Module vector_tile

Vector tile coordinate handling and conversions

This module provides functionality for converting between different coordinate systems used in vector tile mapping:

• WGS84 coordinates (latitude/longitude)
• Pixel coordinates within tiles
• Tile coordinates (x, y, zoom)

Vector Tiles

Vector tiles are square vector images, typically 256×256 pixels, that together create a slippy map. The tile coordinate system:

• Origin (0,0) is at the top-left corner
• Tiles are addressed by x, y coordinates and zoom level
• At zoom level z, the map consists of 2^z × 2^z tiles

Coordinate Systems

Tile Coordinates

• x: Column number from left (0 to 2^zoom - 1)
• y: Row number from top (0 to 2^zoom - 1)
• zoom: Detail level (typically 0-20)

Pixel Coordinates

• Within each tile: 0 to TILE_SIZE-1 (typically 256)
• Global: 0 to 2^zoom * TILE_SIZE

Examples

use toolbox_rs::vector_tile::{degree_to_pixel_lon, degree_to_pixel_lat};
use toolbox_rs::wgs84::{FloatLatitude, FloatLongitude};

// Convert Dresden coordinates to pixels at zoom level 12
let lat = FloatLatitude(51.0504);
let lon = FloatLongitude(13.7373);
let zoom = 12;

let px_x = degree_to_pixel_lon(lon, zoom);
let px_y = degree_to_pixel_lat(lat, zoom);

Implementation Notes

• Pixel coordinates increase from west to east (x) and north to south (y)
• The equator is centered at y = 2^(zoom-1) * TILE_SIZE
• Greenwich meridian is centered at x = 2^(zoom-1) * TILE_SIZE

Structs

TileBounds

Functions

coordinate_to_tile_number

Converts WGS84 coordinates to tile coordinates at a given zoom level

degree_to_pixel_lat

Converts latitude in degrees to pixel y-coordinate

degree_to_pixel_lon

Converts longitude in degrees to pixel x-coordinate

get_tile_bounds

Calculates the WGS84 coordinate bounds of a map tile

linestring_to_tile_coords

Converts WGS84 coordinates to tile-local pixel coordinates

pixel_to_degree

Converts pixel coordinates to degrees