Struct OutputParamsWatch 

pub struct OutputParamsWatch { /* private fields */ }

Consumer-side helper for the Decoder::output_params / Decoder::output_params_generation contract: folds the decoder’s output description into a stream’s CodecParameters once, and again only when the decoder signals a mid-stream change — one integer compare per frame otherwise.

Call observe after every successful receive_frame (the first call always reads the description; later calls re-read only when the generation moved). Call prime before the first frame when the shape is needed up front (to size a renderer, pick a converter); it merges whatever the decoder already knows without consuming the first-frame read, since the description may still be refined up to the first frame.

fn pump(dec: &mut dyn Decoder, stream: &mut CodecParameters) -> oxideav_core::Result<()> {
    let mut watch = OutputParamsWatch::new();
    while let Ok(_frame) = dec.receive_frame() {
        if watch.observe(&*dec, stream) {
            // shape changed (or was first resolved): reconfigure
            // the converter / renderer from `stream` here.
        }
    }
    Ok(())
}

Implementations

impl OutputParamsWatch

pub const fn new() -> Self

A watch that has not read the decoder yet.

pub fn observe<D: Decoder + ?Sized>( &mut self, decoder: &D, stream: &mut CodecParameters, ) -> bool

Call after a successful receive_frame. Re-reads Decoder::output_params on the first call and whenever Decoder::output_params_generation differs from the value of the last read, merging it into stream through CodecParameters::merge_output_params. Returns true when that changed an output-describing field of stream.

A decoder that still answers None leaves stream untouched and is asked again on the next call.

pub fn prime<D: Decoder + ?Sized>( &self, decoder: &D, stream: &mut CodecParameters, ) -> bool

Merge what the decoder already knows into stream without recording a read — for use before the first frame. Returns true when an output-describing field of stream changed.

pub fn reset(&mut self)

Forget the last read so the next observe re-reads unconditionally (e.g. after swapping the decoder).

Trait Implementations

impl Clone for OutputParamsWatch

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for OutputParamsWatch

impl Debug for OutputParamsWatch

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

Formats the value using the given formatter.

impl Default for OutputParamsWatch

fn default() -> Self

Returns the “default value” for a type.

impl Eq for OutputParamsWatch

impl PartialEq for OutputParamsWatch

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for OutputParamsWatch