Zotation
  +            let scaleWorld = mountState.Scale
               let affineMatrixWorld = World.getEntityAffineMatrix mount world
               let affineMatrixLocal = World.getEntityAffineMatrixLocal mounter world
               let affineMatrix = affineMatrixWorld * affineMatrixLocal
  +            let mounterState = World.getEntityState mounter world
               let position = Vector3.Transform (mounterState.PositionLocal, affineMatrix)
  -            let rotation = mounterState.ZotationLocal * rotationWorld // mul local before world
  -            let scale = Vector3.Transform (mounterState.ScaleLocal, affineMatrix)
  +            let rotation = mounterState.ZotationLocal * rotationWorld
  +            let scale = mounterState.ScaleLocal * scaleWorld
               let mutable transform = mounterState.Transform
               transform.Position <- position
               transform.Zotation <- rotation
  
positive.code:                     let world = if entityState.Mounted then World.propagateEntityAffineMatrix entity world else world
                      struct (true, world)
  
                  else // do position updates and propagation out-of-place.
  
                      // update PositionLocal property
                      let struct (_, world) =
                          World.updateEntityState (fun entityState ->
                              if value <> entityState.PositionLocal then
                                  let entityState = if entityState.Imperative then entityState else EntityState.diverge entityState
                                  entityState.PositionLocal <- value
                                  entityState
                              else Unchecked.defaultof<_>)
                              Property? PositionLocal value entity world
  
                      // compute mount position
                      let positionMount =
                          match Option.bind (tryResolve entity) (World.getEntityMountOpt entity world) with
                          | Some mount when World.getEntityExists mount world -> World.getEntityPosition mount world
                          | _ -> v3Zero
  
                      // update Position property
                      let world = World.setEntityPosition (positionMount + value) entity world |> snd'
                      struct (true, world)
  
              // nothing changed
  
negative.code:             let entityState = World.getEntityState entity world
              if v3Neq value entityState.Transform.Position then
                  if entityState.Optimized then
                      entityState.Position <- value
                      let world = if entityState.Mounted then World.propagateEntityAffineMatrix entity world else world
                      struct (true, world)
                  else
  