Crate copc_temporal 

Reader for the COPC Temporal Index Extension.

When a COPC file contains data from multiple survey passes over the same area, a spatial query alone returns points from every pass that touched that region. The temporal index extension adds per-node GPS time metadata so that clients can filter by time before decompressing any point data.

This crate reads the temporal index incrementally via ByteSource, matching the streaming design of copc_streaming.

Quick start

use copc_streaming::{CopcStreamingReader, FileSource};
use copc_temporal::{GpsTime, TemporalCache};

let mut reader = CopcStreamingReader::open(
    FileSource::open("survey.copc.laz")?,
).await?;
reader.load_all_hierarchy().await?;

// Load the temporal index (returns None if the file has no temporal EVLR).
// from_reader loads only the header and root page — not the entire index.
let mut temporal = match TemporalCache::from_reader(&reader).await? {
    Some(t) => t,
    None => return Ok(()), // no temporal index in this file
};

// Define the time window we care about.
let start = GpsTime(1_000_000.0);
let end   = GpsTime(1_000_010.0);

// Load only the temporal pages whose subtree overlaps our time range.
// Pages covering other time periods are never fetched.
temporal.load_pages_for_time_range(reader.source(), start, end).await?;

// Find octree nodes that overlap the time window.
let nodes = temporal.nodes_in_range(start, end);

for entry in &nodes {
    // Estimate the point sub-range within the node.
    let hier = reader.get(&entry.key).unwrap();
    let range = entry.estimate_point_range(
        start, end, temporal.stride(), hier.point_count as u32,
    );
    println!("{:?}: points {}..{}", entry.key, range.start, range.end);
}

Incremental page loading

Like the spatial hierarchy, the temporal index is organised in pages. TemporalCache::from_reader loads the header and root page. You can then:

• call TemporalCache::load_pages_for_time_range to fetch only the pages whose subtree time bounds overlap your query — skipping irrelevant subtrees entirely, or
• call TemporalCache::load_all_pages to fetch everything at once.

Structs

Aabb

Axis-aligned bounding box.

GpsTime

Newtype over f64 GPS time. Implements Copy, PartialEq, PartialOrd.

NodeTemporalEntry

Per-node temporal data: a set of sampled GPS timestamps.

TemporalCache

Incrementally-loaded temporal index cache.

TemporalHeader

Header of the temporal index EVLR (32 bytes).

VoxelKey

Octree node key: (level, x, y, z).

Enums

TemporalError

Errors that can occur when reading the temporal index.

Traits

ByteSource

Async random-access byte source.