/**
 * @import { Mat4 } from './mat4.js'
 * @import { Quat } from './quat.js'
 */
/**
 * A 3x3 matrix.
 *
 * @category Math
 */
export class Mat3 {
    /**
     * A constant matrix set to the identity.
     *
     * @type {Mat3}
     * @readonly
     */
    static readonly IDENTITY: Mat3;
    /**
     * A constant matrix with all elements set to 0.
     *
     * @type {Mat3}
     * @readonly
     */
    static readonly ZERO: Mat3;
    /**
     * Matrix elements in the form of a flat array.
     *
     * @type {Float32Array}
     */
    data: Float32Array;
    /**
     * Creates a duplicate of the specified matrix.
     *
     * @returns {this} A duplicate matrix.
     * @example
     * const src = new pc.Mat3().translate(10, 20, 30);
     * const dst = src.clone();
     * console.log("The two matrices are " + (src.equals(dst) ? "equal" : "different"));
     */
    clone(): this;
    /**
     * Copies the contents of a source 3x3 matrix to a destination 3x3 matrix.
     *
     * @param {Mat3} rhs - A 3x3 matrix to be copied.
     * @returns {Mat3} Self for chaining.
     * @example
     * const src = new pc.Mat3().translate(10, 20, 30);
     * const dst = new pc.Mat3();
     * dst.copy(src);
     * console.log("The two matrices are " + (src.equals(dst) ? "equal" : "different"));
     */
    copy(rhs: Mat3): Mat3;
    /**
     * Copies the contents of a source array[9] to a destination 3x3 matrix.
     *
     * @param {number[]} src - An array[9] to be copied.
     * @returns {Mat3} Self for chaining.
     * @example
     * const dst = new pc.Mat3();
     * dst.set([0, 1, 2, 3, 4, 5, 6, 7, 8]);
     */
    set(src: number[]): Mat3;
    /**
     * Extracts the x-axis from the specified matrix.
     *
     * @param {Vec3} [x] - The vector to receive the x axis of the matrix.
     * @returns {Vec3} The x-axis of the specified matrix.
     */
    getX(x?: Vec3): Vec3;
    /**
     * Extracts the y-axis from the specified matrix.
     *
     * @param {Vec3} [y] - The vector to receive the y axis of the matrix.
     * @returns {Vec3} The y-axis of the specified matrix.
     */
    getY(y?: Vec3): Vec3;
    /**
     * Extracts the z-axis from the specified matrix.
     *
     * @param {Vec3} [z] - The vector to receive the z axis of the matrix.
     * @returns {Vec3} The z-axis of the specified matrix.
     */
    getZ(z?: Vec3): Vec3;
    /**
     * Reports whether two matrices are equal.
     *
     * @param {Mat3} rhs - The other matrix.
     * @returns {boolean} True if the matrices are equal and false otherwise.
     * @example
     * const a = new pc.Mat3().translate(10, 20, 30);
     * const b = new pc.Mat3();
     * console.log("The two matrices are " + (a.equals(b) ? "equal" : "different"));
     */
    equals(rhs: Mat3): boolean;
    /**
     * Reports whether the specified matrix is the identity matrix.
     *
     * @returns {boolean} True if the matrix is identity and false otherwise.
     * @example
     * const m = new pc.Mat3();
     * console.log("The matrix is " + (m.isIdentity() ? "identity" : "not identity"));
     */
    isIdentity(): boolean;
    /**
     * Sets the matrix to the identity matrix.
     *
     * @returns {Mat3} Self for chaining.
     * @example
     * m.setIdentity();
     * console.log("The matrix is " + (m.isIdentity() ? "identity" : "not identity"));
     */
    setIdentity(): Mat3;
    /**
     * Converts the matrix to string form.
     *
     * @returns {string} The matrix in string form.
     * @example
     * const m = new pc.Mat3();
     * // Outputs [1, 0, 0, 0, 1, 0, 0, 0, 1]
     * console.log(m.toString());
     */
    toString(): string;
    /**
     * Generates the transpose of the specified 3x3 matrix.
     *
     * @param {Mat3} [src] - The matrix to transpose. If not set, the matrix is transposed in-place.
     * @returns {Mat3} Self for chaining.
     * @example
     * const m = new pc.Mat3();
     *
     * // Transpose in place
     * m.transpose();
     */
    transpose(src?: Mat3): Mat3;
    /**
     * Converts the specified 4x4 matrix to a Mat3.
     *
     * @param {Mat4} m - The 4x4 matrix to convert.
     * @returns {Mat3} Self for chaining.
     */
    setFromMat4(m: Mat4): Mat3;
    /**
     * Sets this matrix to the given quaternion rotation.
     *
     * @param {Quat} r - A quaternion rotation.
     * @returns {Mat3} Self for chaining.
     * @example
     * const r = new pc.Quat(1, 2, 3, 4).normalize();
     *
     * const m = new pc.Mat4();
     * m.setFromQuat(r);
     */
    setFromQuat(r: Quat): Mat3;
    /**
     * Set the matrix to the inverse of the specified 4x4 matrix.
     *
     * @param {Mat4} src - The 4x4 matrix to invert.
     * @returns {Mat3} Self for chaining.
     *
     * @ignore
     */
    invertMat4(src: Mat4): Mat3;
    /**
     * Transforms a 3-dimensional vector by a 3x3 matrix.
     *
     * @param {Vec3} vec - The 3-dimensional vector to be transformed.
     * @param {Vec3} [res] - An optional 3-dimensional vector to receive the result of the
     * transformation.
     * @returns {Vec3} The input vector v transformed by the current instance.
     */
    transformVector(vec: Vec3, res?: Vec3): Vec3;
}
import { Vec3 } from './vec3.js';
import type { Mat4 } from './mat4.js';
import type { Quat } from './quat.js';