webgl/public/gl/core/Entity.js

import { Vec3 } from '../math/Vec3.js'
import { Mat4 } from '../math/Mat4.js'

export class Entity {

    static #id = 0

    constructor(mesh) {
        this.mesh = mesh
        this.position = new Vec3()
        this.rotation = new Vec3()
        this.scale = new Vec3(1, 1, 1)
        this.id = Entity.#id
        Entity.#id++
    }

    tran() {
        this.rotation.x %= 360;
        this.rotation.y %= 360;
        this.rotation.z %= 360;
        
        const tran = new Mat4().identity()
        const d = tran.data

        const c3 = Math.cos(this.rotation.z * (Math.PI / 180))
        const s3 = Math.sin(this.rotation.z * (Math.PI / 180))
        const c2 = Math.cos(this.rotation.x * (Math.PI / 180))
        const s2 = Math.sin(this.rotation.x * (Math.PI / 180))
        const c1 = Math.cos(this.rotation.y * (Math.PI / 180))
        const s1 = Math.sin(this.rotation.y * (Math.PI / 180))

        d[0] = this.scale.x * (c1 * c3 + s1 * s2 * s3);
        d[1] = this.scale.x * (c2 * s3)
        d[2] = this.scale.x * (c1 * s2 * s3 - c3 * s1)
        d[3] = 0

        d[4] = this.scale.y * (c3 * s1 * s2 - c1 * s3)
        d[5] = this.scale.y * (c2 * c3)
        d[6] = this.scale.y * (c1 * c3 * s2 + s1 * s3)
        d[7] = 0

        d[8] = this.scale.z * (c2 * s1)
        d[9] = this.scale.z * (-s2)
        d[10] = this.scale.z * (c1 * c2)
        d[11] = 0

        d[12] = this.position.x
        d[13] = this.position.y
        d[14] = this.position.z
        d[15] = 1
        
        return tran
    }

}