​

  // x,y coordinates, given from the vertex shader

  varying vec2 vTexCoord;

​

  // the canvas contents, given from filter()

  uniform sampler2D tex0;

  // other useful information from the canvas

  uniform vec2 texelSize;

  uniform vec2 canvasSize;

  // a custom variable from this sketch

  uniform float darkness;

​

​

  void main() {

​

    float dist = sqrt( ( 0.5 - vTexCoord.x )*( 0.5 - vTexCoord.x ) + ( 0.5 - vTexCoord.y )*( 0.5 - vTexCoord.y ) );

​

    float rot = atan(( 0.5 - vTexCoord.y ) / ( 0.5 - vTexCoord.x ));

    if(vTexCoord.x < 0.5){

      rot += 3.14159265359; 

}

    if(dist<1.0){

      rot += 1.0/((dist+0.03)*4.0);

}

​

    vec2 coord = vec2(0.5 + cos(rot)*dist, 0.5 + sin(rot)*dist);

    // get the color at current pixel

    // no

    vec4 color = texture2D(tex0, coord);

    // set the output color

    color *= 1.0;

    gl_FragColor = vec4(color.rgb, 1.0);

  }

`

​

let img

let Filter

​

function preload(){

  img = loadImage("/image.png")

}

​

function setup() {

  createCanvas(808, 459);

  Filter = createFilterShader(pixShader)

}

​

function draw() {

  background(10);

  image(img,0,0)

  filter(Filter)

}