Struct MixRecord 

pub struct MixRecord {
    pub mixed: f32,
    pub external: f32,
    pub pulse1: u8,
    pub pulse2: u8,
    pub triangle: u8,
    pub noise: u8,
    pub dmc: u8,
}

The five channel outputs that went into one mixed CPU-cycle sample, plus the result.

Channel values are the raw pre-mix outputs each channel presented — 0-15 for the two pulses, the triangle and the noise, 0-127 for the DMC — which is what the non-linear mixer consumes. They are NOT scaled by the frontend’s mixer gains: those are a presentation control, and recording post-gain values would make the record describe the user’s slider rather than the chip.

Fields

mixed: f32

The mixed sample handed to the band-limited decimator, including any expansion audio.

external: f32

The expansion-audio contribution, RAW (0.0 on a cartridge without one).

Raw in the same sense as the five channel fields: before the frontend’s expansion gain and before the mixer mask. So on a muted or attenuated expansion channel this reports what the cartridge produced, not what reached mixed — consistent with pulse1 reporting a muted pulse’s output rather than zero. Both mix paths record this same raw value; an earlier revision recorded the gained value on one of them, which review caught.

pulse1: u8

Pulse 1 output, 0-15.

pulse2: u8

Pulse 2 output, 0-15.

triangle: u8

Triangle output, 0-15.

noise: u8

Noise output, 0-15.

dmc: u8

DMC output, 0-127.

Implementations

impl MixRecord

pub fn dominant(&self) -> Option<usize>

Which channel contributed most to this sample, as an index into the conventional order (0 = pulse 1 … 4 = DMC), or None when every channel is silent.

Compares each channel’s share of its own full scale rather than its raw value, because the raw values are not commensurable: a DMC 127 and a pulse 15 are both “full scale” on different scales.

That normalisation is linear — value / max — and deliberately does NOT model the non-linear mixer, which an earlier draft of this comment claimed it did. The two give different answers, since the mixer weights the triangle/noise/DMC group differently from the pulses and is not proportional in either. This reports which channel is working hardest relative to what it can do, which is the question a user pointing at a cycle is asking; attributing loudness in the final mix would be a different function, and calling this one that would be a false label on a correct computation.

Trait Implementations

impl Clone for MixRecord

fn clone(&self) -> MixRecord

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MixRecord

impl Debug for MixRecord

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

Formats the value using the given formatter.

impl Default for MixRecord

fn default() -> MixRecord

Returns the “default value” for a type.

impl PartialEq for MixRecord

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for MixRecord