Ink Bloom

A canvas and a module script, nothing to install. Set canvas.dataset.tps from your stream, or call canvas.token() once per token.

<canvas id="shader-ink-bloom" data-tps="10" data-color="#3d7bff" style="display:block;width:100%;height:240px;border-radius:12px"></canvas>
<script type="module">
  // Set canvas.dataset.tps from your stream, or call canvas.token() per token.
  const canvas = document.getElementById("shader-ink-bloom");
  const gl = canvas.getContext("webgl2", { alpha: false, antialias: false });
  const fragment = `#version 300 es
precision highp float;
uniform vec3 iResolution;
uniform float iTime;
uniform float uTokens;
uniform float uTps;
uniform vec3 uColor;
out vec4 outColor;
// Gradient noise on a lattice that repeats every PER cells. Moving offsets are
// wrapped to whole periods, so the motion loops without a seam.
const float PER = 32.0;
// Octave turn and scale: an integer matrix keeps the lattice periodic.
const mat2 OCT = mat2(2.0, -1.0, 1.0, 2.0);

vec2 grad(vec2 i) {
  i = mod(i, PER);
  vec3 q = fract(vec3(i.xyx) * vec3(0.1031, 0.1030, 0.0973));
  q += dot(q, q.yzx + 33.33);
  return fract((q.xx + q.yz) * q.zy) * 2.0 - 1.0;
}

float noise(vec2 p) {
  vec2 i = floor(p), f = fract(p);
  vec2 u = f * f * f * (f * (f * 6.0 - 15.0) + 10.0);
  float a = dot(grad(i), f);
  float b = dot(grad(i + vec2(1.0, 0.0)), f - vec2(1.0, 0.0));
  float c = dot(grad(i + vec2(0.0, 1.0)), f - vec2(0.0, 1.0));
  float d = dot(grad(i + vec2(1.0, 1.0)), f - vec2(1.0, 1.0));
  return mix(mix(a, b, u.x), mix(c, d, u.x), u.y);
}

// A phase that climbs with x but wraps to the noise period.
float wrapP(float x) { return mod(x, PER); }

// Rotate a colour around the grey axis: hue shifts that follow uColor.
vec3 hue(vec3 c, float a) {
  const vec3 k = vec3(0.57735);
  float ca = cos(a);
  return c * ca + cross(k, c) * sin(a) + k * dot(k, c) * (1.0 - ca);
}

float hash12(vec2 p) {
  vec3 q = fract(vec3(p.xyx) * 0.1031);
  q += dot(q, q.yzx + 33.33);
  return fract((q.x + q.y) * q.z);
}

// Soft shoulder tone map plus a one step dither against banding.
vec3 finish(vec3 c, vec2 fc) {
  c = 1.0 - exp(-max(c, 0.0));
  return c + (hash12(fc) - 0.5) / 255.0;
}

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
  vec2 uv = (fragCoord - 0.5 * iResolution.xy) / iResolution.y;
  float e = 1.0 - exp(-uTps / 80.0);

  // six drop slots; each runs its own clock and a fresh drop is born every whole
  // cycle, so a faster stream means more births and quicker unfurling. Clocks
  // wrap by 512 whole cycles and drop seeds use the cycle mod 512: no seam.
  float D = 0.0, F = 0.0;
  for (int i = 0; i < 6; i++) {
    float fi = float(i);
    float ph = mod(uTokens * 0.0021 * (0.82 + 0.08 * fi), 512.0)
             + mod(iTime * (0.016 + 0.003 * fi), 512.0) + fi * 0.37;
    float n = mod(floor(ph), 512.0);
    float age = fract(ph);
    vec2 sd = vec2(n, fi * 7.0);
    float h1 = hash12(sd + 0.5), h2 = hash12(sd + 3.7), h3 = hash12(sd + 9.1);
    // depth: far drops are smaller, paler and lower in contrast
    float z = fract(h3 + fi * 0.618);
    float sz = mix(1.0, 0.5, z);
    float grow = pow(age, 0.55);
    vec2 pos = vec2(-0.85 + 1.7 * (fi + 0.1 + 0.8 * h1) / 6.0,
                    0.3 - 0.22 * h2 - 0.45 * pow(age, 0.8) * sz);
    float R = (0.03 + (0.3 + 0.08 * e) * grow) * sz;
    vec2 lp = (uv - pos) / R;
    vec2 off = vec2(h1, h2) * 13.0 + fi * 3.1;
    // tendrils churn with the drop's age and with every token
    float tw = age * 1.8 + wrapP(uTokens * 0.006 + fi * 5.0);
    // the plume curls: a soft warp that keeps turning as the drop ages
    vec2 w = vec2(noise(lp * 1.1 + off + vec2(0.0, tw)), noise(lp * 1.1 + off.yx + vec2(tw, 5.0)));
    vec2 q = lp + w * (0.7 + 1.1 * grow);
    // a rolling cap below with a wake trailing up behind it
    float r = length((q - vec2(0.0, 0.35 * grow)) * vec2(1.0, 0.75));
    float env = smoothstep(1.3, 0.25, r) * smoothstep(0.0, 0.1, age) * smoothstep(1.0, 0.62, age);
    float n2 = noise(q * 2.4 + off + vec2(0.0, -tw));
    float fil = exp(-abs(n2) / (0.035 + fwidth(n2)));
    float n3 = noise(q * 4.8 + off.yx - vec2(tw, 0.0));
    fil += 0.6 * exp(-abs(n3) / (0.04 + fwidth(n3))) * smoothstep(0.2, 0.9, grow);
    float body = smoothstep(1.05, 0.15, r);
    float amt = env * mix(1.0, 0.45, z) * (1.15 - 0.45 * age);
    D += amt * (body * 0.6 + fil * 0.35);
    F += amt * fil * mix(1.0, 0.3, z);
  }

  // deep water lit from above, falling off to the dark stage at the edges
  float light = exp(-length((uv - vec2(0.0, 0.3)) * vec2(0.42, 0.85)) * 1.3);
  vec3 water = mix(vec3(0.5, 0.58, 0.66), uColor, 0.15);
  vec3 col = water * (0.025 + 0.3 * light);
  // the dye catches the light: thin ink glows in the accent, dense ink deepens
  float cover = 1.0 - exp(-D * 3.0);
  vec3 dye = mix(mix(uColor, vec3(1.0), 0.12) * 1.5, uColor * 0.6, smoothstep(0.45, 1.0, cover));
  dye *= (0.5 + 0.9 * light) * (0.85 + 0.4 * e);
  col = mix(col, dye, cover * 0.92);
  // the tendril edges stay dark: crisp, high contrast filaments
  col = mix(col, uColor * 0.05, clamp(F * 0.85, 0.0, 0.88));
  // a little extra saturation so the dye stays vivid through the tone map
  col = max(mix(vec3(dot(col, vec3(0.3, 0.55, 0.15))), col, 1.35), 0.0);
  col *= 1.0 - 0.35 * dot(uv * vec2(0.55, 1.0), uv * vec2(0.55, 1.0));
  fragColor = vec4(finish(col, fragCoord), 1.0);
}

void main() {
  mainImage(outColor, gl_FragCoord.xy);
  outColor.a = 1.0;
}
`;
  const vertex = `#version 300 es
void main() {
  vec2 p = vec2((gl_VertexID << 1) & 2, gl_VertexID & 2);
  gl_Position = vec4(p * 2.0 - 1.0, 0.0, 1.0);
}
`;
  const compile = (type, src) => {
    const s = gl.createShader(type);
    gl.shaderSource(s, src);
    gl.compileShader(s);
    if (!gl.getShaderParameter(s, gl.COMPILE_STATUS)) throw new Error(gl.getShaderInfoLog(s));
    return s;
  };
  const program = gl.createProgram();
  gl.attachShader(program, compile(gl.VERTEX_SHADER, vertex));
  gl.attachShader(program, compile(gl.FRAGMENT_SHADER, fragment));
  gl.linkProgram(program);
  gl.useProgram(program);
  const u = (n) => gl.getUniformLocation(program, n);
  const [res, time, tokens, rate, color] = ["iResolution", "iTime", "uTokens", "uTps", "uColor"].map(u);
  const hex = parseInt((canvas.dataset.color || "#7c5cff").slice(1), 16);
  gl.uniform3f(color, ((hex >> 16) & 255) / 255, ((hex >> 8) & 255) / 255, (hex & 255) / 255);

  // canvas.token(): count real tokens and derive the rate from the last second.
  const stamps = [];
  canvas.token = () => {
    stamps.push(performance.now());
    canvas.dataset.tps = "auto";
  };
  const still = matchMedia("(prefers-reduced-motion: reduce)").matches;
  let count = 0, last = performance.now(), visible = true, frame = 0;
  new IntersectionObserver(([e]) => {
    visible = e.isIntersecting;
    if (visible && !frame) frame = requestAnimationFrame(draw);
  }).observe(canvas);

  function draw(now) {
    frame = 0;
    const dt = Math.min((now - last) / 1000, 0.1);
    last = now;
    while (stamps.length && now - stamps[0] > 1000) stamps.shift();
    const wobble = 1 + 0.25 * Math.sin(now / 588) + 0.15 * Math.sin(now / 233 + 1) + 0.08 * Math.sin(now / 91 + 2);
    const tps = canvas.dataset.tps === "auto" ? stamps.length : Number(canvas.dataset.tps) * wobble;
    count += tps * dt;
    const dpr = Math.min(devicePixelRatio || 1, 2);
    const w = Math.round(canvas.clientWidth * dpr), h = Math.round(canvas.clientHeight * dpr);
    if (canvas.width !== w || canvas.height !== h) { canvas.width = w; canvas.height = h; }
    gl.viewport(0, 0, w, h);
    gl.uniform3f(res, w, h, 1);
    gl.uniform1f(time, still ? 2 : now / 1000);
    gl.uniform1f(tokens, still ? Number(canvas.dataset.tps) * 2 : count);
    gl.uniform1f(rate, tps);
    gl.drawArrays(gl.TRIANGLES, 0, 3);
    if (visible && !still) frame = requestAnimationFrame(draw);
  }
  frame = requestAnimationFrame(draw);
</script>

// Inputs the site passes in, as constants for Shadertoy.
// uTps: tokens per second. uTokens: tokens so far. uColor: the accent.
#define uTps 10.0
#define uTokens (iTime * uTps)
#define uColor vec3(0.239, 0.482, 1.000)

// Gradient noise on a lattice that repeats every PER cells. Moving offsets are
// wrapped to whole periods, so the motion loops without a seam.
const float PER = 32.0;
// Octave turn and scale: an integer matrix keeps the lattice periodic.
const mat2 OCT = mat2(2.0, -1.0, 1.0, 2.0);

vec2 grad(vec2 i) {
  i = mod(i, PER);
  vec3 q = fract(vec3(i.xyx) * vec3(0.1031, 0.1030, 0.0973));
  q += dot(q, q.yzx + 33.33);
  return fract((q.xx + q.yz) * q.zy) * 2.0 - 1.0;
}

float noise(vec2 p) {
  vec2 i = floor(p), f = fract(p);
  vec2 u = f * f * f * (f * (f * 6.0 - 15.0) + 10.0);
  float a = dot(grad(i), f);
  float b = dot(grad(i + vec2(1.0, 0.0)), f - vec2(1.0, 0.0));
  float c = dot(grad(i + vec2(0.0, 1.0)), f - vec2(0.0, 1.0));
  float d = dot(grad(i + vec2(1.0, 1.0)), f - vec2(1.0, 1.0));
  return mix(mix(a, b, u.x), mix(c, d, u.x), u.y);
}

// A phase that climbs with x but wraps to the noise period.
float wrapP(float x) { return mod(x, PER); }

// Rotate a colour around the grey axis: hue shifts that follow uColor.
vec3 hue(vec3 c, float a) {
  const vec3 k = vec3(0.57735);
  float ca = cos(a);
  return c * ca + cross(k, c) * sin(a) + k * dot(k, c) * (1.0 - ca);
}

float hash12(vec2 p) {
  vec3 q = fract(vec3(p.xyx) * 0.1031);
  q += dot(q, q.yzx + 33.33);
  return fract((q.x + q.y) * q.z);
}

// Soft shoulder tone map plus a one step dither against banding.
vec3 finish(vec3 c, vec2 fc) {
  c = 1.0 - exp(-max(c, 0.0));
  return c + (hash12(fc) - 0.5) / 255.0;
}

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
  vec2 uv = (fragCoord - 0.5 * iResolution.xy) / iResolution.y;
  float e = 1.0 - exp(-uTps / 80.0);

  // six drop slots; each runs its own clock and a fresh drop is born every whole
  // cycle, so a faster stream means more births and quicker unfurling. Clocks
  // wrap by 512 whole cycles and drop seeds use the cycle mod 512: no seam.
  float D = 0.0, F = 0.0;
  for (int i = 0; i < 6; i++) {
    float fi = float(i);
    float ph = mod(uTokens * 0.0021 * (0.82 + 0.08 * fi), 512.0)
             + mod(iTime * (0.016 + 0.003 * fi), 512.0) + fi * 0.37;
    float n = mod(floor(ph), 512.0);
    float age = fract(ph);
    vec2 sd = vec2(n, fi * 7.0);
    float h1 = hash12(sd + 0.5), h2 = hash12(sd + 3.7), h3 = hash12(sd + 9.1);
    // depth: far drops are smaller, paler and lower in contrast
    float z = fract(h3 + fi * 0.618);
    float sz = mix(1.0, 0.5, z);
    float grow = pow(age, 0.55);
    vec2 pos = vec2(-0.85 + 1.7 * (fi + 0.1 + 0.8 * h1) / 6.0,
                    0.3 - 0.22 * h2 - 0.45 * pow(age, 0.8) * sz);
    float R = (0.03 + (0.3 + 0.08 * e) * grow) * sz;
    vec2 lp = (uv - pos) / R;
    vec2 off = vec2(h1, h2) * 13.0 + fi * 3.1;
    // tendrils churn with the drop's age and with every token
    float tw = age * 1.8 + wrapP(uTokens * 0.006 + fi * 5.0);
    // the plume curls: a soft warp that keeps turning as the drop ages
    vec2 w = vec2(noise(lp * 1.1 + off + vec2(0.0, tw)), noise(lp * 1.1 + off.yx + vec2(tw, 5.0)));
    vec2 q = lp + w * (0.7 + 1.1 * grow);
    // a rolling cap below with a wake trailing up behind it
    float r = length((q - vec2(0.0, 0.35 * grow)) * vec2(1.0, 0.75));
    float env = smoothstep(1.3, 0.25, r) * smoothstep(0.0, 0.1, age) * smoothstep(1.0, 0.62, age);
    float n2 = noise(q * 2.4 + off + vec2(0.0, -tw));
    float fil = exp(-abs(n2) / (0.035 + fwidth(n2)));
    float n3 = noise(q * 4.8 + off.yx - vec2(tw, 0.0));
    fil += 0.6 * exp(-abs(n3) / (0.04 + fwidth(n3))) * smoothstep(0.2, 0.9, grow);
    float body = smoothstep(1.05, 0.15, r);
    float amt = env * mix(1.0, 0.45, z) * (1.15 - 0.45 * age);
    D += amt * (body * 0.6 + fil * 0.35);
    F += amt * fil * mix(1.0, 0.3, z);
  }

  // deep water lit from above, falling off to the dark stage at the edges
  float light = exp(-length((uv - vec2(0.0, 0.3)) * vec2(0.42, 0.85)) * 1.3);
  vec3 water = mix(vec3(0.5, 0.58, 0.66), uColor, 0.15);
  vec3 col = water * (0.025 + 0.3 * light);
  // the dye catches the light: thin ink glows in the accent, dense ink deepens
  float cover = 1.0 - exp(-D * 3.0);
  vec3 dye = mix(mix(uColor, vec3(1.0), 0.12) * 1.5, uColor * 0.6, smoothstep(0.45, 1.0, cover));
  dye *= (0.5 + 0.9 * light) * (0.85 + 0.4 * e);
  col = mix(col, dye, cover * 0.92);
  // the tendril edges stay dark: crisp, high contrast filaments
  col = mix(col, uColor * 0.05, clamp(F * 0.85, 0.0, 0.88));
  // a little extra saturation so the dye stays vivid through the tone map
  col = max(mix(vec3(dot(col, vec3(0.3, 0.55, 0.15))), col, 1.35), 0.0);
  col *= 1.0 - 0.35 * dot(uv * vec2(0.55, 1.0), uv * vec2(0.55, 1.0));
  fragColor = vec4(finish(col, fragCoord), 1.0);
}

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