js实现3D粒子酷炫动态旋转特效

这篇文章主要为大家详细介绍了js实现3D粒子酷炫动态旋转特效，文中示例代码介绍的非常详细，具有一定的参考价值，感兴趣的小伙伴们可以参考一下

js实现3D粒子酷炫动态旋转特效（效果比较酷炫，中途不仅有形态的变换，还有颜色的变化，希望大家能够喜欢）

代码实现过程中的静态截图

 
 
 
 
 
 
 
 html,body{
 margin:0px;
 width:100%;
 height:100%;
 overflow:hidden;
 background:#000;
}

#canvas{
 position:absolute;
 width:100%;
 height:100%;
}

 
 
 
 function project3D(x,y,z,vars){

 var p,d;
 x-=vars.camX;
 y-=vars.camY-8;
 z-=vars.camZ;
 p=Math.atan2(x,z);
 d=Math.sqrt(x*x+z*z);
 x=Math.sin(p-vars.yaw)*d;
 z=Math.cos(p-vars.yaw)*d;
 p=Math.atan2(y,z);
 d=Math.sqrt(y*y+z*z);
 y=Math.sin(p-vars.pitch)*d;
 z=Math.cos(p-vars.pitch)*d;
 var rx1=-1000;
 var ry1=1;
 var rx2=1000;
 var ry2=1;
 var rx3=0;
 var ry3=0;
 var rx4=x;
 var ry4=z;
 var uc=(ry4-ry3)*(rx2-rx1)-(rx4-rx3)*(ry2-ry1);
 var ua=((rx4-rx3)*(ry1-ry3)-(ry4-ry3)*(rx1-rx3))/uc;
 var ub=((rx2-rx1)*(ry1-ry3)-(ry2-ry1)*(rx1-rx3))/uc;
 if(!z)z=0.000000001;
 if(ua>0&&ua0&&ub<1){
 return {
 x:vars.cx+(rx1+ua*(rx2-rx1))*vars.scale,
 y:vars.cy+y/z*vars.scale,
 d:(x*x+y*y+z*z)
 };
 }else{
 return { d:-1 };
 }
}

function elevation(x,y,z){

 var dist = Math.sqrt(x*x+y*y+z*z);
 if(dist && z/dist>=-1 && z/dist <=1) return Math.acos(z / dist);
 return 0.00000001;
}

function rgb(col){

 col += 0.000001;
 var r = parseInt((0.5+Math.sin(col)*0.5)*16);
 var g = parseInt((0.5+Math.cos(col)*0.5)*16);
 var b = parseInt((0.5-Math.sin(col)*0.5)*16);
 return “#”+r.toString(16)+g.toString(16)+b.toString(16);
}

function interpolateColors(RGB1,RGB2,degree){
 
 var w2=degree;
 var w1=1-w2;
 return [w1*RGB1[0]+w2*RGB2[0],w1*RGB1[1]+w2*RGB2[1],w1*RGB1[2]+w2*RGB2[2]];
}

function rgbArray(col){

 col += 0.000001;
 var r = parseInt((0.5+Math.sin(col)*0.5)*256);
 var g = parseInt((0.5+Math.cos(col)*0.5)*256);
 var b = parseInt((0.5-Math.sin(col)*0.5)*256);
 return [r, g, b];
}

function colorString(arr){

 var r = parseInt(arr[0]);
 var g = parseInt(arr[1]);
 var b = parseInt(arr[2]);
 return “#”+(“0” + r.toString(16) ).slice (-2)+(“0” + g.toString(16) ).slice (-2)+(“0” + b.toString(16) ).slice (-2);
}

function process(vars){

 if(vars.points.length<vars.initParticles) for(var i=0;i<5;++i) spawnParticle(vars);
 var p,d,t;
 
 p = Math.atan2(vars.camX, vars.camZ);
 d = Math.sqrt(vars.camX * vars.camX + vars.camZ * vars.camZ);
 d -= Math.sin(vars.frameNo / 80) / 25;
 t = Math.cos(vars.frameNo / 300) / 165;
 vars.camX = Math.sin(p + t) * d;
 vars.camZ = Math.cos(p + t) * d;
 vars.camY = -Math.sin(vars.frameNo / 220) * 15;
 vars.yaw = Math.PI + p + t;
 vars.pitch = elevation(vars.camX, vars.camZ, vars.camY) – Math.PI / 2;
 
 var t;
 for(var i=0;i<vars.points.length;++i){
 
 x=vars.points[i].x;
 y=vars.points[i].y;
 z=vars.points[i].z;
 d=Math.sqrt(x*x+z*z)/1.0075;
 t=.1/(1+d*d/5);
 p=Math.atan2(x,z)+t;
 vars.points[i].x=Math.sin(p)*d;
 vars.points[i].z=Math.cos(p)*d;
 vars.points[i].y+=vars.points[i].vy*t*((Math.sqrt(vars.distributionRadius)-d)*2);
 if(vars.points[i].y>vars.vortexHeight/2 || d<.25){
 vars.points.splice(i,1);
 spawnParticle(vars);
 }
 }
}

function drawFloor(vars){
 
 var x,y,z,d,point,a;
 for (var i = -25; i <= 25; i += 1) {
 for (var j = -25; j <= 25; j += 1) {
 x = i*2;
 z = j*2;
 y = vars.floor;
 d = Math.sqrt(x * x + z * z);
 point = project3D(x, y-d*d/85, z, vars);
 if (point.d != -1) {
 size = 1 + 15000 / (1 + point.d);
 a = 0.15 – Math.pow(d / 50, 4) * 0.15;
 if (a > 0) {
  vars.ctx.fillStyle = colorString(interpolateColors(rgbArray(d/26-vars.frameNo/40),[0,128,32],.5+Math.sin(d/6-vars.frameNo/8)/2));
  vars.ctx.globalAlpha = a;
  vars.ctx.fillRect(point.x-size/2,point.y-size/2,size,size);
 }
 }
 }
 }
 vars.ctx.fillStyle = “#82f”;
 for (var i = -25; i <= 25; i += 1) {
 for (var j = -25; j <= 25; j += 1) {
 x = i*2;
 z = j*2;
 y = -vars.floor;
 d = Math.sqrt(x * x + z * z);
 point = project3D(x, y+d*d/85, z, vars);
 if (point.d != -1) {
 size = 1 + 15000 / (1 + point.d);
 a = 0.15 – Math.pow(d / 50, 4) * 0.15;
 if (a > 0) {
  vars.ctx.fillStyle = colorString(interpolateColors(rgbArray(-d/26-vars.frameNo/40),[32,0,128],.5+Math.sin(-d/6-vars.frameNo/8)/2));
  vars.ctx.globalAlpha = a;
  vars.ctx.fillRect(point.x-size/2,point.y-size/2,size,size);
 }
 }
 }
 }
}

function sortFunction(a,b){
 return b.dist-a.dist;
}

function draw(vars){

 vars.ctx.globalAlpha=.15;
 vars.ctx.fillStyle=”#000″;
 vars.ctx.fillRect(0, 0, canvas.width, canvas.height);
 
 drawFloor(vars);
 
 var point,x,y,z,a;
 for(var i=0;i<vars.points.length;++i){
 x=vars.points[i].x;
 y=vars.points[i].y;
 z=vars.points[i].z;
 point=project3D(x,y,z,vars);
 if(point.d != -1){
 vars.points[i].dist=point.d;
 size=1+vars.points[i].radius/(1+point.d);
 d=Math.abs(vars.points[i].y);
 a = .8 – Math.pow(d / (vars.vortexHeight/2), 1000) * .8;
 vars.ctx.globalAlpha=a>=0&&a<=1?a:0;
 vars.ctx.fillStyle=rgb(vars.points[i].color);
 if(point.x>-1&&point.x-1&&point.y<vars.canvas.height)vars.ctx.fillRect(point.x-size/2,point.y-size/2,size,size);
 }
 }
 vars.points.sort(sortFunction);
}

function spawnParticle(vars){

 var p,ls;
 pt={};
 p=Math.PI*2*Math.random();
 ls=Math.sqrt(Math.random()*vars.distributionRadius);
 pt.x=Math.sin(p)*ls;
 pt.y=-vars.vortexHeight/2;
 pt.vy=vars.initV/20+Math.random()*vars.initV;
 pt.z=Math.cos(p)*ls;
 pt.radius=200+800*Math.random();
 pt.color=pt.radius/1000+vars.frameNo/250;
 vars.points.push(pt);
}

function frame(vars) {

 if(vars === undefined){
 var vars={};
 vars.canvas = document.querySelector(“canvas”);
 vars.ctx = vars.canvas.getContext(“2d”);
 vars.canvas.width = document.body.clientWidth;
 vars.canvas.height = document.body.clientHeight;
 window.addEventListener(“resize”, function(){
 vars.canvas.width = document.body.clientWidth;
 vars.canvas.height = document.body.clientHeight;
 vars.cx=vars.canvas.width/2;
 vars.cy=vars.canvas.height/2;
 }, true);
 vars.frameNo=0;

 vars.camX = 0;
 vars.camY = 0;
 vars.camZ = -14;
 vars.pitch = elevation(vars.camX, vars.camZ, vars.camY) – Math.PI / 2;
 vars.yaw = 0;
 vars.cx=vars.canvas.width/2;
 vars.cy=vars.canvas.height/2;
 vars.bounding=10;
 vars.scale=500;
 vars.floor=26.5;

 vars.points=[];
 vars.initParticles=2000;
 vars.initV=.01;
 vars.distributionRadius=800;
 vars.vortexHeight=25;
 }

 vars.frameNo++;
 requestAnimationFrame(function() {
 frame(vars);
 });

 process(vars);
 draw(vars);
}
frame();

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。

来源：脚本之家

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