Struct ZapperState 

pub struct ZapperState { /* private fields */ }

The NES Zapper light-gun overlay state.

Models the NES variant: bit 3 = light sensed (0 detected / 1 not), bit 4 = trigger (1 pulled). Light detection samples the PPU framebuffer luminance at the aim point once per frame (a frame-granular model — see light_seen).

Implementations

impl ZapperState

pub const fn new() -> Self

New zapper aimed off-screen, trigger released, no light.

pub const fn set(&mut self, x: u16, y: u16, trigger: bool)

Update the live aim point + trigger state.

pub fn sample_light(&mut self, framebuffer: &[u8])

Sample the framebuffer luminance at the aim point, setting light_seen if the pixel is bright enough. framebuffer is the PPU’s RGBA8 256x240 buffer. Called once per frame by the bus after the frame completes.

pub const fn read(&self) -> u8

The device byte for a $4016/$4017 access. Bit 3 = light (0 detected / 1 not), bit 4 = trigger (1 pulled). Independent of the strobe (the Zapper has no shift register). The caller ORs in the open-bus upper bits.

pub const fn from_parts(x: u16, y: u16, trigger: bool, light_seen: bool) -> Self

Reconstruct from save-state parts.

pub const fn x_raw(&self) -> u16

Raw aim X (save-state).

pub const fn y_raw(&self) -> u16

Raw aim Y (save-state).

pub const fn trigger_raw(&self) -> bool

Raw trigger state (save-state).

pub const fn light_seen_raw(&self) -> bool

Raw light-seen state (save-state).

Trait Implementations

impl Clone for ZapperState

fn clone(&self) -> ZapperState

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ZapperState

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

Formats the value using the given formatter.

impl Default for ZapperState

fn default() -> ZapperState

Returns the “default value” for a type.

impl Copy for ZapperState