three实现三维场景字母文字下落地面动画效果代码-html代码-BFW代码库

three实现三维场景字母文字下落地面动画效果代码

代码语言：html

所属分类：三维

代码描述：three实现三维场景字母文字下落地面动画效果代码，无数字母缓慢下落到纸面上排列整齐。

下面为部分代码预览，完整代码请点击下载或在bfwstudio webide中打开

<!DOCTYPE html>
<html lang="en" >

<head>
  <meta charset="UTF-8">
  


  
  
<style>
body{
  overflow: hidden;
  margin: 0;
}
</style>


  
</head>

<body >
  <script type="importmap">
  {
    "imports": {
      "three": "//repo.bfw.wiki/bfwrepo/js/module/three/build/163/three.module.js",
      "three/addons/": "//repo.bfw.wiki/bfwrepo/js/module/three/examples/163/jsm/"
    }
  }
</script>
  
      <script  type="module">
import * as THREE from "three";
import {
  OrbitControls
} from "three/addons/controls/OrbitControls.js";
import * as TWEEN from "three/addons/libs/tween.module.js";
import {
  SimplexNoise
} from "three/addons/math/SimplexNoise.js";

let simplex = new SimplexNoise();

class TextTerrain extends THREE.Object3D {
  constructor(anisotropy) {
    super();
    let alphabet = [..."ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"];
    let textTexture = (() => {
      let c = document.createElement("canvas");
      let ctx = c.getContext("2d");
      let texSize = 2048;
      c.width = texSize;
      c.height = texSize;
      ctx.clearRect(0, 0, texSize, texSize);
      let dim = 8;
      let dimStep = texSize / dim;
      for (let i = 0; i < alphabet.length; i++) {
        //console.log(alphabet.length)
        let tileX = i % 8;
        let tileY = Math.floor(i / 8);
        let x = (tileX + 0.5) * dimStep;
        let y = texSize - (tileY + 0.5) * dimStep;
        //console.log(x, y);
        ctx.fillStyle = `rgba(0, 0, 0, 1)`;
        ctx.textAlign = "center";
        ctx.textBaseline = "middle";
        ctx.font = `bold ${dimStep * 0.9}px Arial`;
        ctx.fillText(alphabet[i], x, y);
      }
      let tex = new THREE.CanvasTexture(c);
      tex.colorSpace = "srgb";
      tex.anisotropy = anisotropy;
      return tex;
    })();


    let tileDim = 200;

    let g = new THREE.PlaneGeometry();
    g.setAttribute("letterIdx", new THREE.InstancedBufferAttribute(new Float32Array(Array.from({
      length: tileDim * tileDim
    }, () => {
      return THREE.MathUtils.randInt(0, alphabet.length - 1)
    })), 1));
    //console.log(g);
    let m = new THREE.MeshBasicMaterial({
      map: textTexture,
      transparent: true,
      alphaTest: 0.01,
      side: THREE.DoubleSide,
      //forceSinglePass: true,
      onBeforeCompile: shader => {
        shader.vertexShader = `
        	attribute float letterIdx;
          varying float vLetterIdx;
        	${shader.vertexShader}
        `.replace(
          `#include <uv_vertex>`,
          `#include <uv_vertex>
          vLetterIdx = letterIdx;
          `
        );
        //console.log(shader.vertexShader);

        shader.fragmentShader = `
        	varying float vLetterIdx;
          ${shader.fragmentShader}
        `.replace(
          `#include <map_fragment>`,
          `
          float letterIdx = floor(vLetterIdx + 0.1);
          float tileStep = 1. / 8.;
          float u = mod(letterIdx, 8.);
          float v = floor(letterIdx / 8.);
          vec2 iUv = (vec2(u, v) + vMapUv) * tileStep;
          vec4 sampledDiffuseColor = texture2D( map, iUv );
					diffuseColor *= sampledDiffuseColor;
          `
        );
        //console.log(shader.fragmentShader);
      }
    });
    let io = new THREE.InstancedMesh(g, m, tileDim * tileDim);
    this.instancedMesh = io;

    this.dummy = new THREE.Object3D();

    this.finals = [];

    let tri = new THREE.Triangle();
    let n = new THREE.Vector3();
    let la = new THREE.Vector3();

    function getY(x, z) {
      return simplex.noise(x * 0.01, z * 0.01) * 7.5;
    }

    let setFinals = () => {
      let y0 = getY(this.dummy.position.x, this.dummy.position.z);
      let y1 = getY(this.dummy.position.x, this.dummy.position.z - 1);
      le.........完整代码请登录后点击上方下载按钮下载查看