gpu-curtains/dist/esm/math/Box3.mjs

gpu-curtains is a 3D WebGPU rendering engine. It can be used as a standalone 3D engine, but also includes extra classes focused on mapping 3d objects to DOM elements; It allows users to synchronize values such as position, sizing, or scale between them.

import { Vec3 } from './Vec3.mjs';
import { Mat4 } from './Mat4.mjs';

const points = [new Vec3(), new Vec3(), new Vec3(), new Vec3(), new Vec3(), new Vec3(), new Vec3(), new Vec3()];
class Box3 {
  /**
   * Box3 constructor
   * @param min - min {@link Vec3 | vector} of the {@link Box3}
   * @param max - max {@link Vec3 | vector} of the {@link Box3}
   */
  constructor(min = new Vec3(Infinity), max = new Vec3(-Infinity)) {
    this.min = min;
    this.max = max;
  }
  /**
   * Set a {@link Box3} from two min and max {@link Vec3 | vectors}
   * @param min - min {@link Vec3 | vector} of the {@link Box3}
   * @param max - max {@link Vec3 | vector} of the {@link Box3}
   */
  set(min = new Vec3(Infinity), max = new Vec3(-Infinity)) {
    this.min.copy(min);
    this.max.copy(max);
    return this;
  }
  /**
   * Check whether the {@link Box3} min and max values have actually been set
   */
  isEmpty() {
    return this.max.x < this.min.x || this.max.y < this.min.y || this.max.z < this.min.z;
  }
  /**
   * Copy a {@link Box3} into this {@link Box3}.
   * @param box - {@link Box3} to copy
   */
  copy(box) {
    this.set(box.min.clone(), box.max.clone());
    return this;
  }
  /**
   * Clone this {@link Box3}
   * @returns - cloned {@link Box3}
   */
  clone() {
    return new Box3().copy(this);
  }
  /**
   * Get the {@link Box3} center
   * @readonly
   * @returns - {@link Vec3 | center vector} of the {@link Box3}
   */
  get center() {
    return this.max.clone().add(this.min).multiplyScalar(0.5);
  }
  /**
   * Get the {@link Box3} size
   * @readonly
   * @returns - {@link Vec3 | size vector} of the {@link Box3}
   */
  get size() {
    return this.max.clone().sub(this.min);
  }
  /**
   * Get the {@link Box3} radius
   * @readonly
   * @returns - radius of the {@link Box3}
   */
  get radius() {
    return this.max.distance(this.min) * 0.5;
  }
  /**
   * Apply a {@link Mat4 | matrix} to a {@link Box3}
   * Useful to apply a transformation {@link Mat4 | matrix} to a {@link Box3}
   * @param matrix - {@link Mat4 | matrix} to use
   * @param transformedBox - {@link Box3 | transformed Box3} to set
   * @returns - the {@link Box3 | transformed Box3} after {@link Mat4 | matrix} application
   */
  applyMat4(matrix = new Mat4(), transformedBox = new Box3()) {
    if (this.isEmpty()) return this;
    const corners = [];
    if (this.min.z === this.max.z) {
      corners[0] = points[0].set(this.min.x, this.min.y, this.min.z).applyMat4(matrix);
      corners[1] = points[1].set(this.min.x, this.max.y, this.min.z).applyMat4(matrix);
      corners[2] = points[2].set(this.max.x, this.min.y, this.min.z).applyMat4(matrix);
      corners[3] = points[3].set(this.max.x, this.max.y, this.min.z).applyMat4(matrix);
      corners[4] = points[4].set(0, 0, 0).applyMat4(matrix);
    } else {
      corners[0] = points[0].set(this.min.x, this.min.y, this.min.z).applyMat4(matrix);
      corners[1] = points[1].set(this.min.x, this.min.y, this.max.z).applyMat4(matrix);
      corners[2] = points[2].set(this.min.x, this.max.y, this.min.z).applyMat4(matrix);
      corners[3] = points[3].set(this.min.x, this.max.y, this.max.z).applyMat4(matrix);
      corners[4] = points[4].set(this.max.x, this.min.y, this.min.z).applyMat4(matrix);
      corners[5] = points[5].set(this.max.x, this.min.y, this.max.z).applyMat4(matrix);
      corners[6] = points[6].set(this.max.x, this.max.y, this.min.z).applyMat4(matrix);
      corners[7] = points[7].set(this.max.x, this.max.y, this.max.z).applyMat4(matrix);
    }
    for (let i = 0, cornersCount = corners.length; i < cornersCount; i++) {
      transformedBox.min.min(corners[i]);
      transformedBox.max.max(corners[i]);
    }
    return transformedBox;
  }
}

export { Box3 };