webgl canvas烟花雨动画效果代码-html代码-BFW代码库

webgl canvas烟花雨动画效果代码

代码语言：html

所属分类：动画

代码描述：webgl canvas烟花雨动画效果代码，点击鼠标看效果。

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>
canvas {
	position: absolute;
	top: 0;
	left: 0;
	background-color: #111;
}
</style>



</head>

<body>
  <canvas id=c></canvas>

  
      <script  >
var gl = c.getContext('webgl', { preserveDrawingBuffer: true }),
w = c.width = window.innerWidth,
h = c.height = window.innerHeight,

webgl = {},
opts = {
  projectileAlpha: .8,
  projectileLineWidth: 1.3,
  fireworkAngleSpan: .5,
  baseFireworkVel: 3,
  addedFireworkVel: 3,
  gravity: .03,
  lowVelBoundary: -.2,
  xFriction: .995,
  baseShardVel: 1,
  addedShardVel: .2,
  fireworks: 1000,
  baseShardsParFirework: 10,
  addedShardsParFirework: 10,
  shardFireworkVelMultiplier: .3,
  initHueMultiplier: 1 / 360,
  runHueAdder: .1 / 360 };


webgl.vertexShaderSource = `
uniform int u_mode;
uniform vec2 u_res;
attribute vec4 a_data;
varying vec4 v_color;

vec3 h2rgb( float h ){
	return clamp( abs( mod( h * 6. + vec3( 0, 4, 2 ), 6. ) - 3. ) -1., 0., 1. );
}
void clear(){
	gl_Position = vec4( a_data.xy, 0, 1 );
	v_color = vec4( 0, 0, 0, a_data.w );
}
void draw(){
	gl_Position = vec4( vec2( 1, -1 ) * ( ( a_data.xy / u_res ) * 2. - 1. ), 0, 1 );
	v_color = vec4( h2rgb( a_data.z ), a_data.w );
}
void main(){
	if( u_mode == 0 )
		draw();
	else
		clear();
}
`;
webgl.fragmentShaderSource = `
precision mediump float;
varying vec4 v_color;

void main(){
	gl_FragColor = v_color;
}
`;

webgl.vertexShader = gl.createShader(gl.VERTEX_SHADER);
gl.shaderSource(webgl.vertexShader, webgl.vertexShaderSource);
gl.compileShader(webgl.vertexShader);

webgl.fragmentShader = gl.createShader(gl.FRAGMENT_SHADER);
gl.shaderSource(webgl.fragmentShader, webgl.fragmentShaderSource);
gl.compileShader(webgl.fragmentShader);

webgl.shaderProgram = gl.createProgram();
gl.attachShader(webgl.shaderProgram, webgl.vertexShader);
gl.attachShader(webgl.shaderProgram, webgl.fragmentShader);

gl.linkProgram(webgl.shaderProgram);
gl.useProgram(webgl.shaderProgram);

webgl.dataAttribLoc = gl.getAttribLocation(webgl.shaderProgram, 'a_data');
webgl.dataBuffer = gl.createBuffer();

gl.enableVertexAttribArray(webgl.dataAttribLoc);
gl.bindBuffer(gl.ARRAY_BUFFER, webgl.dataBuffer);
gl.vertexAttribPointer(webgl.dataAttribLoc, 4, gl.FLOAT, false, 0, 0);

webgl.resUniformLoc = gl.getUniformLocation(webgl.shaderProgram, 'u_res');
webgl.modeUniformLoc = gl.getUniformLocation(webgl.shaderProgram, 'u_mode');

gl.viewport(0, 0, w, h);
gl.uniform2f(webgl.resUniformLoc, w, h);

gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA);
gl.enable(gl.BLEND);

gl.lineWidth(opts.projectileLineWidth);

webgl.data = [];

webgl.clear = function () {

  gl.uniform1i(webgl.modeUniformLoc, 1);
  var a = .1;
  webgl.data = [
  -1, -1, 0, a,
  1, -1, 0, a,
  -1, 1, 0, a,
  -1, 1, 0, a,
  1, -1, 0, a,
  1, 1, 0, a];

  webgl.draw(gl.TRIANGLES);
  gl.uniform1i(webgl.modeUniformLoc, 0);
  webgl.data.length = 0;
};
webgl.draw = function (glType) {

  gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(webgl.data), gl.STATIC_DRAW);
  gl.drawArrays(glType, 0, webgl.data.length / 4);
};

var fireworks = [],
tick = 0,
sins = [],
coss = [],
maxShardsParFirework = opts.baseShardsParFirework + opts.addedShardsParFirework,
tau = 6.283185307179586476925286766559;

for (var i = 0; i < maxShardsParFirework; ++i) {
  sins[i] = Ma.........完整代码请登录后点击上方下载按钮下载查看