// #include //ly.img.cesdk/shader/common/ubq_noise
uniform shader image;
uniform float2 imageSize;
uniform float time;
uniform float distortion;
uniform float distortion2;
uniform float speed;
uniform float rollSpeed;

half4 main(float2 coord) {
  float2 uv = coord / imageSize;
  uv.y = 1.0 - uv.y;
  float ty = time * speed * 17.346;
  float yt = uv.y - ty;

  // thick distortion
  float offset = noise2d(float2(yt * 3.0, 0.0)) * 0.2;
  offset = offset * distortion * offset * distortion * offset;
  // fine distortion
  offset += noise2d(float2(yt * 50.0, 0.0)) * distortion2 * 0.002;

  uv = float2(fract(uv.x + offset), fract(uv.y - time * rollSpeed));
  uv.y = 1.0 - uv.y;
  return image.eval(uv * imageSize);
}