Cold Lamps Rising

// composition: grass silhouette mass fills the bottom third and runs off the left edge; the last dusk light pools low-right,
// so the firefly cluster at the lower-left thirds crossing burns cold against the darkest ground. Upper right stays empty night.
// layering: night washes, dusk pool at the horizon, hazed far field, mid blades, deep silhouette blades, then the lights last.
const PALETTE = [
  "#12191c", // ground — blue-green night
  "#1d2c31", // air — cooler haze above the field
  "#3e5350", // dusk — the last light at the horizon
  "#0a0f10", // shadow — grass ink
  "#bcd977", // accent — firefly green, rationed
  "#eef3d4", // spark — the coldest cores
];

// x, y, core radius, brightness 0-1. Hand-placed: dense at the lower-left crossing,
// thinning up and to the right, three low ones caught down among the blades.
const LIGHTS = [
  [258, 528, 3.5, 1.00],
  [296, 557, 2.2, 0.82],
  [221, 497, 2.1, 0.74],
  [273, 474, 1.6, 0.60],
  [177, 553, 2.7, 0.86],
  [318, 509, 1.4, 0.50],
  [236, 579, 1.9, 0.66],
  [149, 501, 1.3, 0.45],
  [341, 566, 1.2, 0.42],
  [201, 455, 1.1, 0.38],
  [392, 470, 1.8, 0.62],
  [428, 523, 1.2, 0.40],
  [359, 404, 1.0, 0.34],
  [470, 437, 1.5, 0.52],
  [516, 487, 1.0, 0.30],
  [300, 372, 1.3, 0.44],
  [238, 335, 0.9, 0.28],
  [432, 356, 0.9, 0.26],
  [552, 402, 1.1, 0.32],
  [596, 300, 0.8, 0.22],
  [364, 249, 0.7, 0.18],
  [636, 459, 0.9, 0.24],
  [117, 627, 2.2, 0.58],
  [311, 649, 1.5, 0.42],
  [57, 566, 1.7, 0.50],
];

function blendTint(a, b, t) {
  return lerpColor(color(a), color(b), constrain(t, 0, 1));
}

// one blade: rises from (x, y), leans by `lean`, thins toward the tip
function blade(x, y, h, lean, w, col, name) {
  brush.noFill();
  brush.set(name || "2B", col, w);
  brush.beginShape(0.5);
  brush.vertex(x + randomGaussian(0, 1.6), y);
  brush.vertex(x + lean * 0.16 + randomGaussian(0, 2), y - h * 0.37);
  brush.vertex(x + lean * 0.55 + randomGaussian(0, 2.4), y - h * 0.73);
  brush.vertex(x + lean, y - h);
  brush.endShape(false);
}

// a foxtail head: a small dark swelling at the top of a tall stem
function seedHead(x, y, len, lean) {
  brush.noStroke();
  brush.fillBleed(0.3, "out");
  brush.fillTexture(0.6, 0.6);
  brush.fill("#0a0f10", 190 + random(-22, 30));
  brush.beginShape(0.6);
  brush.vertex(x, y);
  brush.vertex(x + lean * 0.3 - 4.5, y - len * 0.45);
  brush.vertex(x + lean, y - len);
  brush.vertex(x + lean * 0.3 + 4.2, y - len * 0.42);
  brush.endShape(true);
}

// a firefly: outer breath, mid glow, then a small hard core
function firefly(x, y, core, bright) {
  brush.noStroke();
  brush.fillTexture(0.28, 0.35);
  brush.fillBleed(0.6, "out");
  brush.fill("#bcd977", max(5, randomGaussian(17, 4) * bright));
  brush.circle(x + randomGaussian(0, 2.4), y + randomGaussian(0, 2.4), core * (7.4 + random(-1.2, 2.2)), true);

  brush.fillBleed(0.42, "out");
  brush.fill("#bcd977", max(16, randomGaussian(52, 10) * bright));
  brush.circle(x + randomGaussian(0, 1.2), y + randomGaussian(0, 1.2), core * (3.1 + random(-0.5, 0.9)), true);

  brush.fillBleed(0.2, "out");
  brush.fill(blendTint("#bcd977", "#eef3d4", 0.35 + bright * 0.55 + random(-0.12, 0.12)),
    max(72, randomGaussian(218, 16) * (0.5 + 0.5 * bright)));
  brush.circle(x, y, core * (1 + random(-0.12, 0.17)), true);
}

function setup() {
  createCanvas(800, 800, WEBGL);
  angleMode(DEGREES);
  brush.scaleBrushes(2.4);
  noLoop();
}

function draw() {
  translate(-width / 2, -height / 2);
  background("#12191c");

  brush.noStroke();

  // deepen the top of the sky so the night has a ceiling
  brush.fillBleed(0.4, "out");
  brush.fillTexture(0.35, 0.4);
  brush.fill("#0a0f10", 96);
  brush.rect(380, 90, 900, 260, "center");
  brush.fill("#0a0f10", 54);
  brush.rect(430, 250, 900, 180, "center");

  // a breath of cool air over the middle band, kept thin on the empty right
  brush.fill("#1d2c31", 44);
  brush.rect(300, 400, 720, 190, "center");

  // the last daylight, pooled low-right along the horizon and dying to the left
  brush.fillBleed(0.55, "out");
  brush.fillTexture(0.4, 0.45);
  brush.fill("#3e5350", 30);
  brush.rect(520, 552, 620, 130, "center");
  brush.fill("#3e5350", 34);
  brush.circle(748, 562, 84, true);
  brush.fill("#3e5350", 27);
  brush.circle(650, 552, 76, true);
  brush.fill("#3e5350", 18);
  brush.circle(556, 548, 66, true);
  brush.fill("#eef3d4", 14);
  brush.circle(772, 574, 52, true);

  // the far field: a hazed low band of short strokes, thinning where the noise dips
  for (let i = 0; i < 130; i++) {
    const x = constrain(randomGaussian(430, 260), -20, 830);
    if (noise(x * 0.0055, 4.1) < 0.36) continue;
    const y = 552 + randomGaussian(11, 8);
    const h = max(6, randomGaussian(17, 6));
    const near = constrain((x - 120) / 700, 0, 1);
    blade(x, y, h, randomGaussian(0, 5), 0.55 + random(0, 0.35),
      blendTint("#0a0f10", "#3e5350", 0.18 + near * 0.3 + random(-0.08, 0.08)));
  }

  // grass mass — soft dark pooling that turns the bottom into a body, heaviest left
  brush.noStroke();
  brush.fillBleed(0.45, "out");
  brush.fillTexture(0.5, 0.5);
  brush.fill("#0a0f10", 120);
  brush.rect(340, 748, 900, 180, "center");
  brush.fill("#0a0f10", 66);
  brush.rect(250, 640, 620, 150, "center");
  for (let i = 0; i < 22; i++) {
    const x = constrain(randomGaussian(300, 300), -40, 850);
    const y = 650 + randomGaussian(58, 44);
    if (noise(x * 0.004, y * 0.004, 9.2) < 0.3) continue;
    const left = constrain(1 - x / 800, 0, 1);
    brush.fill("#0a0f10", max(48, randomGaussian(86 + left * 44, 16)));
    brush.circle(x, y, max(26, randomGaussian(40, 8)), true);
  }

  // mid blades: the depth between the far haze and the front silhouette
  for (let i = 0; i < 92; i++) {
    const x = constrain(randomGaussian(320, 275), -30, 835);
    const y = 620 + randomGaussian(46, 34);
    if (noise(x * 0.005, 1.7) < 0.28) continue;
    const h = max(24, randomGaussian(62, 24));
    blade(x, y, h, randomGaussian(0, 16), 0.95 + random(0, 0.7),
      blendTint("#0a0f10", "#3e5350", 0.1 + random(0, 0.16)));
  }

  // seven long gestures: single stems that carry the field up out of its own mass
  blade(126, 802, 372, 44, 2.5, "#0a0f10", "charcoal");
  blade(74, 792, 316, -46, 2.2, "#0a0f10", "charcoal");
  blade(212, 806, 288, 92, 2.0, "#0a0f10", "charcoal");
  blade(302, 794, 326, 54, 2.3, "#0a0f10", "charcoal");
  blade(20, 760, 236, 30, 1.9, "#0a0f10", "charcoal");
  blade(556, 804, 250, -38, 2.1, "#0a0f10", "charcoal");
  blade(704, 808, 214, 40, 1.8, "#0a0f10", "charcoal");

  seedHead(168, 442, 46, 8);
  seedHead(356, 480, 38, -6);
  seedHead(30, 502, 34, 7);

  // near blades: the darkest ink, last of the structure, running off the bottom
  for (let i = 0; i < 54; i++) {
    const x = constrain(randomGaussian(280, 290), -40, 845);
    const y = 762 + randomGaussian(24, 26);
    const h = max(64, randomGaussian(128, 42));
    blade(x, y, h, randomGaussian(0, 26), 1.7 + random(0, 1.3), "#0a0f10");
  }

  // two blades leaning right across the dusk pool, to break its edge
  blade(648, 796, 196, -74, 2.4, "#0a0f10", "charcoal");
  blade(766, 782, 168, -52, 2.0, "#0a0f10", "charcoal");

  // the lights, last of all, so nothing sits on top of them
  brush.noStroke();
  for (let i = 0; i < LIGHTS.length; i++) {
    const l = LIGHTS[i];
    firefly(l[0] + randomGaussian(0, 2.6), l[1] + randomGaussian(0, 2.6), l[2], l[3]);
  }

  // two nearest lights get an extra wide breath — the out-of-focus ones
  brush.fillBleed(0.75, "out");
  brush.fillTexture(0.22, 0.3);
  brush.fill("#bcd977", 13);
  brush.circle(256, 530, 44, true);
  brush.fill("#bcd977", 10);
  brush.circle(178, 552, 34, true);
  brush.fill("#bcd977", 8);
  brush.circle(117, 626, 27, true);

  // one faint trail, where a light moved while the paper was wet
  brush.noFill();
  brush.set("2H", "#bcd977", 0.7);
  brush.beginShape(0.6);
  brush.vertex(392, 470);
  brush.vertex(412, 452);
  brush.vertex(438, 448);
  brush.endShape(false);
  brush.beginShape(0.6);
  brush.vertex(221, 497);
  brush.vertex(206, 482);
  brush.vertex(200, 466);
  brush.endShape(false);
}