Light Bitmap

A minimal, fixed-size bitmap library written in pure Rust.
no_std, no heap / alloc, no unsafe — just core.

Designed for use in embedded and resource-constrained environments.

BitMap is the main struct in this library. Its features are listed below.

Examples

use light_bitmap::{bucket_count, BitMap};

const BIT_COUNT: usize = 10;
let mut bitmap = BitMap::<BIT_COUNT, { bucket_count(BIT_COUNT) }>::new();
assert_eq!(bitmap.popcount(), 0);
assert!(!bitmap.is_set(3));
bitmap.set(3);
assert!(bitmap.is_set(3));
assert_eq!(bitmap.popcount(), 1);

Use Cases

• Embedded development
• Applications that need a compact, stack-only bitmap with no dynamic allocation
• Timing-sensitive systems where allocation unpredictability must be avoided
• Does not support SIMD or parallel execution, so it's not ideal for cases where performance needs to be fully maxed out

Features

• #![no_std] compatible
• Bit-level operations on a fixed number of bits
• No heap allocations (stack-only)
• Const-generic API: BitMap<const BIT_COUNT, const BUCKET_COUNT>
• Efficient iteration over all, set or unset bits:
  • iter() (all bits as bools)
  • iter_ones() (indices of set bits)
  • iter_zeros() (indices of unset bits)
• Support for bitwise ops:
  • &, |, ^, !
  • <<, >>
  • &=, |=, ^=, <<=, >>=
• Range operations: set_range, unset_range
• Logical operations: popcount, first_set_bit
• Rotation support: rotate_left, rotate_right

MIT licensed. Maintained with love for bitwise enthusiasts.