web实践学习2

20201303张奕博 2023.1.25

创建浮岛
如以下 👇 两幅图所示,整个浮岛造型是一个四棱椎,整体分为四部分,顶部是由地面和河流构成的四方体、底部三块是倒置的三角。生成这些三维模型的其实也并没有多少技巧,就像搭积木一样使用 Three.js 提供的立方体网格通过计算拼接到一起即可。类 Island 包含一个方法 generate 用于创建上述三维模型,并将所创建模型添加到三维分组 floorMesh 中用于外部调用,其中棱柱部分是通过 CylinderBufferGeometry 来实现的。

export default class Island {
constructor() {
this.floorMesh = new THREE.Group();
this.generate();
}

generate() {
// 左侧地面
const leftFieldMat = new THREE.MeshToonMaterial({
color: 0x015521d,
side: THREE.DoubleSide,
});
const leftFieldGeom = new THREE.BoxBufferGeometry(800, 30, 1800);
this.leftFieldMesh = new THREE.Mesh(leftFieldGeom, leftFieldMat);
// 右侧地面
this.rightFieldMesh = this.leftFieldMesh.clone();
const mapCapMat = new THREE.MeshMatcapMaterial({
matcap: new THREE.TextureLoader().load('./images/matcap.png'),
side: THREE.DoubleSide
})
// 顶部棱柱
const topFieldGeom = new THREE.CylinderBufferGeometry(1200, 900, 200, 4, 4);
this.topFieldMesh = new THREE.Mesh(topFieldGeom, mapCapMat);
// 中间棱柱
const middleFieldGeom = new THREE.CylinderBufferGeometry(850, 600, 200, 4, 4);
this.middleFieldMesh = new THREE.Mesh(middleFieldGeom, mapCapMat);
// 底部棱锥
const bottomFieldGeom = new THREE.ConeBufferGeometry(550, 400, 4);
this.bottomFieldMesh = new THREE.Mesh(bottomFieldGeom, mapCapMat);
// 河面
const strGroundMat = new THREE.MeshLambertMaterial({
color: 0x75bd2d,
side: THREE.DoubleSide,
});
const strCroundGeom = new THREE.BoxBufferGeometry(205, 10, 1800);
this.strGroundMesh = new THREE.Mesh(strCroundGeom, strGroundMat);

// 小河
const streamMat = new THREE.MeshLambertMaterial({
  color: 0x0941ba,
  side: THREE.DoubleSide,
});
const streamGeom = new THREE.BoxBufferGeometry(200, 16, 1800);
this.streamMesh = new THREE.Mesh(streamGeom, streamMat);
// ...

}
};
浮岛俯视图是一个正方形。

浮岛侧视图是一个倒三角形。

创建水流
接下来,我们为河流添加一个小瀑布,使场景动起来。流动的瀑布三维水滴 💧 滴落效果的是通过创建多个限定范围内随机位置的 THREE.BoxBufferGeometry 来实现水滴模型,然后通过水滴的显示隐藏动画实现视觉上的水滴坠落效果。Waterfall 类用于创建单个水滴,它为水滴初始化随机位置和速度,并提供一个 update 方法用来更新它们。

export default class Waterfall {
constructor (scene) {
this.scene = scene;
this.drop = null;
this.generate();
}
generate () {
this.geometry = new THREE.BoxBufferGeometry(15, 50, 5);
this.material = new THREE.MeshLambertMaterial({ color: 0x0941ba });
this.drop = new THREE.Mesh(this.geometry, this.material);
this.drop.position.set((Math.random() - 0.5) * 200, -50, 900 + Math.random(1, 50) * 10);
this.scene.add(this.drop);
this.speed = 0;
this.lifespan = Math.random() * 50 + 50;
this.update = function() {
this.speed += 0.07;
this.lifespan--;
this.drop.position.x += (5 - this.drop.position.x) / 70;
this.drop.position.y -= this.speed;
};
}
};
完成水滴创建后,不要忘了需要在页面重绘动画 tick 方法中像这样更新已创建的水滴数组 drops,使其看起来生成向下流动坠落的效果。

for (var i = 0; i < drops.length; i++) {
drops[i].update();
if (drops[i].lifespan < 0) {
scene.remove(scene.getObjectById(drops[i].drop.id));
drops.splice(i, 1);
}
}

创建桥
在河流上方添加一个小木桥 🌉,这样小兔子就可以通过木桥在小河两边移动了。 类 Bridge 通过 generate 方法创建一个小木桥,并通过三维模型组 bridgeMesh 将其导出,我们可以在上面创建的 Island 类中使用它,将其添加到三维场景中。

export default class Bridge {
constructor() {
this.bridgeMesh = new THREE.Group();
this.generate();
}
generate() {
var woodMat = new THREE.MeshLambertMaterial({
color: 0x543b14,
side: THREE.DoubleSide
});
// 木头
for (var i = 0; i < 15; i++) {
var blockGeom = new THREE.BoxBufferGeometry(10, 3, 70);
var block = new THREE.Mesh(blockGeom, woodMat);
this.bridgeMesh.add(block);
}
// 桥尾
var geometry_rail_v = new THREE.BoxBufferGeometry(3, 20, 3);
var rail_1 = new THREE.Mesh(geometry_rail_v, woodMat);
var rail_2 = new THREE.Mesh(geometry_rail_v, woodMat);
var rail_3 = new THREE.Mesh(geometry_rail_v, woodMat);
var rail_4 = new THREE.Mesh(geometry_rail_v, woodMat);
// ...
}
}

创建树
从预览动图和页面可以看到,浮岛上共有两种树 🌳,绿色的高树和粉红色的矮树,树的实现也非常简单,是使用了两个 BoxBufferGeometry 拼接到一起。类 Tree 和 LeafTree 分别用于生成这两种树木,接收参数 (x, y, z) 分别表示树木在场景中的位置信息。我们可以在 Island 辅导上添加一些树木,构成浮岛上的一片小森林。

export default class Tree {
constructor(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
this.treeMesh = new THREE.Group();
this.generate();
}
generate() {
// 树干
var trunkMat = new THREE.MeshLambertMaterial({
color: 0x543b14,
side: THREE.DoubleSide
});
var trunkGeom = new THREE.BoxBufferGeometry(20, 200, 20);
this.trunkMesh = new THREE.Mesh(trunkGeom, trunkMat);
// 树叶
var leavesMat = new THREE.MeshLambertMaterial({
color: 0x016316,
side: THREE.DoubleSide
});
var leavesGeom = new THREE.BoxBufferGeometry(80, 400, 80);
this.leavesMesh = new THREE.Mesh(leavesGeom, leavesMat);
this.treeMesh.add(this.trunkMesh);
this.treeMesh.add(this.leavesMesh);
this.treeMesh.position.set(this.x, this.y, this.z);
// ...
}
}
矮树

export default class LeafTree {
constructor(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
this.treeMesh = new THREE.Group();
this.generate();
}
generate() {
// ...
}
}

创建胡萝卜
接着,在地面上添加一些胡萝卜 🥕。胡萝卜身体部分是通过四棱柱 CylinderBufferGeometry 实现的,然后通过 BoxBufferGeometry 立方体来实现胡萝卜的两片叶子。场景中可以通过 Carrot 类来添加胡萝卜,本页面示例中是通过循环调用添加了 20 个随机位置的胡萝卜。

export default class Carrot {
constructor() {
this.carrotMesh = new THREE.Group();
this.generate();
}
generate() {
const carrotMat = new THREE.MeshLambertMaterial({
color: 0xd9721e
});
const leafMat = new THREE.MeshLambertMaterial({
color: 0x339e33
});
// 身体
const bodyGeom = new THREE.CylinderBufferGeometry(5, 3, 12, 4, 1);
this.body = new THREE.Mesh(bodyGeom, carrotMat);
// 叶子
const leafGeom = new THREE.BoxBufferGeometry(5, 10, 1, 1);
this.leaf1 = new THREE.Mesh(leafGeom, leafMat);
this.leaf2 = this.leaf1.clone();
// ...
this.carrotMesh.add(this.body);
this.carrotMesh.add(this.leaf1);
this.carrotMesh.add(this.leaf2);
}
};
for (let i = 0; i < 20; i++) {
carrot[i] = new Carrot();
scene.add(carrot[i].carrotMesh);
carrot[i].carrotMesh.position.set(-170 * Math.random() * 3 - 300, -12, 1400 * Math.random() * 1.2 - 900);
}

创建兔子
最后,来创建页面的主角兔子 🐇。兔子全部都是由立方体 BoxBufferGeometry 搭建而成的,整体可以分解为头、眼睛、耳朵、鼻子、嘴、胡须、身体、尾巴、四肢等构成,构建兔子时的核心要素就是各个立方体位置和缩放比例的调整,需要具备一定的审美能力,当然本例中使用的兔子是在 Three.js 社区开源代码的基础上改造的 😂。

完成兔子的整体外形之后,我们通过 gsap 给兔子添加一些运动动画效果和方法以供外部调用,其中 blink() 方法用于眨眼、jump() 方法用于原地跳跃、nod() 方法用于点头、run() 方法用于奔跑、fall() 方法用于边界检测时检测到超出运动范围时使兔子坠落效果等。完成 Rabbit 类后,我们就可以在场景中初始化小兔子。

import { TweenMax, Power0, Power1, Power4, Elastic, Back } from 'gsap';

export default class Rabbit {
constructor() {
this.bodyInitPositions = [];
this.runningCycle = 0;
this.rabbitMesh = new THREE.Group();
this.bodyMesh = new THREE.Group();
this.headMesh = new THREE.Group();
this.generate();
}
generate() {
var bodyMat = new THREE.MeshLambertMaterial({
color: 0x5c6363
});
var tailMat = new THREE.MeshLambertMaterial({
color: 0xc2bebe
});
var nouseMat = new THREE.MeshLambertMaterial({
color: 0xed716d
});
// ...
var pawMat = new THREE.MeshLambertMaterial({
color: 0xbf6970
});
var bodyGeom = new THREE.BoxBufferGeometry(50, 50, 42, 1);
var headGeom = new THREE.BoxBufferGeometry(44, 44, 54, 1);
var earGeom = new THREE.BoxBufferGeometry(5, 60, 10, 1);
var eyeGeom = new THREE.BoxBufferGeometry(20, 20, 8, 1);
var irisGeom = new THREE.BoxBufferGeometry(8, 8, 8, 1);
var mouthGeom = new THREE.BoxBufferGeometry(8, 16, 4, 1);
var mustacheGeom = new THREE.BoxBufferGeometry(0.5, 1, 22, 1);
var spotGeom = new THREE.BoxBufferGeometry(1, 1, 1, 1);
var legGeom = new THREE.BoxBufferGeometry(33, 33, 10, 1);
var pawGeom = new THREE.BoxBufferGeometry(45, 10, 10, 1);
var pawFGeom = new THREE.BoxBufferGeometry(20, 20, 20, 1);
var tailGeom = new THREE.BoxBufferGeometry(20, 20, 20, 1);
var nouseGeom = new THREE.BoxBufferGeometry(20, 20, 15, 1);
var tailGeom = new THREE.BoxBufferGeometry(23, 23, 23, 1);
this.body = new THREE.Mesh(bodyGeom, bodyMat);
this.bodyMesh.add(this.body);
this.head = new THREE.Mesh(headGeom, bodyMat);
this.bodyMesh.add(this.legL);
this.headMesh.add(this.earR);
this.rabbitMesh.add(this.bodyMesh);
this.rabbitMesh.add(this.headMesh);
// ...
}
blink() {
var sp = 0.5 + Math.random();
if (Math.random() > 0.2)
TweenMax.to([this.eyeR.scale, this.eyeL.scale], sp / 8, {
y: 0,
ease: Power1.easeInOut,
yoyo: true,
repeat: 3
});
}
// 跳跃
jump() {
var speed = 10;
var totalSpeed = 10 / speed;
var jumpHeight = 150;
TweenMax.to(this.earL.rotation, totalSpeed / 2, {
z: "+=.3",
ease: Back.easeOut,
yoyo: true,
repeat: 1
});
TweenMax.to(this.earR.rotation, totalSpeed / 2, {
z: "-=.3",
ease: Back.easeOut,
yoyo: true,
repeat: 1
});
// ...
}
// 点头
nod() {}
// 奔跑
run() {}
// 移动
move() {}
// 坠落
fall() {}
// 动作销毁
killNod() {}
killJump() {}
killMove() {}
}

posted @ 2023-01-24 18:07  20201303张奕博  阅读(26)  评论(0编辑  收藏  举报