PlatformDrawCommand
Immutable opaque draw payload shared only between a platform element and its matching runtime adapter.
Core retains the payload by reference and preserves its position in the ordered display list without inspecting it. Implementations must be immutable snapshots that are safe to retain after the originating paint callback returns. A backend that does not recognize an implementation must fail before producing partial output.
Functions
Optionally returns an immutable payload for fractional placement or scale. Source contains the original local bounds; destination preserves exact transformed edges. Core passes the result to the same backend inside enclosing integer bounds without interpreting it. Null preserves explicit rejection for backends that cannot transform their native presentation.