Struct Guest 

pub struct Guest<'a> { /* private fields */ }

Producer side: the guest engine writing opcodes and arena data into shared linear memory. Owns the header, ring, and arena regions as disjoint slices.

Implementations

impl<'a> Guest<'a>

pub fn new(mem: &'a mut [u8], layout: &MemoryLayout) -> Self

Create a guest view over the linear memory. init_memory MUST have been called on the same memory beforehand.

pub fn begin_frame(&mut self)

Record the start of a new frame.

pub fn pending(&self) -> usize

Number of opcodes written since the last begin_frame.

pub fn end_frame(&mut self)

End the frame: increments frameCount.

pub fn frame_count(&self) -> u32

Total frames produced so far.

pub fn create_node( &mut self, node_id: u32, component_type: u16, ) -> Result<(), RingError>

pub fn delete_node(&mut self, node_id: u32) -> Result<(), RingError>

pub fn insert_child( &mut self, parent: u32, child: u32, index: u32, ) -> Result<(), RingError>

pub fn remove_child(&mut self, parent: u32, child: u32) -> Result<(), RingError>

pub fn move_child( &mut self, parent: u32, child: u32, new_index: u32, ) -> Result<(), RingError>

pub fn push_opcode(&mut self, op: Opcode) -> Result<(), RingError>

Push a caller-built raw opcode into the ring. This is the escape hatch for foreign hosts (C ABI / FFM) that construct the 16-byte opcode themselves and write it into the shared ring in place.

pub fn set_property( &mut self, node_id: u32, property_id: u16, value_type: u8, value: u32, ) -> Result<(), RingError>

pub fn set_text(&mut self, node_id: u32, text: &str) -> Result<u32, RingError>

Set a node’s text content via the arena.

pub fn set_date( &mut self, node_id: u32, days: i32, millis: u32, ) -> Result<(), RingError>

Set a node’s date value via PARAMETER::SET_DATE (draft): days since the epoch (I32, pre-1970 negative) and millis of day (U32, 0..86,400,000).

pub fn set_design_token( &mut self, path: &str, value_type: u8, value: u32, ) -> Result<u32, RingError>

Override a design token globally via PARAMETER::SET_DESIGN_TOKEN: path (arena string) → value of value_type. Applies everywhere the renderer resolves tokens (spec/TOKENS.md). A dark.-prefixed path overrides the dark variant. Returns the arena offset of the path.

pub fn set_design_token_string( &mut self, path: &str, value: &str, ) -> Result<u32, RingError>

Override a design token with a STRING value via PARAMETER::SET_DESIGN_TOKEN (spec/TOKENS.md): both the token path and the value are arena strings — A = path ref, B = STRING value type, C = value ref. Returns the arena offset of the path.

pub fn alloc(&mut self, bytes: &[u8]) -> Result<u32, ArenaError>

Allocate arbitrary bytes into the arena, returning the offset.

pub fn alloc_str(&mut self, s: &str) -> Result<u32, ArenaError>

Allocate a string into the arena, returning the offset.

pub fn reset(&mut self) -> Result<(), RingError>

pub fn drain_events(&mut self) -> Vec<Event>

Drain all pending raw-input events written by the host into the event ring, decoding each 16-byte EVENT opcode into a typed Event.

The guest (app/engine) polls this to receive renderer-reported inputs.

pub fn drain_event_opcodes(&mut self) -> Vec<Opcode>

Drain raw EVENT-category opcodes from the host → guest event ring as their 16-byte wire form (no decoding). Used by foreign hosts that want the raw bytes.

pub fn drain_event_opcodes_max(&mut self, max: usize) -> Vec<Opcode>

Drain at most max raw EVENT-category opcodes, leaving the rest pending for a later call (so a caller with a fixed-size buffer never drops events it couldn’t copy).

pub fn event_arena_cursor(&self) -> u32

The host → guest event arena bump cursor (diagnostics/tests).

pub fn push_event_opcode(&mut self, op: Opcode) -> Result<(), RingError>

Push a raw EVENT-category opcode into the host → guest event ring.

This is the host-side write (the renderer reporting an input). Exposed here (guest can hold the ring too) so a C-ABI shim can inject raw event opcodes without round-tripping through the typed Event enum.