Assembly: RevitAPI (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0)
When a RevisionCloud is visible on a ViewSheet (either because it is directly placed on that ViewSheet or because it is visible in a View placed on the ViewSheet), any revision schedules displayed on the ViewSheet will automatically include the Revision associated with the RevisionCloud.
Note also that when a RevisionCloud is created in a ViewLegend, it is treated as a legend representation of what a RevisionCloud looks like rather than as an actual indication of a change to the model. As a result, RevisionClouds in ViewLegends will not affect the contents of revision schedules.
RevisionClouds are created from a collection of sketched curves. Each curve will have a series of "cloud bumps" drawn along it to form the appearance of a cloud. There is no requirement that the curves form closed loops.