jgdtrans for Rust

Unofficial coordinate transformer by Gridded Correction Parameter which Geospatial Information Authority of Japan (GIAJ, formerly GSIJ) distributing for Rust.

国土地理院が公開している .par ファイルによる変換（逆変換）の非公式な実装です。

Features:

• Offline transformation (no web API)
  • オフライン変換（web API 不使用）
• Supports both original forward/backward transformation
  • 順変換と逆変換の両方をサポート
• Supports verified backward transformation
  • 精度を保証した逆変換のサポート
• Supports all TKY2JGD, PatchJGD, PatchJGD(H), HyokoRev, SemiDynaEXE and POS2JGD (geonetF3 and ITRF2014)
  • For example, Tokyo Datum to JGD2000 (EPSG:4301 to EPSG:4612) and JGD2000 to JGD2011 (EPSG:4612 to EPSG:6668)
  • 上記の全てをサポート
• Clean implementation
  • 保守が容易な実装
• No dependency
  • 依存パッケージなし

jdgtrans requires nightly channel of Rust, it depends on a float_next_up_down feature.

Optional Features

• serde: supports serialization/deserialization by serde crate, this requires dependency on serde.

Usage

This package does not contain parameter files, download it from GIAJ.

このパッケージはパラメータファイルを提供しません。公式サイトよりダウンロードしてください。

Sample code:

use std::error::Error;
use std::fs;

use jgdtrans::{Point, Transformer, Format};

fn main() -> Result<(), Box<dyn Error>> {
    // Deserialize par-formatted file, e.g. SemiDyna2023.par
    let s = fs::read_to_string("SemiDyna2023.par").expect("file not found 'SemiDyna2023.par'");
    let tf = Transformer::from_str(&s, Format::SemiDynaEXE)?;

    // Make the origin of transformation
    let origin = Point::new_unchecked(35.0, 135.0, 2.34);
    // Prints Point { latitude: 35.0, longitude: 135.0, altitude: 2.34 }
    println!("{origin:?}");

    // Perform forward transformation resulting a Point
    let result = tf.forward(&origin)?;
    // Prints Point { latitude: 34.99999831111111, longitude: 135.00000621666666, altitude: 2.33108 }
    println!("{result:?}");

    // Perform backward transformation
    let p = tf.backward(&result)?;
    // Prints Point { latitude: 35.0, longitude: 135.0, altitude: 2.34 }
    println!("{p:?}");

    // Perform backward transformation compatible to the GIAJ web app/APIs
    let q = tf.backward_compat(&result)?;
    // Prints Point { latitude: 34.999999999999986, longitude: 135.0, altitude: 2.339999999105295 }
    println!("{q:?}");

    Ok(())
}

Licence

MIT or Apache-2.0

Reference

1. Geospatial Information Authority of Japan (GIAJ, 国土地理院): https://www.gsi.go.jp/, (English) https://www.gsi.go.jp/ENGLISH/.
2. TKY2JGD for Windows Ver.1.3.79 (reference implementation): https://www.gsi.go.jp/sokuchikijun/tky2jgd_download.html, released under 国土地理院コンテンツ利用規約 which compatible to CC BY 4.0.
3. Other implementation: Python https://github.com/paqira/jgdtrans-py, Java https://github.com/paqira/jgdtrans-java, JavaScript/TypeScript https://github.com/paqira/jgdtrans-js.