【GLSL】RGBの縞々のリング

See the Pen RGB stripe rings by aadebdeb (@aadebdeb) on CodePen.

#define TWO_PI 6.2831853

precision mediump float;

uniform float u_time;
uniform vec2 u_mouse;
uniform vec2 u_resolution;


float wave(in vec2 position, in vec2 center, in float scale, in float offset) {
  float d = distance(position, center);
  return (sin(offset + d * scale) + 1.) * .5;
}

void main(void) {

  vec2 center = u_resolution / 2.;
  float radius = 200.;
  float time = u_time * 0.004;
  vec2 mouse = u_mouse / u_resolution;
  vec3 scales = vec3(mouse.x * 0.1, mouse.y * 0.1, (1.0 - (mouse.x + mouse.y) * 2.0) * 0.1);
  vec3 color = vec3(wave(gl_FragCoord.xy, center + radius * vec2(cos(time), sin(time)), scales.r, time),
                    wave(gl_FragCoord.xy, center + radius * vec2(cos(time + TWO_PI / 3.), sin(time + TWO_PI / 3.)), scales.g, time),
                    wave(gl_FragCoord.xy, center + radius * vec2(cos(time + TWO_PI / 3. * 2.), sin(time + TWO_PI / 3. * 2.)), scales.b, time));

  gl_FragColor = vec4(color, 1.0);
}