js+webgl实现三维气旋龙卷风动画效果代码-html代码-BFW代码库

代码语言：html

所属分类：三维

代码描述：js+webgl实现三维气旋龙卷风动画效果代码粒子烟花绽放动画效果代码

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 {
  background: #333;
  color: #fff;
  font-family: sans-serif;
}
body,
html {
  margin: 0;
  overflow: hidden;
  padding: 0;
}
canvas { width:100%; height: 100%; }
</style>

  
  
</head>

<body translate="no">
  <script type="text/fragment" id="fragShader">#version 300 es
  precision highp float;
  
  uniform vec2 u_resolution;
  uniform float u_time;
  uniform vec2 u_mouse;
  uniform sampler2D s_noise;
  uniform vec3 u_cp;
  
  in vec2 v_uv;
  out vec4 c;
  
  /* Shading constants */
  /* --------------------- */
  const vec3 LP = vec3(-0.6, 0.7, -0.3);  // light position
  const vec3 LC = vec3(.85,0.80,0.70);    // light colour
  const vec3 HC1 = vec3(.5, .4, .3);      // hemisphere light colour 1
  const vec3 HC2 = vec3(0.1,.1,.6)*.5;    // hemisphere light colour 2
  const vec3 HLD = vec3(0,1,0)*.5+.5;     // hemisphere light direction
  const vec3 BC = vec3(0.25,0.25,0.25);   // back light colour
  const vec3 FC = vec3(1.30,1.20,1.00);   // fresnel colour
  const float AS = .5;                     // ambient light strength
  const float DS = 1.;                     // diffuse light strength
  const float BS = .3;                     // back light strength
  const float FS = .3;                     // fresnel strength
  /* Raymarching constants */
  /* --------------------- */
  const float MAX_TRACE_DISTANCE = 10.;             // max trace distance
  const float INTERSECTION_PRECISION = 0.001;       // precision of the intersection
  const int NUM_OF_TRACE_STEPS = 256;               // max number of trace steps
  const float STEP_MULTIPLIER = .5;                 // the step mutliplier - ie, how much further to progress on each step
  
  /* Structures */
  /* ---------- */
  struct Camera {
    vec3 ro;
    vec3 rd;
    vec3 forward;
    vec3 right;
    vec3 up;
    float FOV;
  };
  struct Surface {
    float len;
    vec3 position;
    vec3 colour;
    float id;
    float steps;
    float AO;
  };
  struct Model {
    float dist;
    vec3 colour;
    float id;
  };
  
  /* Utilities */
  /* ---------- */
  vec2 toScreenspace(in vec2 p) {
    vec2 uv = (p - 0.5 * u_resolution.xy) / min(u_resolution.y, u_resolution.x);
    return uv;
  }
  mat2 R(float a) {
    float c = cos(a);
    float s = sin(a);
    return mat2(c, -s, s, c);
  }
  Camera getCamera(in vec2 uv, in vec3 pos, in vec3 target) {
    vec3 f = normalize(target - pos);
    vec3 r = normalize(vec3(f.z, 0., -f.x));
    vec3 u = normalize(cross(f, r));
    
    float FOV = .6;
    
    return Camera(
      pos,
      normalize(f + FOV * uv.x * r + FOV * uv.y * u),
      f,
      r,
      u,
      FOV
    );
  }
  
  //	Simplex 3D Noise 
//	by Ian McEwan, Ashima Arts
//
vec4 permute(vec4 x){return mod(((x*34.0)+1.0)*x, 289.0);}
vec4 taylorInvSqrt(vec4 r){return 1.79284291400159 - 0.85373472095314 * r;}
float snoise(vec3 v){ 
  const vec2  C = vec2(1.0/6.0, 1.0/3.0) ;
  const vec4  D = vec4(0.0, 0.5, 1.0, 2.0);

  vec3 i  = floor(v + dot(v, C.yyy) );
  vec3 x0 =   v - i + dot(i, C.xxx) ;

  vec3 g = step(x0.yzx, x0.xyz);
  vec3 l = 1.0 - g;
  vec3 i1 = min( g.xyz, l.zxy );
  vec3 i2 = max( g.xyz, l.zxy );

  vec3 x1 = x0 - i1 + 1.0 * C.xxx;
  vec3 x2 = x0 - i2 + 2.0 * C.xxx;
  vec3 x3 = x0 - 1. + 3.0 * C.xxx;

  i = mod(i, 289.0 ); 
  vec4 p = permute( permute( permute( 
             i.z + vec4(0.0, i1.z, i2.z, 1.0 ))
           + i.y + vec4(0.0, i1.y, i2.y, 1.0 )) 
           + i.x + vec4(0.0, i1.x, i2.x, 1.0 ));

  float n_ = 1.0/7.0; // N=7
  vec3  ns = n_ * D.wyz - D.xzx;

  vec4 j = p - 49.0 * floor(p * ns.z *ns.z);  //  mod(p,N*N)

  vec4 x_ = floor(j * ns.z);
  vec4 y_ = floor(j - 7.0 * x_ );    // mod(j,N)

  vec4 x = x_ *ns.x + ns.yyyy;
  vec4 y = y_ *ns.x + ns.yyyy;
  vec4 h = 1.0 - abs(x) - abs(y);

  vec4 b0 = vec4( x.xy, y.xy );
  vec4 b1 = vec4( x.zw, y.zw );

  vec4 s0 = floor(b0)*2.0 + 1.0;
  vec4 s1 = floor(b1)*2.0 + 1.0;
  vec4 sh = -step(h, vec4(0.0));

  vec4 a0 = b0.xzyw + s0.xzyw*sh.xxyy ;
  vec4 a1 = b1.xzyw + s1.xzyw*sh.zzww ;

  vec3 p0 = vec3(a0.xy,h.x);
  vec3 p1 = vec3(a0.zw,h.y);
  vec3 p2 = vec3(a1.xy,h.z);
  vec3 p3 = vec3(a1.zw,h.w);

  vec4 norm = taylorInvSqrt(vec4(dot(p0,p0), dot(p1,p1), dot(p2, p2), dot(p3,p3)));
  p0 *= norm.x;
  p1 *= norm.y;
  p2 *= norm.z;
  p3 *= norm.w;

  vec4 m = max(0.6 - vec4(dot(x0,x0), dot(x1,x1), dot(x2,x2), dot(x3,x3)), 0.0);
  m = m * m;
  return 42.0 * dot( m*m, vec4( dot(p0,x0), dot(p1,x1), 
                                dot(p2,x2), dot(p3,x3) ) );
}
  
  //--------------------------------
  // Modelling
  //--------------------------------
  Model model(vec3 p) {
    float l=length(p.xz), a=atan(p.z,p.x), t=u_time*10., y=p.y*p.y;
    float n = snoise(vec3(l+t,cos(a+p.y*5.-t),p.y));
    n+=snoise(vec3(l*.2,sin(a+p.y*2.),cos(p.y*.2)));
    float d = length(p.xz)-.2-n*.1-y;
    vec3 colour = vec3(.8,.3,.6);
    return Model(d, colour, 1.);
  }
  Model map( vec3 p ){
    return model(p);
  }
  
  /* Modelling utilities */
  /* ---------- */
  // Calculates the normal by taking a very small distance,
  // remapping the function, an.........完整代码请登录后点击上方下载按钮下载查看