/*{ "DESCRIPTION":"Nested orbit reliquary wreathed in blue ember smoke — torus hierarchy meets buoyant velocity ribbons.", "CATEGORIES":["generative"], "INPUTS":[ { "NAME":"speed", "TYPE":"float", "DEFAULT":1.3, "MIN":0.1, "MAX":3.0 }, { "NAME":"flowStrength", "TYPE":"float", "DEFAULT":1.4, "MIN":0.0, "MAX":3.0 }, { "NAME":"emberIntensity", "TYPE":"float", "DEFAULT":1.2, "MIN":0.0, "MAX":2.5 }, { "NAME":"smokeColor", "TYPE":"color", "DEFAULT":[0.18,0.42,0.68,1.0] }, { "NAME":"orbitColor", "TYPE":"color", "DEFAULT":[0.85,0.22,0.08,1.0] }, { "NAME":"accentColor", "TYPE":"color", "DEFAULT":[1.0,0.52,0.16,1.0] }, { "NAME":"density", "TYPE":"float", "DEFAULT":0.65, "MIN":0.0, "MAX":1.0 } ] }*/

#define PI 3.14159265359
#define TAU 6.28318530718

mat2 rot(float a){ float c=cos(a), s=sin(a); return mat2(c,-s,s,c); }

float hash21(vec2 p){
  return fract(sin(dot(p, vec2(127.1, 311.7))) * 43758.5453123);
}

float hash11(float p){
  return fract(sin(p * 78.233) * 43758.5453);
}

float noise2(vec2 p){
  vec2 i = floor(p);
  vec2 f = fract(p);
  f = f*f*(3.0-2.0*f);
  float a = hash21(i);
  float b = hash21(i + vec2(1.0, 0.0));
  float c = hash21(i + vec2(0.0, 1.0));
  float d = hash21(i + vec2(1.0, 1.0));
  return mix(mix(a,b,f.x), mix(c,d,f.x), f.y);
}

float fbm(vec2 p){
  float v = 0.0;
  float a = 0.5;
  for(int i = 0; i < 5; i++){
    v += a * noise2(p);
    p *= 2.0;
    a *= 0.5;
  }
  return v;
}

// Velocity field inspired by Parent 2's buoyant curl
vec2 velocityField(vec2 uv, float t){
  vec2 p = uv - 0.5;
  p.x *= RENDERSIZE.x / RENDERSIZE.y;
  float r = length(p);
  float angle = atan(p.y, p.x);
  vec2 v = vec2(sin(TAU * uv.x * 2.0), -cos(TAU * uv.y * 2.0));
  v += 0.5 * vec2(sin(TAU * (2.0 * uv.y + t * 0.08)),
                   cos(TAU * (2.0 * uv.x - t * 0.10)));
  v += 0.35 * vec2(cos(angle * 3.0 - t * 0.22), sin(angle * 2.0 + t * 0.28));
  v += vec2(0.0, 0.6 + 0.4 * smoothstep(0.0, 0.8, r));
  return v;
}

// Harmonic shell inspired by Parent 1's nested torus structure
float harmonicShell(vec2 p, float ph, float major, float tube, float carriers, float rate){
  float a = atan(p.y, p.x);
  float wave = a * carriers - TAU * ph * rate;
  float amp = 0.15;
  float ridge = cos(wave);
  float r = length(p.xy) - (major + amp * ridge);
  float d = abs(r) - tube * (1.0 - 0.15 + 0.15 * cos(wave + 0.8));
  return d;
}

void main(){
  vec2 uv = isf_FragNormCoord;
  float t = TIME * speed;
  vec2 aspect = vec2(RENDERSIZE.x / RENDERSIZE.y, 1.0);
  vec2 p = (uv - 0.5) * aspect;
  
  // Domain warp using velocity field — smoke flowing around orbits
  vec2 vel = velocityField(uv, t) * flowStrength;
  
  // Multiple layers of smoke ribbons flowing through the velocity field
  float smoke = 0.0;
  float glow = 0.0;
  
  for(int i = 0; i < 4; i++){
    float fi = float(i);
    float scale = 1.0 + fi * 0.5;
    vec2 wUV = uv - vel * (0.004 + fi * 0.002) * (1.0 + density);
    wUV = (wUV - 0.5) * aspect * scale;
    
    // Apply orbital rotation
    float rotAng = t * 0.15 + fi * 0.5;
    wUV = rot(rotAng) * wUV;
    
    // Harmonic shell — nested torus cross-sections
    float major = 0.18 + fi * 0.09;
    float tube = 0.012 + fi * 0.006;
    float carriers = 3.0 + fi * 3.0;
    float rate = 0.3 + fi * 0.15;
    float shell = harmonicShell(wUV, t, major, tube, carriers, rate);
    
    // Convert SDF to smoke density
    float band = exp(-abs(shell) * 60.0);
    smoke += band * (0.8 - fi * 0.12);
    
    // Ember ignition along ridge peaks
    float a = atan(wUV.y, wUV.x);
    float wave = a * carriers - TAU * t * rate;
    float ign = pow(max(0.0, cos(wave - 0.4)), 16.0);
    glow += ign * band * 2.0;
  }
  
  // Add turbulent smoke using fbm warped by velocity
  vec2 turbUV = uv + vel * 0.01;
  turbUV = (turbUV - 0.5) * aspect * 3.0;
  float turb = fbm(turbUV + t * 0.1);
  turb += 0.5 * fbm(turbUV * 2.0 - t * 0.15);
  smoke *= 0.5 + 0.5 * turb;
  
  // Additional flowing ember particles
  float embers = 0.0;
  for(int i = 0; i < 8; i++){
    float fi = float(i);
    vec2 ePos = vec2(
      0.5 + 0.3 * sin(t * 0.4 + fi * 1.7),
      0.5 + 0.35 * cos(t * 0.3 + fi * 2.3)
    );
    ePos += vel * 0.003;
    vec2 ed = (uv - ePos) * aspect;
    float ed_len = length(ed);
    embers += exp(-ed_len * 80.0) * (0.5 + 0.5 * sin(t * 3.0 + fi));
  }
  
  smoke = clamp(smoke, 0.0, 2.0);
  glow = clamp(glow, 0.0, 3.0);
  embers *= emberIntensity;
  
  // Color composition: blend Parent 1's teal/orange orbit palette with Parent 2's blue smoke
  vec3 smokeCol = smokeColor.rgb;
  vec3 orbitCol = orbitColor.rgb;
  vec3 accCol = accentColor.rgb;
  
  vec3 col = vec3(0.0);
  col += smokeCol * smoke * 0.7;
  col += orbitCol * glow * 0.6;
  col += accCol * embers * 1.5;
  
  // Contrast push
  col = pow(col, vec3(0.85));
  col *= 1.3;
  col = 1.0 - exp(-col * 1.8);
  
  // Vignette
  float vig = smoothstep(1.2, 0.3, length(p));
  col *= 0.5 + 0.5 * vig;
  
  gl_FragColor = vec4(col, 1.0);
}