frame
Produces one immutable frame synchronously on the owner thread.
Pending content changes are reconciled before measurement, layout, paint, and semantics run in order on the retained tree. When content was not rebuilt and both constraints and the whole-tree revision are unchanged, implementations may return the same immutable frame instance without rerunning the pipeline. The returned frame owns detached read-only snapshots and does not retain the session or source collections. A pipeline failure poisons the session and performs cleanup before rethrowing the exact primary failure.
Return
an immutable frame snapshot from the successful owner-thread pass.
Parameters
the root measurement constraints for this frame.
Throws
when called from the wrong thread, reentrantly, or while the session is not attached.
when content, reconciliation, measurement, layout, paint, semantics, or cleanup fails; the first failure remains primary with later distinct failures suppressed.
Produces one immutable frame after delivering an explicit monotonic timestamp to time-aware nodes.
Equal timestamps are legal, and nodes invalidate output only when their discrete presentation changes.
Return
immutable frame snapshot, potentially the previous instance when no output changed.
Parameters
root measurement constraints.
timestamp from the owning platform clock.