Function read_geometry

nodedb-spatial/src/wkb.rs:147–228

(data: &[u8], cursor: &mut usize)

// ── Read helpers ──

fn read_geometry(data: &[u8], cursor: &mut usize) -> Option<Geometry> {
    let byte_order = read_u8(data, cursor)?;
    let is_le = byte_order == 1;
    let wkb_type = read_u32(data, cursor, is_le)?;

    match wkb_type {
        WKB_POINT => {
            let x = read_f64(data, cursor, is_le)?;
            let y = read_f64(data, cursor, is_le)?;
            Some(Geometry::Point {
                coordinates: [x, y],
            })
        }
        WKB_LINESTRING => {
            let n = read_u32(data, cursor, is_le)? as usize;
            let coords = read_coords(data, cursor, n, is_le)?;
            Some(Geometry::LineString {
                coordinates: coords,
            })
        }
        WKB_POLYGON => {
            let num_rings = read_u32(data, cursor, is_le)? as usize;
            let mut rings = Vec::with_capacity(num_rings);
            for _ in 0..num_rings {
                let n = read_u32(data, cursor, is_le)? as usize;
                let ring = read_coords(data, cursor, n, is_le)?;
                rings.push(ring);
            }
            Some(Geometry::Polygon { coordinates: rings })
        }
        WKB_MULTIPOINT => {
            let count = read_u32(data, cursor, is_le)? as usize;
            let mut coords = Vec::with_capacity(count);
            for _ in 0..count {
                let inner = read_geometry(data, cursor)?;
                if let Geometry::Point { coordinates } = inner {
                    coords.push(coordinates);
                } else {
                    return None;
                }
            }
            Some(Geometry::MultiPoint {
                coordinates: coords,
            })
        }
        WKB_MULTILINESTRING => {
            let count = read_u32(data, cursor, is_le)? as usize;
            let mut lines = Vec::with_capacity(count);
            for _ in 0..count {
                let inner = read_geometry(data, cursor)?;
                if let Geometry::LineString { coordinates } = inner {
                    lines.push(coordinates);
                } else {
                    return None;
                }
            }
            Some(Geometry::MultiLineString { coordinates: lines })
        }