radiance: match reference colors (asymmetric pink sky, saturated orange base, translucent pink-rimmed shell); ambient curl-noise shimmer

src/scripts/orb.js

@@ -93,7 +93,7 @@ P rest(uint idx) {
     float n = fbm(w + 1.6 * fbm(w * 0.8 + 3.1));
     n = clamp((n - 0.46) * 2.3 + 0.5, 0.0, 1.0);
     float keep = smoothstep(0.05, 0.7, n) - o.r.y * 0.7;
-    o.spark = step(0.94, o.r.z);
+    o.spark = step(0.92, o.r.z);
     o.n = n;
     if (keep < 0.0 && o.spark < 0.5) o.live = 0.0;
     vec3 p = rotX(rotY(d, t * 0.045 + 2.4 + uTilt.x), uTilt.y) * rad;
@@ -291,11 +291,18 @@ void main() {
   vec2 f = texture(uFlow, uv).xy;                           // texels per second
   vec2 flow = vec2(f.x / uSim.x * uView.x, f.y / uSim.y * uView.y) / uR;  // radii per second
 
+  // ambient shimmer: a slow curl-noise wind keeps the particles streaming
+  vec3 np = vec3(p.xy * 2.4 + vec2(0.0, uTime * 0.05), uTime * 0.16);
+  float e = 0.03;
+  float nx = vnoise(np + vec3(e, 0.0, 0.0)) - vnoise(np - vec3(e, 0.0, 0.0));
+  float ny = vnoise(np + vec3(0.0, e, 0.0)) - vnoise(np - vec3(0.0, e, 0.0));
+  vec2 wind = vec2(ny, -nx) / (2.0 * e);
+
   float light = p.kind;                                       // corona sparks are lighter
   float k = (8.0 + 2.5 * light) * (0.65 + 0.7 * p.r.w);       // spring back home
   float c = 2.0 * sqrt(k) * 0.45;                             // under-damped: a little bounce on the way home
   float follow = 9.0 + 6.0 * light;                           // how hard the flow drags it
-  vec2 acc = -k * disp - c * vel + follow * (flow * uGain * (1.0 + 0.8 * light) - vel);
+  vec2 acc = -k * disp - c * vel + follow * (flow * uGain * (1.0 + 0.8 * light) - vel) + wind * (0.14 + 0.7 * light);
   vel += acc * uDt;
   disp += vel * uDt;
   float m = length(disp);
@@ -334,10 +341,10 @@ void main() {
   float persp = 1.0;
 
   if (p.kind < 0.5) {
-    vec3 warm = mix(vec3(0.90, 0.22, 0.17), vec3(0.99, 0.50, 0.30), p.r.w);
+    vec3 warm = mix(vec3(0.94, 0.27, 0.20), vec3(1.0, 0.52, 0.32), p.r.w);
     warm = mix(warm, vec3(1.0, 0.72, 0.42), smoothstep(0.1, 0.45, 1.0 - p.n) * 0.8);
     col = vec4(mix(warm, vec3(1.0, 0.97, 0.84), p.spark), mix(0.85, 0.95, p.spark));
-    size = mix(1.6 + p.r.y * 1.6 + p.n * 1.0, 3.2 + p.r.w * 2.6, p.spark);
+    size = mix(1.25 + p.r.y * 1.3 + p.n * 0.9, 2.6 + p.r.w * 2.4, p.spark);
     float tw = 0.5 + 0.5 * sin(uTime * (1.2 + p.r.x * 2.5) + p.r.w * 40.0);
     col.a *= mix(1.0, tw, p.spark);
     vGlow = p.spark;
@@ -402,16 +409,16 @@ vec3 ramp(float y) {
   const vec3 c6 = vec3(0.933, 0.682, 0.541);
   const vec3 c7 = vec3(0.933, 0.600, 0.447);
   const vec3 c8 = vec3(0.922, 0.545, 0.388);
-  const vec3 c9 = vec3(0.937, 0.506, 0.361);
+  const vec3 c9 = vec3(0.937, 0.53, 0.385);
   vec3 c = mix(c0, c1, smoothstep(0.00, 0.14, y));
   c = mix(c, c2, smoothstep(0.14, 0.30, y));
   c = mix(c, c3, smoothstep(0.30, 0.52, y));
   c = mix(c, c4, smoothstep(0.52, 0.62, y));
   c = mix(c, c5, smoothstep(0.62, 0.70, y));
-  c = mix(c, c6, smoothstep(0.70, 0.79, y));
+  c = mix(c, c6, smoothstep(0.70, 0.82, y));
-  c = mix(c, c7, smoothstep(0.79, 0.87, y));
+  c = mix(c, c7, smoothstep(0.82, 0.90, y));
-  c = mix(c, c8, smoothstep(0.87, 0.94, y));
+  c = mix(c, c8, smoothstep(0.90, 0.96, y));
-  c = mix(c, c9, smoothstep(0.94, 1.00, y));
+  c = mix(c, c9, smoothstep(0.96, 1.00, y));
   return c;
 }
 
@@ -425,9 +432,11 @@ void main() {
   y += clamp(flow.y / uSim.y, -0.2, 0.2) * 0.12 - clamp(flow.x / uSim.x, -0.2, 0.2) * 0.04;
   vec3 col = ramp(clamp(y, 0.0, 1.0));
 
-  vec2 d = (uv - vec2(0.5, 0.6)) / vec2(1.15, 0.8);
+  float top = 1.0 - smoothstep(0.45, 0.9, 1.0 - uv.y);          // fades out toward the orange bottom
-  float v = clamp((length(d) - 0.45) / 0.55, 0.0, 1.0) * 0.65;
+  float right = smoothstep(0.55, 1.0, uv.x) * (0.55 + 0.45 * smoothstep(0.0, 0.5, uv.y));
-  col = mix(col, vec3(0.984, 0.737, 0.651), v);
+  col = mix(col, vec3(0.984, 0.78, 0.67), clamp(right * 0.95, 0.0, 1.0) * top);
+  float left = (1.0 - smoothstep(0.0, 0.3, uv.x)) * smoothstep(0.3, 0.95, uv.y);
+  col = mix(col, vec3(0.97, 0.885, 0.80), left * 0.35 * top);
 
   float wash = 0.4 * (1.0 - exp(-dye * 1.4));
   col = mix(col, vec3(0.98, 0.93, 0.89), wash);
@@ -459,16 +468,16 @@ void main() {
   vec3 n = vec3(d.x, -d.y, z);
 
   // glassy body: lighter top-left, deeper orange bottom-right
-  vec3 top = vec3(0.992, 0.76, 0.52);
+  vec3 top = vec3(1.0, 0.77, 0.56);
-  vec3 bot = vec3(0.975, 0.55, 0.38);
+  vec3 bot = vec3(1.0, 0.56, 0.42);
   float lit = clamp(0.5 + 0.5 * dot(normalize(n), normalize(vec3(-0.45, 0.6, 0.65))), 0.0, 1.0);
   vec3 body = mix(bot, top, lit);
 
   // fresnel rim, pale pink-white
-  float fres = pow(1.0 - z, 2.0);
+  float fres = pow(1.0 - z, 1.8);
-  vec3 rim = vec3(1.0, 0.89, 0.86);
+  vec3 rim = vec3(1.0, 0.85, 0.83);
   vec3 col = mix(body, rim, clamp(fres * 1.15, 0.0, 1.0));
-  float a = mix(0.7, 0.97, fres);
+  float a = mix(0.58, 0.97, fres);
 
   // crisp bright edge line
   float ring = smoothstep(0.955, 0.985, r) * (1.0 - smoothstep(0.985, 1.004, r));