EBlackboardSizingPolicy

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RollbackBlackboard: this is a generic map that stores any type of data for local-only access. It will not be replicated. It can be used as a way for decoupled systems to store calculations or transient state data that isn't necessary to reconstitute the movement simulation from scratch. Examples: the normal of the current walkable floor, or time of the last movement mode change

Key Features:

• Rollback support: when movement simulations roll back during a correction, this blackboard also rolls back to previous values.
• Concurrent access: for async simulations, it provides concurrent access support so external systems / scripting can access data while new data is being authored
• Policies: there are a variety of policy options to control buffer sizing, invalidation behavior, and entry persistence.

Notes:

• This is implemented under-the-hood using circular buffers, alleviating the need for mem alloc/frees during use. It's important to create entries with policy settings appropriate for their use pattern.
• We use an "InternalWrapper" class to allow in-simulation objects like movement modes to use the same API, without needing to choose between internal- or external-facing functions.
• The "InternalWrapper" class will be replaced by a different pattern to govern access levels TODO:

Implement stronger concurrency controls at time of frame changes, and when new in-sim entries are written

• Implement sizing policies that rely on knowing a max number of elements to buffer (the backend may know these details)
• Consider using TArrays instead of circular buffers, due to the power-of-2 trick potentially wasting a lot of memory
• Expose for Blueprint use Determines how a blackboard's entry buffer is sized

Syntax

enum EBlackboardSizingPolicy  
{  
    FixedDeclaredSize,  
    FixedBackendBufferSize,  
    SingleEntry,  
}  
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enum EBlackboardSizingPolicy {     FixedDeclaredSize,     FixedBackendBufferSize,     SingleEntry, }

Values