// Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.  

CCEffect %{
  techniques:
  - passes:
    - vert: vs
      frag: fs
      blendState:
        targets:
        - blend: true
      rasterizerState:
        cullMode: none
      properties:
        texture: { value: white }
        alphaThreshold: { value: 0.5 }
}%


CCProgram vs %{
  precision highp float;

  #include <cc-global>
  #include <cc-local>

  in vec3 a_position;
  in vec4 a_color;
  out vec4 v_color;

  #if USE_TEXTURE
  in vec2 a_uv0;
  out vec2 v_uv0;
  #endif

  void main () {
    vec4 pos = vec4(a_position, 1);

    #if CC_USE_MODEL
    pos = cc_matViewProj * cc_matWorld * pos;
    #else
    pos = cc_matViewProj * pos;
    #endif

    #if USE_TEXTURE
    v_uv0 = a_uv0;
    #endif

    v_color = a_color;

    gl_Position = pos;
  }
}%


CCProgram fs %{
  precision highp float;
  
  #include <cc-global>
  #include <alpha-test>
  #include <texture>

  in vec4 v_color;

  #if USE_TEXTURE
  in vec2 v_uv0;
  uniform sampler2D texture;
  #endif

  const vec2 iResolution = vec2(0.5, 0.5);
  float hash21(vec2 x) {
    return fract(cos(mod(dot(x, vec2(13.9898, 8.141)), 3.14)) * 43758.5453);
  }

  vec2 hash22(vec2 uv) {
    uv = vec2(dot(uv, vec2(127.1,311.7)),
              dot(uv, vec2(269.5,183.3)));
    return 2.0 * fract(sin(uv) * 43758.5453123) - 1.0;
  }

  float perlinNoise(vec2 uv) {
    vec2 iuv = floor(uv);
    vec2 fuv = fract(uv);
    vec2 blur = smoothstep(.0, 1., fuv);
    vec2 bl = vec2(.0, .0);
    vec2 br = vec2(1., .0);
    vec2 tl = vec2(.0, 1.);
    vec2 tr = vec2(1., 1.);
    vec2 bln = hash22(iuv + bl);
    vec2 brn = hash22(iuv + br);
    vec2 tln = hash22(iuv + tl);
    vec2 trn = hash22(iuv + tr);
    float b  = mix(dot(bln, fuv - bl), dot(brn, fuv - br), blur.x);
    float t  = mix(dot(tln, fuv - tl), dot(trn, fuv - tr), blur.x);
    float c = mix(b, t, blur.y);
    float rs = 2.0 * texture2D(texture, vec2(uv.x,0.75)).r;

    return (c * rs);
  }

  float fbm(vec2 uv, int octaves) {
    float value = .0;
    float amplitude  = .5;
    float freq = 2.0;

    for(int i = 0; i < 30; i++)
    {
      value += perlinNoise(uv) * amplitude;
        uv *= freq;
        amplitude *= .5;
    }
    return value;
  }

  mat2 R(float q) {
    return mat2(cos(q), sin(q), -sin(q), cos(q));
  }

  void main () {
    vec2 uvv = (v_uv0 - 0.5) / iResolution.y;
    vec3 col1, col2;
    uvv.xy += fbm(uvv.yx + cc_time.x * 0.5, 30);
    float dist1 = abs(uvv.y);

    col1 = vec3(1.0) * mix(0.0, 0.05, hash21(vec2(sin(cc_time.x)))) / dist1;

    vec4 o = vec4(0.0);
    vec2 uv = v_uv0;
    float t = cc_time.x, e, s, g, k = 0.01;

    for(float i = 0.0; i < 100.0; i++)
    {
        g += max(k, e * 0.2);
        vec3 p = vec3((uv - 0.6) / iResolution.y * g + iResolution / iResolution.y * R(t + g * 0.5) * 0.5, g + t / 0.3);
        e = 0.3 - dot(p.xy, p.xy);
        for (float s = 2.0; s < 100.0; s ++) {
            p.yz *= R(s);
            e += abs(dot(sin(p * s + t * s * 0.2) / s, p - p + 1.0));
        }
        o += o.w * min(e * o + (sin(vec4(1.0, 2.0, 3.0, 1.0) - p.z * 0.3) * 0.6 - 0.4), k) * k;
    }
    vec3 finalColor = mix(o.rgb, col1, 0.3);
    finalColor *= min(1.0, 1.0 + cos(0.15 * t)) + min(1.0, max(0.0, -2.0 - 4.0 * cos(0.15 * t))) * smoothstep(0.85, 1.0, fract(sin(t) * 43758.5453));

    gl_FragColor = vec4(finalColor, 1.0);
  }
}%