webgl实现粒子汇聚成文字动画效果代码-html代码-BFW代码库

webgl实现粒子汇聚成文字动画效果代码

代码语言：html

所属分类：粒子

代码描述：webgl实现粒子汇聚成文字动画效果代码

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 {
    margin: 0; 
    overflow: hidden;
}

a {
    position: fixed;
    display: inline-block;
    margin-left: calc(50vw - 70px);
    font-size:20px;
    z-index:1;
    color: white;
}
</style>



</head>

<body >
  

  
      <script >
let canvas = document.createElement('canvas');
canvas.style.background = '#000';
document.body.appendChild(canvas);
let gl = canvas.getContext("webgl", { preserveDrawingBuffer: true });

let clearPass = program({
  type: gl.TRIANGLES,
  vertexSize: 2,
  vertices: [-1, 3, -1, -1, 3, -1], // full screen triangle
  shaders: [`
            attribute vec2 pt;
            void main(void) {
                gl_Position=vec4(pt, 0.0, 1.0);
            }`, `
            void main(void) {
                gl_FragColor=vec4(0.0, 0.0, 0.0, 0.05);
            }`] });


let particles = program({
  type: gl.POINTS,
  vertexSize: 4,
  vertices: createVertices(),
  uniforms: { time: '1f', resolution: '2f' },
  shaders: [`
            uniform float time;
            uniform vec2 resolution;
            attribute vec4 pt;
            varying float i;
            void main() {
                float aspect = resolution.y/resolution.x;
                float t = smoothstep(0.0, 1.0, fract(time*0.3));
                t += mod(floor(time*0.3), 2.0);
                t *= 3.1415;
                i = fract(pt.x*pt.y*pt.z*pt.w);
                vec2 c = (pt.xy + pt.zw)/2.0;
                float a = atan(pt.y - c.y, pt.x - c.x);
                float r = length(vec2(pt.x - c.x, pt.y - c.y));
                r -= sin(t*3.)*0.005; 
                c += vec2(cos(a+t), sin(a+t)) * r;
                gl_Position = vec4(c.x*aspect, c.y, 0., 1.);
                gl_PointSize = 10.0;
            }`, `
            uniform float time;
            varying float i;
            float ch(vec2 uv) {
                float d = length(uv - 0.5);
                return smoothstep(0.2, 0.00, d);
            }
            void main() {
                float d = length(gl_PointCoord.xy-0.5);
                d = smoothstep(0.5, 0.00, d);
                gl_FragColor = vec4(
                    ch(gl_PointCoord.xy-0.25*sin(time+i)),
                    ch(gl_PointCoord.xy),
                    ch(gl_PointCoord.xy+0.25*sin(time+i)), 
                    0.01
                 );
            }`] });


gl.enable(gl.BLEND);

requestAnimationFrame(function draw(t) {

  gl.blendFunc(gl.ONE, gl.ONE); // additive
  particles.bind();
  if (canvas.width != innerWidth || canvas.height !== innerHeight) {
    particles.uniforms.resolution([innerWidth, innerHeight]);
    g.........完整代码请登录后点击上方下载按钮下载查看