# FAQ Accordion in React Beside an Opal Glass Globe Lamp in WebGL That Glows Brighter as Each Answer Opens > Free React FAQ accordion with aria-expanded buttons, smooth height and one or many open, beside a WebGL opal glass lamp that brightens per answer. A shadcn/ui block from the [@weinc](https://we.inc/components?utm_source=shadcn.exchange) registry, listed on [shadcn.exchange](https://shadcn.exchange/r/weinc/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens). - Page, with a live preview: https://shadcn.exchange/r/weinc/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens - Screenshot: https://shadcn.exchange/shot/weinc/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens/light.png - Registry item: https://we.inc/r/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens.json - Listed: 2026-10-28, source last changed 2026-10-28 ## Install ```bash npx shadcn@latest add https://shadcn.exchange/r/weinc/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens.json ``` Run it in a project that has shadcn/ui set up. It adds the files below and installs what they depend on. ## Dependencies - npm packages: `framer-motion` ## Files ### `components/we-inc/faq-accordion-in-react-beside-an-opal-glass-globe-lamp-in-webgl-that-glows-brighter-as-each-answer-opens.tsx` ```tsx import { useEffect, useId, useRef, useState, type KeyboardEvent } from "react"; import { useReducedMotion } from "framer-motion"; /** The questions. Swap these for your own; the lamp brightens with every answer that is open. */ const faqs = [ { q: "What bulb does the lamp take?", a: "A single E14 LED of up to 6 watts, warm white. One ships in the box, and the opal glass hides its shape completely, so any shape of bulb works." }, { q: "Can I dim it?", a: "Yes. The cord switch has a soft dimmer: hold it down and the light slowly falls to a glow, tap it once to go back to full." }, { q: "Is the glass hand blown?", a: "Every globe is mouth blown into a beechwood mould and then acid etched inside and out, which gives the milky, even finish with no hot spot." }, { q: "How long does delivery take?", a: "Three to five working days in most of Europe and North America. Each lamp travels in a moulded pulp cradle, so nothing has to be thrown away." }, { q: "What if the glass breaks?", a: "Send us a photo within two years and we post a new globe free of charge. After that, replacement globes are sold on their own." }, ]; const OPEN_AT_START = [0]; // which answers are open when the page loads const GLOW_STEP = 0.145; // how much each open answer adds to the lamp (0 to 1); one open answer is a low glow const GLOW_FIRST = 0.42; // brightness with one answer open const WALL = "#16232e"; // the painted wall and the panel the questions sit on const INK = "#efe6d8"; const GROTESK = '"Inter Tight", "Inter", ui-sans-serif, system-ui, sans-serif'; /* ---- photoreal kit (pasted, see PHOTOREAL-KIT.md) ---- */ const FULLSCREEN_VS = `#version 300 es out vec2 vUv; void main() { vec2 p = vec2(float((gl_VertexID << 1) & 2), float(gl_VertexID & 2)); vUv = p; gl_Position = vec4(p * 2.0 - 1.0, 0.0, 1.0); }`; const GLSL_HEADER = `#version 300 es precision highp float; uniform vec2 uRes; // drawing buffer size in pixels uniform float uFrame; // sample index since the last reset (drives every random number) uniform float uTime; // seconds, for things that really move uniform vec3 uCamPos, uCamRt, uCamUp, uCamFw; uniform float uTan, uAspect, uAperture, uFocus; uniform vec2 uShift; // lens shift (architectural framing): move the subject in frame without tilting verticals out vec4 o;`; const GLSL_COMMON = ` #define PI 3.14159265359 float saturate(float x) { return clamp(x, 0.0, 1.0); } float hash12(vec2 p) { vec3 p3 = fract(vec3(p.xyx) * 0.1031); p3 += dot(p3, p3.yzx + 33.33); return fract((p3.x + p3.y) * p3.z); } float hash13(vec3 p3) { p3 = fract(p3 * 0.1031); p3 += dot(p3, p3.zyx + 31.32); return fract((p3.x + p3.y) * p3.z); } float ign(vec2 p) { return fract(52.9829189 * fract(dot(p, vec2(0.06711056, 0.00583715)))); } float vnoise(vec2 p) { vec2 i = floor(p), f = fract(p); f = f * f * (3.0 - 2.0 * f); return mix(mix(hash12(i), hash12(i + vec2(1, 0)), f.x), mix(hash12(i + vec2(0, 1)), hash12(i + vec2(1, 1)), f.x), f.y); } float vnoise3(vec3 p) { vec3 i = floor(p), f = fract(p); f = f * f * (3.0 - 2.0 * f); return mix(mix(mix(hash13(i), hash13(i + vec3(1, 0, 0)), f.x), mix(hash13(i + vec3(0, 1, 0)), hash13(i + vec3(1, 1, 0)), f.x), f.y), mix(mix(hash13(i + vec3(0, 0, 1)), hash13(i + vec3(1, 0, 1)), f.x), mix(hash13(i + vec3(0, 1, 1)), hash13(i + vec3(1, 1, 1)), f.x), f.y), f.z); } float fbm(vec2 p) { float a = 0.5, s = 0.0; for (int i = 0; i < 5; i++) { s += a * vnoise(p); p = mat2(1.6, 1.2, -1.2, 1.6) * p + 3.1; a *= 0.5; } return s; } float fbm3(vec3 p) { float a = 0.5, s = 0.0; for (int i = 0; i < 4; i++) { s += a * vnoise3(p); p = p * 2.03 + vec3(1.7, 9.2, 3.1); a *= 0.5; } return s; } // Clamp one sample before it is averaged: a single lucky glossy ray hitting the window would otherwise leave // a bright speck ("firefly") that takes hundreds of frames to fade. Call on the final colour in main(). vec3 clampSample(vec3 c, float m) { float l = max(c.r, max(c.g, c.b)); return l > m ? c * (m / l) : c; } // A new well-spread 2D random point per pixel AND per frame: the R2 low-discrepancy sequence over frames, // rotated by a per-pixel white-noise offset (structured offsets such as ign() show diagonal hatching while moving). // Use a different salt for every decision (pixel jitter, lens, sun disc, gloss...). Accumulation averages them. vec2 rand2(float salt) { vec2 f = gl_FragCoord.xy + salt * 17.13; return fract(vec2(hash12(f), hash12(f + 71.7)) + uFrame * vec2(0.7548776662, 0.5698402910)); }`; const GLSL_SAMPLING = ` mat3 basisOf(vec3 n) { vec3 t = abs(n.y) < 0.999 ? normalize(cross(vec3(0.0, 1.0, 0.0), n)) : vec3(1.0, 0.0, 0.0); return mat3(t, cross(n, t), n); } vec2 diskSample(vec2 u) { float r = sqrt(u.x), a = 6.2831853 * u.y; return r * vec2(cos(a), sin(a)); } vec3 cosineSample(vec3 n, vec2 u) { vec2 d = diskSample(u); return basisOf(n) * vec3(d, sqrt(max(0.0, 1.0 - dot(d, d)))); } // a microfacet normal from the GGX distribution: reflect about it for a rough reflection, refract through it for frosted glass vec3 ggxSample(vec3 n, float rough, vec2 u) { float a = rough * rough; float ct = sqrt((1.0 - u.x) / (1.0 + (a * a - 1.0) * u.x)), st = sqrt(max(0.0, 1.0 - ct * ct)), ph = 6.2831853 * u.y; return normalize(basisOf(n) * vec3(st * cos(ph), st * sin(ph), ct)); }`; const GLSL_CAMERA = ` // Thin-lens camera. Sub-pixel jitter = supersampling; a random point on the lens = true depth of field. // uAperture is the lens radius in scene units (0 = pinhole). uFocus is the distance along the view axis that is sharp. void cameraRay(out vec3 ro, out vec3 rd) { vec2 px = rand2(1.0) - 0.5; vec2 ndc = (gl_FragCoord.xy + px) / uRes * 2.0 - 1.0 - uShift; vec3 dir = normalize(uCamFw + uCamRt * (ndc.x * uTan * uAspect) + uCamUp * (ndc.y * uTan)); vec3 fp = uCamPos + dir * (uFocus / dot(dir, uCamFw)); vec2 lens = diskSample(rand2(2.0)) * uAperture; ro = uCamPos + uCamRt * lens.x + uCamUp * lens.y; rd = normalize(fp - ro); }`; // the light rig, edited for this scene: late low sun through a window on the left, raking along the wall const GLSL_RIG_SETTINGS = ` const vec3 KEY_DIR = normalize(vec3(-0.86, 0.42, 0.12)); const vec3 KEY_COL = vec3(1.0, 0.8, 0.6) * 1.15; const float KEY_SPREAD = 0.006; const float WIN_DIST = 150.0; const vec2 WIN_HALF = vec2(10.0, 15.0); const vec2 WIN_OFF = vec2(-6.0, 2.0); const float BAR = 0.7; const float BAR_Y = 4.0; const vec3 SKY_COL = vec3(0.58, 0.66, 0.78) * 0.14; const vec3 FILL_DIR = normalize(vec3(0.3, 0.42, 1.0)); const vec3 FILL_COL = vec3(1.0, 0.95, 0.88) * 0.1; const vec3 CEIL_COL = vec3(0.95, 0.9, 0.84) * 0.34;`; const GLSL_LIGHT_RIG = ` // the window opening with one vertical bar and one transom, in window-plane units float paneMask(vec2 q, float pen) { vec2 e = WIN_HALF - abs(q); float open = smoothstep(-pen, pen, e.x) * smoothstep(-pen, pen, e.y); float bars = smoothstep(-pen, pen, abs(q.x) - BAR) * smoothstep(-pen, pen, abs(q.y - BAR_Y) - BAR); return open * bars; } // The gobo: how much of the window a point sees along KEY_DIR. This is what makes light look like it came // from a real room instead of a CG directional light: a pool with straight edges and bar shadows. float keyGobo(vec3 p) { mat3 B = basisOf(KEY_DIR); vec2 q = vec2(dot(p, B[0]), dot(p, B[1])) - WIN_OFF; float d = max(WIN_DIST - dot(p, KEY_DIR), 1.0); return paneMask(q, 0.25 + d * KEY_SPREAD); } // What a mirror sees. The window appears as a bright shape with bars: that shape in every reflection is the // single strongest "this is a photograph" cue. Everything else is dark so reflections have contrast. // envStudioRough: the same room seen in a ROUGH surface. Instead of firing random glossy rays at a small, very // bright window (the source of sand-like speckle and sparkling metal), the window and card are blurred // analytically by the roughness. Deterministic: zero noise, converges in one frame. vec3 envStudioRough(vec3 rd, float rough) { float a = rough * rough; // GGX alpha: roughly the angular blur in radians vec3 c = mix(vec3(0.028, 0.025, 0.022), CEIL_COL, smoothstep(0.1 - a, 0.95 + a, rd.y)); c = mix(c, vec3(0.09, 0.075, 0.06), smoothstep(0.0, -0.5 - a, rd.y)); float k = dot(rd, KEY_DIR); if (k > 0.0) { mat3 B = basisOf(KEY_DIR); vec2 q = vec2(dot(rd, B[0]), dot(rd, B[1])) / k * WIN_DIST - WIN_OFF; float pen = 1.2 + a * WIN_DIST; // a blurred window spreads the same light over a larger area: keep its energy, so the peak drops float spread = (WIN_HALF.x * WIN_HALF.y) / ((WIN_HALF.x + pen) * (WIN_HALF.y + pen)); c += vec3(1.0, 0.96, 0.9) * 26.0 * paneMask(q, pen) * mix(1.0, spread, saturate(a * 4.0)); } float f = dot(rd, FILL_DIR); if (f > 0.0) { mat3 B = basisOf(FILL_DIR); vec2 e = vec2(0.6, 0.36) - abs(vec2(dot(rd, B[0]), dot(rd, B[1])) / f); float w = 0.18 + a; c += FILL_COL * 7.0 * smoothstep(-w, w, e.x) * smoothstep(-w, w, e.y); } return c; } vec3 envStudio(vec3 rd) { return envStudioRough(rd, 0.0); }`; const GLSL_MATERIALS = ` // q = position in the object's own frame, in CENTIMETRES (scale noise accordingly if your units differ). // n = geometric normal. Every material returns a perturbed normal: real surfaces are never perfect. struct Mat { vec3 albedo; float rough; float metal; float coat; vec3 n; }; Mat mk(vec3 a, float r, float m, float c, vec3 n) { Mat x; x.albedo = a; x.rough = r; x.metal = m; x.coat = c; x.n = n; return x; } // Metals: these are reflectance (F0) colours in linear light, not paint colours. const vec3 BRASS = vec3(0.88, 0.69, 0.37); const vec3 GOLD = vec3(1.0, 0.76, 0.33); const vec3 STEEL = vec3(0.56, 0.56, 0.54); const vec3 ALUMINIUM = vec3(0.91, 0.92, 0.92); const vec3 COPPER = vec3(0.95, 0.62, 0.50); // Brushed: fine parallel scratches along axis. Tilting the normal ACROSS the brushing stretches highlights // across it, which is how brushed metal really looks. Mat matBrushed(vec3 q, vec3 n, vec3 f0, vec3 axis) { vec3 b = normalize(cross(n, axis) + 1e-4); float a = dot(q, axis), c = dot(q, b); float s = 0.6 * vnoise(vec2(a * 0.5, c * 240.0)) + 0.4 * vnoise(vec2(a * 0.1, c * 700.0)); return mk(f0 * (0.96 + 0.04 * s), 0.24 + 0.04 * s, 1.0, 0.0, normalize(n + b * (s - 0.5) * 0.012)); } // Polished: near mirror, with faint handling haze in patches (no real polished object is uniform). Mat matPolished(vec3 q, vec3 n, vec3 f0) { float h = fbm(q.xz * 0.9 + q.y); return mk(f0, 0.04 + 0.09 * smoothstep(0.45, 0.75, h), 1.0, 0.0, n); } // Glazed ceramic: coloured body under a glass coat; glaze pools and thins, a few pinholes, gentle waviness. Mat matCeramic(vec3 q, vec3 n, vec3 glaze) { float pool = fbm(q.xz * 0.6 + q.y * 0.4); float pin = step(0.996, hash13(floor(q * 22.0))); vec3 w = vec3(fbm(q.xy * 1.3) - 0.5, 0.0, fbm(q.zy * 1.3 + 4.0) - 0.5); return mk(glaze * (0.78 + 0.4 * pool) * (1.0 - 0.6 * pin), 0.35, 0.0, 1.0, normalize(n + w * 0.025)); } // Matte paper or card: fibres, never flat white. Mat matPaper(vec3 q, vec3 n, vec3 tint) { float f = fbm(q.xz * 9.0) * 0.6 + vnoise(q.xz * 60.0) * 0.4; return mk(tint * (0.93 + 0.08 * f), 0.88, 0.0, 0.0, normalize(n + vec3(f - 0.5, 0.0, f - 0.5) * 0.02)); } // Linen: plain weave with slubs (thicker uneven threads), about 18 threads per cm. Mat matLinen(vec3 q, vec3 n, vec3 tint) { vec2 u = q.xz * 18.0; float wx = 0.5 + 0.5 * sin(u.x * PI), wy = 0.5 + 0.5 * sin(u.y * PI); float over = mod(floor(u.x) + floor(u.y), 2.0); float th = mix(wx, wy, over); float slub = vnoise(vec2(floor(u.x) * 3.1, u.y * 0.08)) * vnoise(vec2(u.x * 0.08, floor(u.y) * 2.7)); vec3 a = tint * (0.8 + 0.2 * th) * (0.92 + 0.16 * slub); return mk(a, 0.9, 0.0, 0.0, normalize(n + vec3(cos(u.x * PI) * (1.0 - over), 0.0, cos(u.y * PI) * over) * 0.08)); } // Plaster / limewash: broad trowel clouds and fine pores. Mat matPlaster(vec3 q, vec3 n, vec3 tint) { float c = fbm(q.xy * 0.18 + q.z * 0.1), p = vnoise(q.xy * 35.0 + q.z); return mk(tint * (0.86 + 0.22 * c) * (0.97 + 0.04 * p), 0.92, 0.0, 0.0, normalize(n + vec3(p - 0.5, c - 0.5, 0.0) * 0.03)); } // Honed travertine: cream with soft bands along one direction and long shallow pits. Mat matTravertine(vec3 q, vec3 n) { float band = fbm(vec2(q.z * 0.35 + fbm(q.xz * 0.08) * 2.0, q.x * 0.03)); vec3 a = mix(vec3(0.66, 0.58, 0.47), vec3(0.78, 0.71, 0.6), band); float pitN = vnoise(vec2(q.x * 1.6, q.z * 9.0) + 7.0) * vnoise(vec2(q.x * 0.5, q.z * 3.0)); float pit = smoothstep(0.5, 0.58, pitN); a = mix(a, vec3(0.52, 0.44, 0.34), pit * 0.3); a *= 0.96 + 0.08 * vnoise(q.xz * 30.0); return mk(a, mix(0.42, 0.9, pit), 0.0, 0.0, normalize(n + vec3(0.0, 0.0, pit * 0.08))); } // Marble: soft warped veins, polished. Mat matMarble(vec3 q, vec3 n, vec3 base, vec3 vein) { // thin veins that wander but do not curl: low warp, a main vein family and a fainter hairline family float w = fbm3(q * 0.15) * 3.2; float v = 1.0 - smoothstep(0.0, 0.05, abs(sin(q.x * 0.35 + q.z * 0.18 + w))); float hair = 1.0 - smoothstep(0.0, 0.03, abs(sin(q.x * 0.9 - q.z * 0.6 + w * 1.7))); vec3 a = mix(base, vein, v * 0.6 + hair * 0.2) * (0.96 + 0.08 * fbm(q.xz * 1.5)); return mk(a, 0.12, 0.0, 0.6, n); } // Wood, grain running along x. Photographic wood is LOW contrast: rings within 25% brightness, not stripes. const vec3 OAK_LIGHT = vec3(0.52, 0.36, 0.20), OAK_DARK = vec3(0.36, 0.23, 0.12); const vec3 WALNUT_LIGHT = vec3(0.20, 0.11, 0.06), WALNUT_DARK = vec3(0.11, 0.055, 0.03); Mat matWood(vec3 q, vec3 n, vec3 light, vec3 dark, float pores) { float r = length(q.yz + vec2(9.0, 4.0)) * 3.2 + fbm3(q * vec3(0.05, 0.7, 0.7)) * 3.0; float ring = smoothstep(0.4, 0.95, fract(r)); float streak = vnoise(vec2(q.x * 0.05, q.z * 11.0 + q.y * 11.0)) * 0.6 + vnoise(vec2(q.x * 0.2, q.z * 40.0)) * 0.4; vec3 a = mix(light, dark, ring * 0.3 + streak * 0.35); float pore = smoothstep(0.78, 0.86, vnoise(vec2(q.x * 1.4, (q.z + q.y) * 55.0))) * pores; a *= 1.0 - pore * 0.35; return mk(a, 0.45 + 0.2 * pore, 0.0, 0.35, normalize(n + vec3(0.0, 0.0, (streak - 0.5) * 0.03))); } // Dielectrics (glass, acrylic, resin). You trace the refracted ray yourself; these do the physics around it. float fresnelD(float c, float ior) { float r = (1.0 - ior) / (1.0 + ior); r *= r; return r + (1.0 - r) * pow(1.0 - saturate(c), 5.0); } // Light lost to the colour of the body over a path of length len. absorb is per unit length per channel: // clear soda glass vec3(0.05, 0.012, 0.03) per cm (green edges); resin uses strong values for deep colour. vec3 beer(vec3 absorb, float len) { return exp(-absorb * len); }`; const GLSL_SDF = ` float sdRoundBox(vec3 p, vec3 b, float r) { vec3 q = abs(p) - b + r; return length(max(q, 0.0)) + min(max(q.x, max(q.y, q.z)), 0.0) - r; } float smax(float a, float b, float k) { float h = max(k - abs(a - b), 0.0); return max(a, b) + h * h * 0.25 / k; } float smin(float a, float b, float k) { float h = max(k - abs(a - b), 0.0); return min(a, b) - h * h * 0.25 / k; } // ray vs box centred at the origin: (t near, t far) vec2 boxI(vec3 ro, vec3 rd, vec3 b) { rd = mix(rd, vec3(1e-5), lessThan(abs(rd), vec3(1e-5))); vec3 m = 1.0 / rd, n = m * ro, k = abs(m) * b; vec3 t1 = -n - k, t2 = -n + k; return vec2(max(max(t1.x, t1.y), t1.z), min(min(t2.x, t2.y), t2.z)); } vec3 boxFaceNormal(vec3 p, vec3 b) { vec3 d = abs(p) / b; return d.x > d.y && d.x > d.z ? vec3(sign(p.x), 0, 0) : d.y > d.z ? vec3(0, sign(p.y), 0) : vec3(0, 0, sign(p.z)); }`; const GLSL_SHADOW_AO = ` // needs: const float SCENE_TOP, AO_RADIUS; float map(vec3); float mapShadow(vec3); vec3 lightFilter(vec3 p, vec3 l) // Deterministic penumbra (no random sun points: random shadow rays are the main source of floor speckle). // SHADOW_SOFT is the penumbra angle in radians: sun-sharp is ~0.01, overcast-soft ~0.08. const float SHADOW_SOFT = 0.03; float softShadow(vec3 ro, vec3 rd, float tmin, float tmax) { float res = 1.0, t = tmin, ph = 1e10; for (int i = 0; i < 48; i++) { vec3 p = ro + rd * t; if (p.y > SCENE_TOP && rd.y > 0.0) break; float h = mapShadow(p); if (h < 0.0004) return 0.0; float y = h * h / (2.0 * ph), d = sqrt(max(h * h - y * y, 0.0)); res = min(res, d / (SHADOW_SOFT * max(1e-3, t - y))); ph = h; t += clamp(h, 0.01, 3.0); if (t > tmax) break; } res = saturate(res); return res * res * (3.0 - 2.0 * res); } vec3 shadowCol(vec3 ro, vec3 rd) { return softShadow(ro, rd, 0.01, 200.0) * lightFilter(ro, rd); } float calcAO(vec3 p, vec3 n) { float occ = 0.0, s = 1.0; for (int i = 0; i < 5; i++) { float h = AO_RADIUS * (0.06 + 0.94 * float(i) / 4.0); occ += (h - map(p + n * h)) * s; s *= 0.72; } return saturate(1.0 - 1.4 * occ / AO_RADIUS); } vec3 calcNormal(vec3 p, float e) { vec2 k = vec2(1.0, -1.0); return normalize(k.xyy * map(p + k.xyy * e) + k.yyx * map(p + k.yyx * e) + k.yxy * map(p + k.yxy * e) + k.xxx * map(p + k.xxx * e)); }`; const GLSL_LIGHTING = ` // One opaque surface under the rig. Diffuse from the key (through the window gobo, with smooth analytic // shadows), cool sky and the card; specular reflects the room along the mirror direction with the window // pre-blurred by roughness (envStudioRough). Everything here is deterministic, so it adds NO per-frame noise: // accumulation only has to clean up edges, depth of field and any glass you trace yourself. // coat adds a sharp glaze/lacquer layer. vec3 litOpaque(vec3 p, vec3 v, Mat m, float ao) { vec3 n = m.n; float NoV = max(dot(n, v), 1e-3); vec3 L = KEY_DIR; float NoL = max(dot(n, L), 0.0); vec3 sun = NoL > 0.0 ? KEY_COL * NoL * keyGobo(p) * shadowCol(p + n * 0.015, L) : vec3(0.0); vec3 f0 = mix(vec3(0.04), m.albedo, m.metal); vec3 F = f0 + (1.0 - f0) * pow(1.0 - NoV, 5.0); vec3 amb = SKY_COL * (0.55 + 0.45 * n.y) + FILL_COL * 1.6 * max(dot(n, FILL_DIR) + 0.25, 0.0); vec3 col = (1.0 - F) * (1.0 - m.metal) * m.albedo * (sun + amb * ao); vec3 r = reflect(-v, n); // rough surfaces lose some of the grazing Fresnel boost vec3 Fr = f0 + (max(vec3(1.0 - m.rough), f0) - f0) * pow(1.0 - NoV, 5.0); col += Fr * envStudioRough(r, m.rough) * mix(vec3(1.0), shadowCol(p + n * 0.015, r), 1.0 - m.rough * 0.6) * mix(1.0, ao, 0.6); if (m.coat > 0.0) { vec3 rc = reflect(-v, n); float Fc = (0.04 + 0.96 * pow(1.0 - NoV, 5.0)) * m.coat; col = col * (1.0 - Fc) + Fc * envStudio(rc) * shadowCol(p + n * 0.015, rc); } return col; } // Light that a lit translucent body gives off from inside (resin, wax, jade, frosted acrylic). vec3 subsurface(vec3 p, vec3 n, vec3 scatterCol, float strength) { return scatterCol * strength * (KEY_COL * keyGobo(p) * (0.35 + 0.65 * max(dot(n, KEY_DIR), 0.0)) + SKY_COL); }`; const OUTPUT_FS = `#version 300 es precision highp float; uniform sampler2D uAccum; uniform vec2 uPx; uniform float uExposure, uGrain, uVignette, uSeed, uHalation; in vec2 vUv; out vec4 o; float ign(vec2 p) { return fract(52.9829189 * fract(dot(p, vec2(0.06711056, 0.00583715)))); } float hash(vec2 p) { vec3 p3 = fract(vec3(p.xyx) * 0.1031); p3 += dot(p3, p3.yzx + 33.33); return fract((p3.x + p3.y) * p3.z); } // ACES filmic fit: highlights roll off instead of clipping, which is most of the "camera" look vec3 aces(vec3 x) { return clamp((x * (2.51 * x + 0.03)) / (x * (2.43 * x + 0.59) + 0.14), 0.0, 1.0); } void main() { vec3 c = texture(uAccum, vUv).rgb; // halation: the brightest highlights bleed a warm glow, like light scattering in film vec3 g = vec3(0.0); float rot = 6.2831853 * ign(gl_FragCoord.xy); for (int k = 0; k < 12; k++) { float a = float(k) * 2.39996 + rot, r = 2.0 + 24.0 * sqrt(float(k) / 12.0); g += max(texture(uAccum, vUv + vec2(cos(a), sin(a)) * r * uPx).rgb - 2.0, 0.0); } c += g / 12.0 * vec3(0.42, 0.3, 0.22) * uHalation; c = aces(c * uExposure); vec2 q = vUv - 0.5; c *= 1.0 - uVignette * dot(q, q) * 2.0; c = pow(c, vec3(1.0 / 2.2)); // grain lives in the midtones, never in pure black or white float l = dot(c, vec3(0.299, 0.587, 0.114)); // static grain (it does not crawl), meant to be barely visible: default amplitude 0.012 c += (hash(gl_FragCoord.xy + uSeed) - 0.5) * uGrain * (0.25 + 3.0 * l * (1.0 - l)); o = vec4(c, 1.0); }`; type Vec3 = [number, number, number]; type Camera = { pos: Vec3; rt: Vec3; up: Vec3; fw: Vec3; tan: number; aspect: number; shift: [number, number]; aperture: number; focus: number }; const sub = (a: Vec3, b: Vec3): Vec3 => [a[0] - b[0], a[1] - b[1], a[2] - b[2]]; const dot = (a: Vec3, b: Vec3) => a[0] * b[0] + a[1] * b[1] + a[2] * b[2]; const norm = (a: Vec3): Vec3 => { const l = Math.hypot(a[0], a[1], a[2]) || 1; return [a[0] / l, a[1] / l, a[2] / l]; }; const cross = (a: Vec3, b: Vec3): Vec3 => [a[1] * b[2] - a[2] * b[1], a[2] * b[0] - a[0] * b[2], a[0] * b[1] - a[1] * b[0]]; function lookAt(pos: Vec3, target: Vec3, fovYdeg: number, aspect: number, aperture = 0, shift: [number, number] = [0, 0]): Camera { const fw = norm(sub(target, pos)); const rt = norm(cross(fw, [0, 1, 0])); const up = cross(rt, fw); return { pos, rt, up, fw, tan: Math.tan((fovYdeg * Math.PI) / 360), aspect, shift, aperture, focus: Math.hypot(...sub(target, pos)) }; } function compileProgram(gl: WebGL2RenderingContext, vs: string, fs: string) { const p = gl.createProgram()!; for (const [type, src] of [[gl.VERTEX_SHADER, vs], [gl.FRAGMENT_SHADER, fs]] as const) { 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) || "shader"); gl.attachShader(p, s); } gl.linkProgram(p); if (!gl.getProgramParameter(p, gl.LINK_STATUS)) throw new Error(gl.getProgramInfoLog(p) || "link"); return p; } type StageOptions = { canvas: HTMLCanvasElement; wrap: HTMLElement; /** full fragment shader: GLSL_HEADER + chunks + your scene. Writes linear HDR to `o`. */ sceneFS: string; /** called once per CSS resize, before drawing: build your camera here and return it */ camera: (cssW: number, cssH: number) => Camera; /** your uniforms, every rendered frame (program is in use) */ uniforms?: (gl: WebGL2RenderingContext, loc: (name: string) => WebGLUniformLocation | null, t: number) => void; /** advance your simulation; return true while anything visible is still moving */ step?: (dt: number, t: number) => boolean; /** samples per pixel when at rest (then drawing stops). Default 128; never below 96 */ samples?: number; /** blend weight of each new frame while moving: 0.25 (default) keeps ~4 frames of history; raise for fast motion */ motionBlend?: number; maxPixels?: number; // cap on drawing buffer pixels, default 2.2e6 maxDpr?: number; // default 2 exposure?: number; grain?: number; vignette?: number; halation?: number; onFail?: () => void; // WebGL 2 missing, shader error or context lost: show your CSS still }; function createPhotoStage(o: StageOptions) { const { canvas, wrap } = o; const fail = () => { o.onFail?.(); return null; }; const gl = canvas.getContext("webgl2", { antialias: false, alpha: false, depth: false, powerPreference: "high-performance" }); if (!gl) return fail(); const float = !!gl.getExtension("EXT_color_buffer_float"); let scene: WebGLProgram, out: WebGLProgram; try { scene = compileProgram(gl, FULLSCREEN_VS, o.sceneFS); out = compileProgram(gl, FULLSCREEN_VS, OUTPUT_FS); } catch (e) { console.error(e); return fail(); } const SAMPLES = o.samples ?? 128; const MOTION = o.motionBlend ?? 0.25; let frameNo = 0; const maxPixels = o.maxPixels ?? 2.2e6; let scale = Math.min(window.devicePixelRatio || 1, o.maxDpr ?? 2); const vao = gl.createVertexArray(); const fbo = gl.createFramebuffer(); const tex = gl.createTexture(); const locS = new Map(); const loc = (n: string) => { if (!locS.has(n)) locS.set(n, gl.getUniformLocation(scene, n)); return locS.get(n)!; }; const locO = (n: string) => gl.getUniformLocation(out, n); let W = 0, H = 0, cssW = 1, cssH = 1, n = 0, cam: Camera | null = null; const resize = () => { cssW = Math.max(1, wrap.clientWidth); cssH = Math.max(1, wrap.clientHeight); let k = scale; if (cssW * cssH * k * k > maxPixels) k = Math.sqrt(maxPixels / (cssW * cssH)); cam = o.camera(cssW, cssH); n = 0; const w = Math.max(2, Math.round(cssW * k)), h = Math.max(2, Math.round(cssH * k)); if (w === W && h === H) return; W = w; H = h; canvas.width = W; canvas.height = H; gl.bindTexture(gl.TEXTURE_2D, tex); gl.texImage2D(gl.TEXTURE_2D, 0, float ? gl.RGBA16F : gl.RGBA8, W, H, 0, gl.RGBA, float ? gl.HALF_FLOAT : gl.UNSIGNED_BYTE, null); gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR); gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR); gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE); gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE); gl.bindFramebuffer(gl.FRAMEBUFFER, fbo); gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0); }; const draw = (t: number, moving: boolean) => { const c = cam!; gl.bindVertexArray(vao); gl.viewport(0, 0, W, H); gl.bindFramebuffer(gl.FRAMEBUFFER, fbo); gl.useProgram(scene); gl.uniform2f(loc("uRes"), W, H); gl.uniform1f(loc("uFrame"), frameNo++); // never repeats, so moving frames keep exploring new samples gl.uniform1f(loc("uTime"), t); gl.uniform3fv(loc("uCamPos"), c.pos); gl.uniform3fv(loc("uCamRt"), c.rt); gl.uniform3fv(loc("uCamUp"), c.up); gl.uniform3fv(loc("uCamFw"), c.fw); gl.uniform1f(loc("uTan"), c.tan); gl.uniform1f(loc("uAspect"), c.aspect); gl.uniform1f(loc("uAperture"), c.aperture); gl.uniform1f(loc("uFocus"), c.focus); gl.uniform2fv(loc("uShift"), c.shift); o.uniforms?.(gl, loc, t); // blend the new jittered frame into the running average: alpha 1/(n+1) is an exact mean; // while moving keep a SHORT history instead of restarting: alpha 0.25 is about 4 frames (a touch of motion // blur, no speckle). When it stops, carry on averaging from there: n continues at 1/MOTION samples. const alpha = moving ? MOTION : 1 / (n + 1); gl.enable(gl.BLEND); gl.blendFunc(gl.CONSTANT_ALPHA, gl.ONE_MINUS_CONSTANT_ALPHA); gl.blendColor(0, 0, 0, n === 0 ? 1 : alpha); gl.drawArrays(gl.TRIANGLES, 0, 3); gl.disable(gl.BLEND); gl.bindFramebuffer(gl.FRAMEBUFFER, null); gl.useProgram(out); gl.activeTexture(gl.TEXTURE0); gl.bindTexture(gl.TEXTURE_2D, tex); gl.uniform1i(locO("uAccum"), 0); gl.uniform2f(locO("uPx"), 1 / W, 1 / H); gl.uniform1f(locO("uExposure"), o.exposure ?? 1); gl.uniform1f(locO("uGrain"), o.grain ?? 0.012); gl.uniform1f(locO("uVignette"), o.vignette ?? 0.35); gl.uniform1f(locO("uHalation"), o.halation ?? 0.6); gl.uniform1f(locO("uSeed"), 0); gl.drawArrays(gl.TRIANGLES, 0, 3); n = moving ? Math.round(1 / MOTION) : n + 1; }; resize(); const ro = new ResizeObserver(resize); ro.observe(wrap); let raf = 0, last = performance.now(), slow = 0, onScreen = true, dead = false; const t0 = last; const tick = (now: number) => { raf = 0; const real = now - last; last = now; const dt = Math.min(real / 1000, 0.05); const t = (now - t0) / 1000; const moving = o.step ? o.step(dt, t) : false; if (moving || n < SAMPLES) { if (moving) { // measure, do not guess: if moving frames run long, draw fewer pixels slow = slow * 0.9 + (real > 28 ? 0.1 : 0); if (slow > 0.55 && scale > 0.45) { scale *= 0.85; slow = 0; W = 0; resize(); } } draw(t, moving); } if (onScreen && !document.hidden) raf = requestAnimationFrame(tick); }; const wake = () => { if (!raf && !dead && onScreen && !document.hidden) { last = performance.now(); raf = requestAnimationFrame(tick); } }; const io = new IntersectionObserver(([e]) => { onScreen = e.isIntersecting; wake(); }); io.observe(wrap); document.addEventListener("visibilitychange", wake); const lost = (e: Event) => { e.preventDefault(); dead = true; o.onFail?.(); }; canvas.addEventListener("webglcontextlost", lost); wake(); return { /** something changed that is not animated (theme, text, reduced-motion snap): restart accumulation */ invalidate() { n = 0; wake(); }, /** call after step() starts moving from rest (input), so the loop is running */ wake, camera: () => cam!, size: () => [cssW, cssH] as const, dispose() { dead = true; cancelAnimationFrame(raf); ro.disconnect(); io.disconnect(); document.removeEventListener("visibilitychange", wake); canvas.removeEventListener("webglcontextlost", lost); gl.getExtension("WEBGL_lose_context")?.loseContext(); }, }; } function springStep(s: { x: number; v: number }, target: number, dt: number, k = 900, damping = 38) { const sub = Math.max(1, Math.ceil(dt / 0.004)); for (let i = 0; i < sub; i++) { const h = dt / sub; s.v += (k * (target - s.x) - damping * s.v) * h; s.x += s.v * h; } if (Math.abs(s.v) < 0.02 && Math.abs(target - s.x) < 0.002) { s.x = target; s.v = 0; return false; } return true; } const STILL_GRAIN = "url(\"data:image/svg+xml;utf8,\")"; /* ---- end of kit ---- */ // The scene, in centimetres: an opal glass globe lamp on a brass collar, on a walnut table, against a painted // plaster wall. The bulb sits at the centre of the globe; uGlow (0 to 1) is how bright it burns. const SCENE = ` const float SCENE_TOP = 40.0; const float AO_RADIUS = 2.4; uniform float uGlow; const vec3 GC = vec3(0.0, 11.2, 0.0); const float GR = 8.0; const float WALL_Z = -26.0; const vec3 LAMP = vec3(1.0, 0.6, 0.3); float sdCyl(vec3 p, float r, float h, float e) { vec2 d = vec2(length(p.xz) - r + e, abs(p.y) - h + e); return min(max(d.x, d.y), 0.0) + length(max(d, 0.0)) - e; } float brass(vec3 p) { float foot = sdCyl(p - vec3(0.0, 0.32, 0.0), 5.4, 0.32, 0.14); float neck = sdCyl(p - vec3(0.0, 2.0, 0.0), 2.3, 1.6, 0.2); float cup = sdCyl(p - vec3(0.0, 3.85, 0.0), 3.6, 0.5, 0.2); return smin(smin(foot, neck, 0.6), cup, 0.5); } vec2 scene(vec3 p, int skip) { vec2 r = vec2(p.y, 0.0); float w = p.z - WALL_Z; if (w < r.x) r = vec2(w, 1.0); float b = brass(p); if (b < r.x) r = vec2(b, 2.0); if (skip != 3) { float g = length(p - GC) - GR; if (g < r.x) r = vec2(g, 3.0); } return r; } float map(vec3 p) { return scene(p, -1).x; } // the window is imagined in the left wall, so the back wall does not block the sun float mapShadow(vec3 p) { return min(brass(p), length(p - GC) - GR); } vec3 lightFilter(vec3 p, vec3 l) { return vec3(1.0); } `; const SCENE_MAIN = ` // Light from the globe onto the table, the wall and the brass: a large warm source, so a broad wrap and a // soft shadow from the collar. Deterministic, no sampling. vec3 lampLight(vec3 p, vec3 n, vec3 v, Mat m) { if (uGlow <= 0.0) return vec3(0.0); vec3 d = GC - p; float dist = length(d); vec3 l = d / dist; float wrap = saturate((dot(n, l) + 0.35) / 1.35); float fall = 1.0 / (dist * dist * 0.012 + 0.35); // only the collar can hide the globe; stop the shadow ray before it reaches the glass float sh = 1.0, t = 0.05; for (int i = 0; i < 28; i++) { float h = brass(p + l * t); sh = min(sh, 6.0 * h / t); t += clamp(h, 0.05, 2.0); if (t > dist - GR * 0.7 || sh < 0.0) break; } sh = saturate(sh); vec3 E = LAMP * uGlow * 14.0 * fall * smoothstep(0.0, 1.0, sh); vec3 f0 = mix(vec3(0.04), m.albedo, m.metal); vec3 h = normalize(l + v); float spec = pow(max(dot(m.n, h), 0.0), mix(400.0, 8.0, m.rough)) * mix(1.0, 0.25, m.rough); return E * ((1.0 - m.metal) * m.albedo * wrap + f0 * spec * max(dot(m.n, l), 0.0) * 6.0); } vec3 shadeGlobe(vec3 p, vec3 v, vec3 n) { vec3 q = p - GC; // acid-etched opal glass: a milky body with a soft gloss, a slow cloud in the etch float etch = fbm(q.xy * 0.9 + q.z * 0.4); Mat m = mk(vec3(0.82, 0.81, 0.78) * (0.95 + 0.1 * etch), 0.55, 0.0, 0.55, normalize(n + vec3(etch - 0.5) * 0.02)); vec3 col = litOpaque(p, v, m, 1.0) * 0.7 + subsurface(p, n, vec3(0.92, 0.9, 0.86), 0.22); // the burning bulb: light scattered through the opal, a touch brighter where we look through the most glass float NoV = saturate(dot(n, v)); float lower = smoothstep(-GR, -GR * 0.35, q.y); // the brass cup hides the bottom of the globe float core = exp(-pow(length(q - dot(q, v) * v) / GR, 2.0) * 2.2); // the bulb seen through the frost float g = uGlow * uGlow * 0.6 + uGlow * 0.4; vec3 glow = LAMP * g * (1.1 * (0.18 + 0.82 * pow(NoV, 1.3)) + 1.5 * core * core) * (0.94 + 0.12 * etch) * mix(0.35, 1.0, lower); return col * (1.0 - 0.5 * uGlow) + glow; } vec3 shadeOpaque(int id, vec3 p, vec3 v) { vec3 n = calcNormal(p, 0.003); float ao = calcAO(p, n); Mat m; if (id == 0) m = matWood(p.zyx, n, vec3(0.24, 0.135, 0.075), WALNUT_DARK * 1.3, 1.0); else if (id == 1) m = matPlaster(p, n, vec3(0.055, 0.095, 0.13)); else { m = matBrushed(p, n, BRASS * 0.92, vec3(1.0, 0.0, 0.0)); m.rough = 0.34; } return litOpaque(p, v, m, ao) + lampLight(p, n, v, m) * mix(1.0, ao, 0.5); } void main() { vec3 ro, rd; cameraRay(ro, rd); float t = 0.0; vec2 h = vec2(1e9, 0.0); bool hit = false; for (int s = 0; s < 200; s++) { h = scene(ro + rd * t, -1); if (h.x < 0.0003 * t) { hit = true; break; } t += h.x; if (t > 1200.0) break; } vec3 p = ro + rd * t, col; int id = int(h.y + 0.5); if (!hit) col = envStudio(rd); else if (id == 3) col = shadeGlobe(p, -rd, normalize(p - GC)); else col = shadeOpaque(id, p, -rd); o = vec4(clampSample(col, 5.0), 1.0); } `; const SCENE_FS = [GLSL_HEADER, GLSL_COMMON, GLSL_SAMPLING, GLSL_CAMERA, GLSL_RIG_SETTINGS, GLSL_LIGHT_RIG, GLSL_MATERIALS, GLSL_SDF, SCENE, GLSL_SHADOW_AO, GLSL_LIGHTING, SCENE_MAIN].join("\n"); const glowFor = (count: number) => (count === 0 ? 0 : Math.min(1, GLOW_FIRST + GLOW_STEP * (count - 1))); /** The lamp. Purely decorative: the accordion beside it is the real control. */ function Lamp({ glow }: { glow: number }) { const reduce = useReducedMotion(); const wrapRef = useRef(null); const canvasRef = useRef(null); const [still, setStill] = useState(false); const sim = useRef({ glow: { x: glow, v: 0 }, target: glow, wake: () => {} }); useEffect(() => { sim.current.target = glow; sim.current.wake(); }, [glow]); useEffect(() => { const wrap = wrapRef.current, canvas = canvasRef.current; if (!wrap || !canvas) return; const s = sim.current; const stage = createPhotoStage({ canvas, wrap, sceneFS: SCENE_FS, samples: 128, exposure: 1.05, vignette: 0.4, motionBlend: 0.3, onFail: () => setStill(true), camera: (w, h) => { const aspect = w / h; const fov = 17; const el = 0.44; const target: Vec3 = [0, 8.6, 0]; const fitH = 21.0 / Math.tan((fov * Math.PI) / 360); // the lamp and some table, top to bottom const fitW = 15 / (Math.tan((fov * Math.PI) / 360) * aspect); // and across, on wide short frames const dist = Math.max(fitH, fitW); return lookAt([dist * 0.18, target[1] + Math.sin(el) * dist, Math.cos(el) * dist], target, fov, aspect, dist * 0.012, [0, -0.04]); }, uniforms: (gl, loc) => gl.uniform1f(loc("uGlow"), Math.max(0, s.glow.x)), // a filament warms up and cools down; it never snaps (unless motion is reduced) step: (dt) => { if (reduce) { if (s.glow.x === s.target) return false; s.glow.x = s.target; s.glow.v = 0; return true; } return springStep(s.glow, s.target, dt, 26, 10); }, }); if (!stage) return; s.wake = () => stage.wake(); return () => { s.wake = () => {}; stage.dispose(); }; }, [reduce]); return (