@animech-public/playcanvas/build/playcanvas.dbg/src/core/math/bit-packing.js

PlayCanvas WebGL game engine

/**
 * BitPacking API - functionality for operating on values stored as bits in a number.
 *
 * @namespace
 * @ignore
 */
const BitPacking = {
  /**
   * Sets a value to specified bits of a number.
   *
   * @param {number} storage - Number to store the bits into.
   * @param {number} value - Value to store.
   * @param {number} shift - Number of bits to shift the value.
   * @param {number} [mask] - Mask for the value to limit the number of storage bits. Defaults to 1.
   * @returns {number} Returns the storage updated with the value.
   */
  set(storage, value, shift, mask = 1) {
    // clear the space
    const data = storage & ~(mask << shift);

    // set the bits
    return data | value << shift;
  },
  /**
   * Gets the value of specified bits from a number.
   *
   * @param {number} storage - Number to extract the bits from.
   * @param {number} shift - Number of bits to shift the mask.
   * @param {number} [mask] - Mask for the value to limit the number of storage bits. Defaults to 1.
   * @returns {number} Returns the extracted value.
   */
  get(storage, shift, mask = 1) {
    return storage >> shift & mask;
  },
  /**
   * Tests if all specified bits are set.
   *
   * @param {number} storage - Number to test.
   * @param {number} shift - Number of bits to shift the mask.
   * @param {number} [mask] - Mask to limit the number of storage bits. Defaults to 1.
   * @returns {boolean} Returns true if all bits in the mask are set in the storage.
   */
  all(storage, shift, mask = 1) {
    const shifted = mask << shift;
    return (storage & shifted) === shifted;
  },
  /**
   * Tests if any specified bits are set.
   *
   * @param {number} storage - Number to test.
   * @param {number} shift - Number of bits to shift the mask.
   * @param {number} [mask] - Mask to limit the number of storage bits. Defaults to 1.
   * @returns {boolean} Returns true if any bits in the mask are set in the storage.
   */
  any(storage, shift, mask = 1) {
    return (storage & mask << shift) !== 0;
  }
};

export { BitPacking };