/*
"Fluid" Intro  (c) MoNsTeR, Apr 1997
ByteFall 1997 
http://www.pouet.net/prod.php?which=17407
*/


#ifdef GL_ES
precision mediump float;
#endif

uniform float time;
uniform vec2 mouse;
uniform vec2 resolution;

const float n = 5.;
float r_ = .075;
float t_ = time*1.5;
float rot = time*0.1;
float pi = 3.14159265;
vec3 col;
vec2 dz;
vec2 u = gl_FragCoord.xy - resolution.xy/2.;  
float i=0.;
for(float j=0.; j<n; j++)
  {
  dz = r_ * vec2(cos(j*2.*pi/n - rot), sin(j*2.*pi/n - rot));
  i += sin(t_ + dot(u,dz));
  }
col = cos(vec3(0.,2.*pi,4.*pi)/3.+i*2.)*.5+.5;
gl_FragColor = vec4(col,1.);