This project is part of the @thi.ng/umbrella monorepo.

• About
  • Columns
  • Diagonal
  • Hilbert curve
  • Interleave columns
  • Interleave rows
  • Random
  • Rows
  • Outward spiral
  • Z-curve
  • Zigzag columns
  • Zigzag diagonal
  • Zigzag rows
  • Miscellaneous
  • Status
  • Related packages
• Installation
• Dependencies
• Usage examples
• API
• Authors
• License

About

2D grid iterators w/ multiple orderings.

Provides the 15 following orderings to generate grid coordinates and additional iterators for shape rasterization:

Columns

Source

Also see the filtered version columnEnds2d(), which only includes the end points of each column.

Diagonal

Source

Also see the filtered version diagonalEnds2d(), which only includes the end points of the diagonals.

Hilbert curve

Source

Interleave columns

Source

Supports custom strides... example uses step = 4

Interleave rows

Source

Supports custom strides... example uses step = 4

Random

Source

Supports custom PRNG implementations via IRandom interface defined in @thi.ng/random

Rows

Source

Also see the filtered version rowEnds2d(), which only includes the end points of each row.

Outward spiral

Source

Z-curve

Source

Zigzag columns

Source

Zigzag diagonal

Source

Zigzag rows

Source

Some functions have been ported from Christopher Kulla's Java-based Sunflow renderer.

For more basic 2D/3D grid iteration, also see range2d() & range3d() in @thi.ng/transducers.

Miscellaneous

Additionally, the following shape iterators are available:

• circle (Bresenham)
• hline
• vline
• line (Bresenham)

Status

STABLE - used in production

Search or submit any issues for this package

Related packages

• @thi.ng/morton - Z-order curve / Morton encoding, decoding & range extraction for arbitrary dimensions
• @thi.ng/transducers - Lightweight transducer implementations for ES6 / TypeScript

Installation

yarn add @thi.ng/grid-iterators

ES module import:

<script type="module" src="https://cdn.skypack.dev/@thi.ng/grid-iterators"></script>

Skypack documentation

For Node.js REPL:

# with flag only for < v16
node --experimental-repl-await

> const gridIterators = await import("@thi.ng/grid-iterators");

Package sizes (gzipped, pre-treeshake): ESM: 1.50 KB

Dependencies

• @thi.ng/arrays
• @thi.ng/binary
• @thi.ng/morton
• @thi.ng/random
• @thi.ng/transducers

Usage examples

Several demos in this repo's /examples directory are using this package.

A selection:

Screenshot	Description	Live demo	Source
	Visualization of different grid iterator strategies	Demo	Source

API

Generated API docs

import * as gi from "@thi.ng/grid-iterators";

[...gi.zigzagRows2d(4, 4)]

// [
//   [ 0, 0 ], [ 1, 0 ], [ 2, 0 ], [ 3, 0 ],
//   [ 3, 1 ], [ 2, 1 ], [ 1, 1 ], [ 0, 1 ],
//   [ 0, 2 ], [ 1, 2 ], [ 2, 2 ], [ 3, 2 ],
//   [ 3, 3 ], [ 2, 3 ], [ 1, 3 ], [ 0, 3 ]
// ]

Authors

Karsten Schmidt

If this project contributes to an academic publication, please cite it as:

@misc{thing-grid-iterators,
  title = "@thi.ng/grid-iterators",
  author = "Karsten Schmidt",
  note = "https://thi.ng/grid-iterators",
  year = 2019
}

License

© 2019 - 2021 Karsten Schmidt // Apache Software License 2.0