前言
前段时间想要做一个web端的图形化积木式编程（类似少儿编程）的案例，网上冲浪了一圈又一圈，终于技术选型好，然后代码一顿敲，终于出来了一个雏形。
TIPS：该案例设计主要参考iRobot Coding,只用做学习用途，侵删。
最终实现效果
最终实现效果
本文实现效果
-
自定义启动界面
自定义启动界面
完整代码
- 自定义启动界面
<template>
<div style="height: 100%;width: 100%;">
<div>
<canvas id="renderCanvas"></canvas>
</div>
</div>
</template>
<script>
import * as BABYLON from 'babylonjs';
import * as BABYLON_MATERAIAL from "babylonjs-materials"
import ammo from "ammo.js";
import utils from "./utils";
//全局变量
var scene = null //场景实例
var engine = null //3d引擎实例
var camera = null //摄像机实例
var plane = null //绿地
var ground = null //网格
var skybox = null //天空盒
var car = null //小车
var cubeParent = null //方块组
var startingPoint = new BABYLON.Vector3(0, 0, 0)//当前点击位置
// 质量 、摩擦系数、反弹系数
const bodyMass = 0.5, bodyFriction = 0.5, bodyRestitution = 0.9;
const groundFriction = 0.8, groundRestitution = 0.5;
async function loadScene() {
//场景初始化，可看文章一
scene = initScene()
//本文内容，自定义启动动画
customLoadingUI()
//加载网络模型，可看文章二
await initRobot()
//可看文章三，监听拖动事件，实现点击拖动模型
dragListening()
//可看文章四，实现碰撞效果
// 1、初始化重力碰撞系统
await initAmmo()
// 2、将地面和小车加入碰撞体
addPhysicEffect()
//3、加入碰撞体方块
initCubes()
//本文内容，关闭启动动画
setTimeout(()=>{
hideLoadingUI()
},1000)
}
function customLoadingUI() {
const url = "http://localhost:8088/static/simulator/"
BABYLON.DefaultLoadingScreen.prototype.displayLoadingUI = function () {
if (document.getElementById("customLoadingScreenDiv")) {
document.getElementById("customLoadingScreenDiv").style.display = "initial";
return;
}
this._loadingDiv = document.createElement("div");
this._loadingDiv.id = "customLoadingScreenDiv";
this._loadingDiv.style.background = "#505781";
this._loadingDiv.style.height = "100%";
this._loadingDiv.style.width = "700px";
this._loadingDiv.style.alignContent = "center";
this._loadingDiv.style.zIndex = "10006"
var img = new Image()
img.src = url + "loading.gif";
img.style.padding = "15%";
img.style.paddingTop = "30%";
this._loadingDiv.appendChild(img);
this._resizeLoadingUI();
window.addEventListener("resize", this._resizeLoadingUI);
document.body.appendChild(this._loadingDiv);
};
engine.displayLoadingUI();
}
function hideLoadingUI(){
engine.hideLoadingUI()
document.getElementById("customLoadingScreenDiv").remove()
}
async function initAmmo() {
const Ammo = await ammo();
console.log("Ammo", Ammo)
//启用y方向重力
scene.enablePhysics(new BABYLON.Vector3(0, -10, 0), new BABYLON.AmmoJSPlugin(true, Ammo));
scene.onReadyObservable.add(function () {
console.log(scene.getPhysicsEngine()._physicsPlugin.bjsAMMO.btDefaultCollisionConfiguration());
console.log(scene.getPhysicsEngine()._physicsPlugin._collisionConfiguration);
console.log(scene.getPhysicsEngine()._physicsPlugin._dispatcher);
console.log(scene.getPhysicsEngine()._physicsPlugin._solver);
console.log(scene.getPhysicsEngine()._physicsPlugin.world);
});
}
function addPhysicEffect() {
//地面启用碰撞体
plane.physicsImpostor = new BABYLON.PhysicsImpostor(plane, BABYLON.PhysicsImpostor.BoxImpostor, {
mass: 0,
restitution: groundRestitution,
friction: groundFriction
}, scene);
//小车启用碰撞体
var robotBody = utils.getMeshFromMeshs(car, "Glass_Plane.006")
console.log('robotBody', robotBody)
var robotSize = utils.getMeshSize(robotBody)
var robotScale = 50
const robotScalingFactor = robotScale / 10;
var physicsRoot = makePhysicsObjects(car, scene, robotScalingFactor, robotSize)
//小车实例
car = physicsRoot
}
function makePhysicsObjects(newMeshes, scene, scaling, size) {
var physicsRoot = new BABYLON.Mesh("robot", scene);
physicsRoot.position.y -= 2
newMeshes.forEach((m) => {
if (m.parent == null) {
physicsRoot.addChild(m)
}
})
// 将所有碰撞体加入physics impostor
physicsRoot.getChildMeshes().forEach((m) => {
m.scaling.x = Math.abs(m.scaling.x)
m.scaling.y = Math.abs(m.scaling.y)
m.scaling.z = Math.abs(m.scaling.z)
// console.log("m.name",m.name)
m.physicsImpostor = new BABYLON.PhysicsImpostor(m, BABYLON.PhysicsImpostor.BoxImpostor, {mass: 0.1}, scene);
})
// 缩放根对象并将其变成physics impostor
physicsRoot.scaling.scaleInPlace(scaling)
physicsRoot.physicsImpostor = new BABYLON.PhysicsImpostor(physicsRoot, BABYLON.PhysicsImpostor.NoImpostor, {
mass: bodyMass,
friction: bodyFriction,
restitution: bodyRestitution
}, scene);
//转为碰撞体后，其y轴会偏移，偏移比例根据实际调整
const impostorOffset = -(size.y) / 1.1
physicsRoot.physicsImpostor.setDeltaPosition(new BABYLON.Vector3(0, impostorOffset, 0));
physicsRoot.position.subtractInPlace(new BABYLON.Vector3(0, -impostorOffset, 0));
return physicsRoot
}
function initCubes() {
var scale = 1
const scalingFactor = scale / 10;
cubeParent = new BABYLON.TransformNode("cubes");
const cubeHeight = 80 * scalingFactor
var cube = createBasicRoundedBox(scene, "cube", cubeHeight)
cube.position._y += cubeHeight / 2
cube.position._x -= 100
cube.material = new BABYLON.StandardMaterial("amaterial", scene);
cube.material.diffuseColor = new BABYLON.Color3(16 / 255.0, 156 / 255.0, 73 / 255.0);
cubeParent[0] = cube
var cube2 = createBasicRoundedBox(scene, "cube2", cubeHeight)
cube2.position._y += cubeHeight / 2
cube2.position._x -= 100
cube2.position._z += cubeHeight * 2
cube2.material = new BABYLON.StandardMaterial("amaterial", scene);
cube2.material.diffuseColor = new BABYLON.Color3(48 / 255.0, 102 / 255.0, 150 / 255.0);
cubeParent[1] = cube2
var cube3 = createBasicRoundedBox(scene, "cube3", cubeHeight)
cube3.position._y += cubeHeight / 2
cube3.position._x -= 100
cube3.position._z -= cubeHeight * 2
cube3.material = new BABYLON.StandardMaterial("amaterial", scene);
cube3.material.diffuseColor = new BABYLON.Color3(199 / 255.0, 88 / 255.0, 93 / 255.0);
cubeParent[2] = cube3
//对象事件监听
let actionManager = new BABYLON.ActionManager(scene);
cube.actionManager = actionManager;
cube2.actionManager = actionManager;
cube3.actionManager = actionManager;
// 方块鼠标hover高亮
var hl = new BABYLON.HighlightLayer("hl1", scene);
actionManager.registerAction(new BABYLON.ExecuteCodeAction(BABYLON.ActionManager.OnPointerOverTrigger, function (evn) {
var hover_cube = evn.meshUnderPointer.id
if (hover_cube == cube.name) {
hl.addMesh(cube, BABYLON.Color3.White());
} else if (hover_cube == cube2.name) {
hl.addMesh(cube2, BABYLON.Color3.White());
} else if (hover_cube == cube3.name) {
hl.addMesh(cube3, BABYLON.Color3.White());
}
}));
//方块鼠标hover离开取消高亮
actionManager.registerAction(new BABYLON.ExecuteCodeAction(BABYLON.ActionManager.OnPointerOutTrigger, function (evn) {
var hover_cube = evn.meshUnderPointer.id
if (hover_cube == cube.name) {
hl.removeMesh(cube);
} else if (hover_cube == cube2.name) {
hl.removeMesh(cube2);
} else if (hover_cube == cube3.name) {
hl.removeMesh(cube3);
}
}));
scene.freezeMaterials();
}
//创建带碰撞体的方块
function createBasicRoundedBox(scene, name, size, mass = 0.25, restitution = 0.5, friction = 0.5) {
const boxSide = size;
const sphereSide = boxSide * 3.1 / 2;
const sphere = BABYLON.MeshBuilder.CreateSphere('sphere', {diameter: sphereSide, segments: 16}, scene);
const box = BABYLON.Mesh.CreateBox('box', boxSide, scene);
const intersection = BABYLON.CSG.FromMesh(box).intersect(BABYLON.CSG.FromMesh(sphere));
sphere.dispose();
box.dispose();
const roundedBox = intersection.toMesh(
name,
new BABYLON.StandardMaterial('roundedBoxMaterial', scene),
scene
);
roundedBox.draggable = true;
roundedBox.physicsImpostor = new BABYLON.PhysicsImpostor(
roundedBox,
BABYLON.PhysicsImpostor.BoxImpostor,
{mass: mass, restitution: restitution, friction: friction}
);
roundedBox.material.freeze();
roundedBox.material.specularColor = new BABYLON.Color3(0, 0, 0);
roundedBox.freezeWorldMatrix()
return roundedBox;
}
//鼠标点击拖动监听
function dragListening() {
// 物体拖拽事件
var canvas = engine.getRenderingCanvas();
var currentMesh;//当前点击的模型网格
//判断当前点击对象是否是地板
var getGroundPosition = function () {
var pickinfo = scene.pick(scene.pointerX, scene.pointerY, function (mesh) {
return (mesh == ground || mesh == plane);
});
if (pickinfo.hit) {
return pickinfo.pickedPoint;
}
return null;
}
//鼠标点下
var onPointerDown = function (evt) {
if (evt.button !== 0) {
return;
}
//判断当前是否点击一个模型网格，如果是地板、天空盒等对象，则设置hit为false
var pickInfo = scene.pick(scene.pointerX, scene.pointerY, function (mesh) {
return (mesh !== ground && mesh !== plane && mesh !== skybox);
});
console.log("pickInfo", pickInfo)
//如果hit为true，则不为地板、天空盒等对象
if (pickInfo.hit) {
currentMesh = pickInfo.pickedMesh;//获取当前点击对象
if (currentMesh.parent == null) {
console.log("no parent")//没有父节点则就是car对象了
} else if (currentMesh.parent.name == car.name) {
//有父节点，证明现在点击的是子对象，而移动需要移动整个小车对象，所以设置当前点击mesh为父节点（即car对象）
currentMesh = currentMesh.parent
}
console.log("currentMesh", currentMesh)
//获取当前移动时地板的坐标
startingPoint = getGroundPosition(evt);
//移动物体时，暂时屏蔽相机的移动控制
if (startingPoint) { // we need to disconnect camera from canvas
setTimeout(function () {
camera.detachControl(canvas);
}, 0);
}
}
}
//鼠标点击着移动中
var onPointerMove = function (evt) {
if (!startingPoint) {
return;
}
if (!currentMesh) {
return;
}
//更新当前点击的地板位置
var current = getGroundPosition(evt);
if (!current) {
return;
}
//更新当前小车坐标位置为点击的地板位置
console.log('startingPoint', startingPoint)
var diff = current.subtract(startingPoint);
console.log('diff', diff)
currentMesh.position.addInPlace(diff);
console.log("currentMesh.name", currentMesh.name)
//更新位置信息
startingPoint = current;
}
//鼠标点击后松开
var onPointerUp = function () {
//恢复相机移动控制
if (startingPoint) {
camera.attachControl(canvas, true);
startingPoint = null;
return;
}
}
//canvas绑定监听事件
canvas.addEventListener("pointerdown", onPointerDown, false);
canvas.addEventListener("pointerup", onPointerUp, false);
canvas.addEventListener("pointermove", onPointerMove, false);
}
async function initRobot() {
console.log('initRobot')
//模型url路径
const url = "http://localhost:8088/static/model/"
//模型名称
const modelName = "sportcar.babylon"
var result = await BABYLON.SceneLoader.ImportMeshAsync(null, url, modelName, scene);
var meshes = result.meshes
console.log("meshes", meshes)
//不直接实例化小车节点，car对象存储meshes网格列表，在小车引入碰撞体后再实例化
car = meshes
}
function initScene() {
//获取到renderCanvas这个元素
var canvas = document.getElementById("renderCanvas");
//初始化引擎
engine = new BABYLON.Engine(canvas, true);
//初始化场景
var scene = new BABYLON.Scene(engine);
//注册一个渲染循环来重复渲染场景
engine.runRenderLoop(function () {
scene.render();
});
//浏览器窗口变化时监听
window.addEventListener("resize", function () {
engine.resize();
});
//相机初始化
camera = new BABYLON.ArcRotateCamera("Camera", 0, 0, 5, new BABYLON.Vector3(0, 0, 10), scene);
camera.setPosition(new BABYLON.Vector3(-50, 50, 50));
//相机角度限制
camera.upperBetaLimit = 1.5;//最大z轴旋转角度差不多45度俯瞰
camera.lowerRadiusLimit = 50;//最小缩小比例
camera.upperRadiusLimit = 1500;//最大放大比例
//变焦速度
camera.wheelPrecision = 1; //电脑滚轮速度 越小灵敏度越高
camera.pinchPrecision = 20; //手机放大缩小速度 越小灵敏度越高
scene.activeCamera.panningSensibility = 100;//右键平移灵敏度
// 将相机和画布关联
camera.attachControl(canvas, true);
//灯光初始化
var light = new BABYLON.HemisphericLight("light1", new BABYLON.Vector3(0, 10, 0), scene);
//设置高光颜色
light.specular = new BABYLON.Color3(0, 0, 0);
//设置灯光强度
light.intensity = 1
// 绿地初始化
var materialPlane = new BABYLON.StandardMaterial("texturePlane", scene);
materialPlane.diffuseColor = new BABYLON.Color3(152 / 255.0, 209 / 255.0, 115 / 255.0)
materialPlane.backFaceCulling = false;
materialPlane.freeze()
plane = BABYLON.MeshBuilder.CreateDisc("ground", {radius: 3000}, scene);
plane.rotation.x = Math.PI / 2;
plane.material = materialPlane;
plane.position.y = -0.1;
plane.freezeWorldMatrix()
//网格地板初始化
const groundSide = 144;
ground = BABYLON.Mesh.CreateGround("ground", groundSide, groundSide, 1, scene, true);
var groundMaterial = new BABYLON_MATERAIAL.GridMaterial("grid", scene);
groundMaterial.mainColor = BABYLON.Color3.White();//底板颜色
groundMaterial.alpha = 1;//透明度
const gridLineGray = 0.95;
groundMaterial.lineColor = new BABYLON.Color3(gridLineGray, gridLineGray, gridLineGray);
groundMaterial.backFaceCulling = true; // 可看到背面
//大网格间距
groundMaterial.majorUnitFrequency = 16;
//小网格间距
groundMaterial.minorUnitVisibility = 0;
const gridOffset = 8; // 网格偏移量
groundMaterial.gridOffset = new BABYLON.Vector3(gridOffset, 0, gridOffset);
groundMaterial.freeze(); // 冻结材质，优化渲染速度
ground.material = groundMaterial
ground.freezeWorldMatrix()
//天空盒初始化
var skyMaterial = new BABYLON_MATERAIAL.SkyMaterial("skyMaterial", scene);
skyMaterial.inclination = 0
skyMaterial.backFaceCulling = false;
skybox = BABYLON.Mesh.CreateBox("skyBox", 5000.0, scene);
skybox.material = skyMaterial;
return scene
}
export default {
name: "test",
data() {
return {}
},
async mounted() {
//加载场景
await loadScene()
},
}
</script>
<style scoped>
#renderCanvas {
width: 680px;
height: 680px;
touch-action: none;
z-index: 10000;
border-radius: 10px;
}
</style>
- utils.js - 公用方法封装
var utils = {
//meshs中根据名称获取mesh
getMeshFromMeshs(newMeshes, name) {
var mesh = null
newMeshes.forEach(m => {
if (m.name == name) {
mesh = m
}
})
return mesh
},
//获取mesh的尺寸信息
getMeshSize(checkmesh) {
const sizes = checkmesh.getHierarchyBoundingVectors()
const size = {
x: (sizes.max.x - sizes.min.x),
y: (sizes.max.y - sizes.min.y),
z: (sizes.max.z - sizes.min.z)
}
return size
},
}
export default utils;
代码分解
本文要实现的功能:
1、自定义启动界面并显示
2、模型资源加载完毕后，移除启动界面
1.自定义启动页面
- BABYLON.DefaultLoadingScreen的原型对象中有一个displayLoadingUI的函数，可以更改默认启动加载界面
需要注意，自定义启动界面需要在引擎engine初始化后再调用
function customLoadingUI() {
const url = "http://localhost:8088/static/simulator/"
BABYLON.DefaultLoadingScreen.prototype.displayLoadingUI = function () {
if (document.getElementById("customLoadingScreenDiv")) {
document.getElementById("customLoadingScreenDiv").style.display = "initial";
return;
}
//创建一个div标签并加入gif动图
this._loadingDiv = document.createElement("div");
this._loadingDiv.id = "customLoadingScreenDiv";
this._loadingDiv.style.background = "#505781";
this._loadingDiv.style.height = "100%";
this._loadingDiv.style.width = "700px";
this._loadingDiv.style.alignContent = "center";
this._loadingDiv.style.zIndex = "10006"
var img = new Image()
img.src = url + "loading.gif";
img.style.padding = "15%";
img.style.paddingTop = "30%";
this._loadingDiv.appendChild(img);
//调用babylonjs的_resizeLoadingUI以重置启动界面，并重新接听reisze
this._resizeLoadingUI();
window.addEventListener("resize", this._resizeLoadingUI);
//将创建的div加入到页面中
document.body.appendChild(this._loadingDiv);
};
//启动加载界面
engine.displayLoadingUI();
}
2.移除启动页面
function hideLoadingUI(){
//引擎隐藏加载界面
engine.hideLoadingUI()
//引擎隐藏加载界面后，div标签并没有销毁，拖动界面时会拖动到gif图层，所以需要移除标签
document.getElementById("customLoadingScreenDiv").remove()
}
后续计划
Babylon.js
- 启动界面镜头动画
- babylonjs-gui 按钮实现
- 将3d界面放入可拖动窗口中
Blockly
- 入门使用blockly
- 自定义block块
- blockly第三方组件使用
- 接入js-interpreter，步骤运行block块
- ......(想到啥写啥)
