zodiacal 0.4.1

A blind astrometry plate-solving library
Documentation 
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pub mod builder;
pub mod live;
pub mod source;
pub mod store;

use crate::kdtree::KdTree;
use crate::quads::{DIMCODES, Quad};

pub use live::{DropReport, EnsureReport, LiveIndex};
pub use source::{HealpixCell, IndexFragment, IndexSource, ZdclFile};

/// Metadata for a star in the index.
#[derive(Debug, Clone)]
pub struct IndexStar {
    pub catalog_id: u64,
    pub ra: f64,
    pub dec: f64,
    pub mag: f64,
}

/// Build metadata stored in a v2 index file.
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct IndexMetadata {
    pub scale_lower_arcsec: f64,
    pub scale_upper_arcsec: f64,
    pub n_stars: usize,
    pub n_quads: usize,
    pub max_stars_per_cell: usize,
    pub uniformize_depth: u8,
    pub quad_depth: u8,
    pub passes: usize,
    pub max_reuse: usize,
    pub build_timestamp: u64,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub catalog_path: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub band_index: Option<usize>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub scale_factor: Option<f64>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub mag_range: Option<(f64, f64)>,
}

/// A complete index: stars + quads + KD-trees for fast search.
pub struct Index {
    /// KD-tree over star positions (3D unit vectors).
    pub star_tree: KdTree<3>,
    /// Star metadata.
    pub stars: Vec<IndexStar>,
    /// KD-tree over quad codes (4D).
    pub code_tree: KdTree<{ DIMCODES }>,
    /// Quad definitions.
    pub quads: Vec<Quad>,
    /// Scale range this index covers (radians).
    pub scale_lower: f64,
    pub scale_upper: f64,
    /// Build metadata (present in v2+ index files).
    pub metadata: Option<IndexMetadata>,
}

impl std::fmt::Debug for Index {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Index")
            .field("stars", &self.stars.len())
            .field("quads", &self.quads.len())
            .field("scale_lower", &self.scale_lower)
            .field("scale_upper", &self.scale_upper)
            .finish()
    }
}

impl From<IndexFragment> for Index {
    /// Build a runnable `Index` (with reconstructed KD-trees) from an
    /// `IndexFragment` returned by `IndexSource::load_full` or
    /// `IndexSource::load_cells`. Tree-reconstruction is O(N log N); for
    /// a typical regional load (~10 k stars) it costs a few milliseconds.
    fn from(frag: IndexFragment) -> Self {
        use crate::geom::sphere::radec_to_xyz;

        let star_points: Vec<[f64; 3]> = frag
            .stars
            .iter()
            .map(|s| radec_to_xyz(s.ra, s.dec))
            .collect();
        let star_indices: Vec<usize> = (0..frag.stars.len()).collect();
        let star_tree = KdTree::<3>::build(star_points, star_indices);

        let code_indices: Vec<usize> = (0..frag.codes.len()).collect();
        let code_tree = KdTree::<{ DIMCODES }>::build(frag.codes, code_indices);

        Self {
            star_tree,
            stars: frag.stars,
            code_tree,
            quads: frag.quads,
            scale_lower: frag.scale_lower,
            scale_upper: frag.scale_upper,
            metadata: frag.metadata,
        }
    }
}