Struct TileMeta 

pub struct TileMeta {
    pub qa: Option<BTreeMap<String, (f64, f64)>>,
    pub sorted: Option<bool>,
    pub t0: Option<i64>,
    pub vb: Option<u32>,
    pub vt: Option<(i64, u32)>,
}

The per-tile-varying metadata a v2 frame carries in its TILE_META section instead of the (now dataset-constant, template-resident) Arrow schema metadata. Canonical serialization (design §4.3): JSON, keys sorted — field order below IS alphabetical and the qa map is a BTreeMap — no whitespace. Readers MUST ignore unknown keys (serde’s default here), so the section can evolve additively. Presence rules: a key is present iff the corresponding feature is (qa omits non-quantized columns entirely; t0 iff a start-time column exists; vt iff delta-encoded vertex_time; vb iff a value matrix).

Fields

qa: Option<BTreeMap<String, (f64, f64)>>

Per-property attribute-quantization affines, column → [o, s] (value = o + q*s) — the v1 stt:qa field metadata, hoisted.

sorted: Option<bool>

Rows are stable-sorted by start_time (always true from this writer; a flag so Stage III can demote the sort without a frame bump).

t0: Option<i64>

The v1 stt:time_offset_ms schema key: minimum feature start-time.

vb: Option<u32>

The v1 stt:vertex_value_buckets schema key.

vt: Option<(i64, u32)>

The v1 stt:vertex_time_origin_ms / stt:vertex_time_step_ms pair, as [origin_ms, step_ms].

Trait Implementations

impl Clone for TileMeta

fn clone(&self) -> TileMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TileMeta

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

Formats the value using the given formatter.

impl Default for TileMeta

fn default() -> TileMeta

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for TileMeta

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for TileMeta

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.