Matrix3.multiply()

Matrix3.multiply() 是three.js中的一个方法，用于计算矩阵乘积并将结果存储在当前矩阵对象上。

语法

matrix3.multiply(matrix)

参数

• matrix：Matrix3 类型的矩阵对象，被用来和当前矩阵对象计算矩阵乘积。

描述

矩阵乘积是将两个矩阵 A 和 B 相乘的运算，结果是一个新矩阵 C。在three.js中，使用 Matrix3.multiply() 方法可以在当前矩阵对象上计算矩阵乘积。

由于three.js内部使用列主序（column-major order）的矩阵来处理变换，因此当把两个矩阵相乘时需要注意操作顺序。在three.js中，矩阵 B 乘以矩阵 A 的运算应该写作 B.multiply(A)，这与常规的数学符号 AB 是相反的。

示例

var A = new THREE.Matrix3().set(
  1, 2, 3,
  4, 5, 6,
  7, 8, 9
);

var B = new THREE.Matrix3().set(
  9, 8, 7,
  6, 5, 4,
  3, 2, 1
);

A.multiply(B);

console.log(A.elements); // [30, 24, 18, 84, 69, 54, 138, 114, 90]

在这个例子中，我们首先创建了两个矩阵 A 和 B，然后将它们相乘并将结果存储在矩阵 A 中。最后，我们输出了矩阵 A 的元素。

Matrix3.multiply()

Matrix3.multiply() is a method in three.js that calculates the matrix product and stores the result in the current matrix object.

Syntax

matrix3.multiply(matrix)

Parameters

• matrix: A Matrix3 object. It is used to compute the matrix product with the current matrix object.

Description

The matrix product is the operation of multiplying two matrices A and B, resulting in a new matrix C. In three.js, the Matrix3.multiply() method is used to calculate the matrix product on the current matrix object.

Since three.js uses matrices in column-major order to handle transformations, it is important to be mindful of the order of operations when multiplying two matrices. In three.js, the operation B multiplied by A is written as B.multiply(A), which is opposite to the typical mathematical notation AB.

Example

var A = new THREE.Matrix3().set(
  1, 2, 3,
  4, 5, 6,
  7, 8, 9
);

var B = new THREE.Matrix3().set(
  9, 8, 7,
  6, 5, 4,
  3, 2, 1
);

A.multiply(B);

console.log(A.elements); // [30, 24, 18, 84, 69, 54, 138, 114, 90]

In this example, we first create two matrices A and B, then multiply them and store the result in matrix A. Finally, we output the elements of matrix A.