<!-- For @sableRaph's weekly creative coding challenge (https://twitter.com/sableRaph) #WCCChallenge.

 The theme this week was 'Obscure.'

Come join the discord https://discord.gg/5nQDqKGuY4

IDK, im obscuring a picture of the most obscure bird I could find wirh a shader built around a pic of the least obscure bird. 

Obscure buddy is a SOUTH PHILIPPINE DWARF KINGFISHER. 


-->


<div id="shader"></div>
<script id="vertex" type="x-shader/x-vertex">
  varying vec2 vUv;
	void main() { gl_Position = vec4(position, 1.0);
               vUv = uv;
              }
</script>

<script id="fragment" type="x-shader/x-fragment">
precision highp float;

uniform vec2 u_resolution;
uniform float u_time;
  varying vec2 vUv;
  
    uniform sampler2D uTexture;

 
const float PI = 3.1415926535897932384626433832795;
const float TAU = PI * 2.;
const float HALF_PI = PI * .5;
  


void coswarp(inout vec3 trip, float warpsScale ){

  trip.xyz += warpsScale * .1 * cos(3. * trip.yzx + (u_time * .25));
  trip.xyz += warpsScale * .05 * cos(11. * trip.yzx + (u_time * .25));
  trip.xyz += warpsScale * .025 * cos(17. * trip.yzx + (u_time * .25));
  
}

  
 //	Classic Perlin 2D Noise
//	by Stefan Gustavson
//
vec4 permute(vec4 x)
{
    return mod(((x*34.0)+1.0)*x, 289.0);
}


vec2 fade(vec2 t) {return t*t*t*(t*(t*6.0-15.0)+10.0);}

float cnoise(vec2 P){
  vec4 Pi = floor(P.xyxy) + vec4(0.0, 0.0, 1.0, 1.0);
  vec4 Pf = fract(P.xyxy) - vec4(0.0, 0.0, 1.0, 1.0);
  Pi = mod(Pi, 289.0); // To avoid truncation effects in permutation
  vec4 ix = Pi.xzxz;
  vec4 iy = Pi.yyww;
  vec4 fx = Pf.xzxz;
  vec4 fy = Pf.yyww;
  vec4 i = permute(permute(ix) + iy);
  vec4 gx = 2.0 * fract(i * 0.0243902439) - 1.0; // 1/41 = 0.024...
  vec4 gy = abs(gx) - 0.5;
  vec4 tx = floor(gx + 0.5);
  gx = gx - tx;
  vec2 g00 = vec2(gx.x,gy.x);
  vec2 g10 = vec2(gx.y,gy.y);
  vec2 g01 = vec2(gx.z,gy.z);
  vec2 g11 = vec2(gx.w,gy.w);
  vec4 norm = 1.79284291400159 - 0.85373472095314 *
    vec4(dot(g00, g00), dot(g01, g01), dot(g10, g10), dot(g11, g11));
  g00 *= norm.x;
  g01 *= norm.y;
  g10 *= norm.z;
  g11 *= norm.w;
  float n00 = dot(g00, vec2(fx.x, fy.x));
  float n10 = dot(g10, vec2(fx.y, fy.y));
  float n01 = dot(g01, vec2(fx.z, fy.z));
  float n11 = dot(g11, vec2(fx.w, fy.w));
  vec2 fade_xy = fade(Pf.xy);
  vec2 n_x = mix(vec2(n00, n01), vec2(n10, n11), fade_xy.x);
  float n_xy = mix(n_x.x, n_x.y, fade_xy.y);
  return 2.3 * n_xy;
}
  
vec2 rotate2D (vec2 _st, float _angle) {
    _st -= 0.5;
    _st =  mat2(cos(_angle),-sin(_angle),
                sin(_angle),cos(_angle)) * _st;
    _st += 0.5;
    return _st;
}



  vec2 rotateUV(vec2 uv, vec2 pivot, float rotation) {
  mat2 rotation_matrix=mat2(  vec2(sin(rotation),-cos(rotation)),
                              vec2(cos(rotation),sin(rotation))
                              );
  uv -= pivot;
  uv= uv*rotation_matrix;
  uv += pivot;
  return uv;
}
  


  vec2 getRadialUv(vec2 uv)
{
	float angle = atan(uv.x, - uv.y);
	angle = abs(angle);
	
	vec2 radialUv = vec2(0.0);
	radialUv.x = angle / (PI * 2.0) + 0.5;
	radialUv.y = 1.0 - pow(1.0 - length(uv), 4.0);
	
	return radialUv;
}
 
  
void main() {
	vec2 uv = (gl_FragCoord.xy - u_resolution * .5) / u_resolution.yy + 0.5;
  
  float vTime = u_time * .5 ;
  float t = (u_time * .25) + length(uv -.5) ;
  
  vec2 rote = rotateUV(uv, vec2(.5), PI * vTime * .05);
  vec2 roteC = rotateUV(uv, vec2(.5), -PI * vTime * .05);

uv.x += cnoise(rote * 1.);
  
  uv.y += cnoise(roteC);






 
  
  
  vec3 color2 = vec3(rote.x, rote.y, 1.);

  
  coswarp(color2, 3.);
    coswarp(color2, 3.);
  

  
  
  float alpha = color2.r;
  

  
  
    
    vec4 tex = texture2D(uTexture, uv);
	
  
  vec3 color = vec3(tex.rgb);
  
    gl_FragColor = vec4(vec3(color.r, color.g, color.b), alpha);
}
</script>