Struct FrameInput 

#[non_exhaustive]
pub struct FrameInput {
    pub p1: Buttons,
    pub p2: Buttons,
    pub p3: Buttons,
    pub p4: Buttons,
    pub expansion: u8,
}

Per-frame controller input: four controller ports plus an expansion byte.

Each port is a Buttons value. Bit layout matches FCEUX .fm2 (bit0=A .. bit7=Right), which is exactly Buttons::bits.

Players 3 and 4 (v2.9.8)

p3 / p4 are the Four Score’s players, polled through $4016 / $4017 only while the adapter is plugged in (which the movie’s HardwareOptions::four_score records). Until v2.9.8 the struct held two ports, so a four-player recording captured half of what drove it and the .fm2 importer dropped pads 3 and 4.

Why #[non_exhaustive]

Adding p3 / p4 broke every caller that built the struct by literal, which is why the change waited for a breaking release. The next field is foreseeable – an expansion-port device byte, a soft-reset command – and .rnm already stores its per-frame width so the FORMAT side of such a field is additive; #[non_exhaustive] makes the API side additive too. Outside this crate a frame is built with Self::new, Self::four_players or Default and then edited through its public fields, all of which keep compiling when a field is added.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

p1: Buttons

Player 1 ($4016) button state.

p2: Buttons

Player 2 ($4017) button state.

p3: Buttons

Player 3 (Four Score, multiplexed on $4016) button state.

p4: Buttons

Player 4 (Four Score, multiplexed on $4017) button state.

expansion: u8

Reserved expansion-port byte (currently always 0).

Implementations

impl FrameInput

pub const fn new(p1: Buttons, p2: Buttons) -> Self

Build a two-controller frame (players 3/4 released, no expansion byte).

pub const fn four_players( p1: Buttons, p2: Buttons, p3: Buttons, p4: Buttons, ) -> Self

v2.9.8 — build a four-controller frame (no expansion byte).

pub const fn port(&self, port: usize) -> Buttons

v2.9.8 — the buttons on controller port (0-3 = players 1-4).

Panics

Panics if port is not in 0..=3, matching Nes::set_buttons.

pub const fn port_mut(&mut self, port: usize) -> &mut Buttons

v2.9.8 — mutable access to controller port (0-3 = players 1-4).

Panics

Panics if port is not in 0..=3.

pub const fn apply_to(&self, nes: &mut Nes)

v2.9.8 — drive all four controller ports of nes from this frame.

Ports 2 and 3 are only polled while the Four Score is plugged in, so setting them on a two-pad machine changes nothing it reads.

pub const fn held_on(nes: &Nes) -> Self

v2.9.8 — the input currently held on all four ports of nes.

Trait Implementations

impl Clone for FrameInput

fn clone(&self) -> FrameInput

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for FrameInput

impl Debug for FrameInput

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FrameInput

fn default() -> FrameInput

Returns the “default value” for a type.

impl Eq for FrameInput

impl PartialEq for FrameInput

fn eq(&self, other: &FrameInput) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for FrameInput