From ff8a37cf195f340ced82f572552d2a796a5441cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miguel=20=C3=81ngel?= <miguel.sierra@heygen.com>
Date: Sat, 8 Aug 2026 16:21:04 +0000
Subject: [PATCH] feat(registry): add the gallery-tunnel depth block

A square corridor receding to a vanishing point, its faces tiled with
colour slabs and images that swell toward camera and pass. Depth is the
catalog's largest gap, and this is the only depth move whose panels are
content slots, so it carries a shot rather than decorating one.

Everything keys off one integer: the absolute segment number in a pool
slot at the current distance. Rhythm, visibility, colour and image choice
all derive from a hash of that number, so a segment carries identical
panels however it is scrubbed to. The reference's sequential colour and
image counters are gone, along with its camera-chase lerp, which under a
constant rate only contributed a fixed lag.

The recycle boundary is derived from the fog distance rather than
duplicated, so a segment reappears exactly where fog reaches the backdrop
and moving the fog moves the boundary with it. Verified on a zoom crop
across several recycle events: slabs emerge from black and brighten
monotonically, nothing pops in.

Two bugs surfaced while building it. Composition variables are read from
the authored attribute rather than the runtime bag, which is undefined
when an inline script runs and silently resolved every string variable to
empty. And image panels are laid out at natural size inside a clipped
well, because a CSS-sized img uploads a 1x1 texture: the browser samples
the laid-out size, not the natural one.
---
 docs/catalog/blocks/gallery-tunnel.mdx        |  58 +++
 docs/docs.json                                |   1 +
 docs/public/catalog-index.json                |  16 +
 .../blocks/gallery-tunnel/gallery-tunnel.html | 454 ++++++++++++++++++
 .../blocks/gallery-tunnel/registry-item.json  | 101 ++++
 registry/registry.json                        |   4 +
 6 files changed, 634 insertions(+)
 create mode 100644 docs/catalog/blocks/gallery-tunnel.mdx
 create mode 100644 registry/blocks/gallery-tunnel/gallery-tunnel.html
 create mode 100644 registry/blocks/gallery-tunnel/registry-item.json

diff --git a/docs/catalog/blocks/gallery-tunnel.mdx b/docs/catalog/blocks/gallery-tunnel.mdx
new file mode 100644
index 0000000000..f0c1c46735
--- /dev/null
+++ b/docs/catalog/blocks/gallery-tunnel.mdx
@@ -0,0 +1,58 @@
+---
+title: "Gallery Tunnel"
+description: "An infinite corridor of panels: a square tunnel receding to a vanishing point, its floor, ceiling and walls tiled with saturated colour slabs and caller-supplied images that swell toward camera and exit past you, the far end dissolving into fog."
+---
+
+<video className="w-full aspect-video rounded-xl object-cover bg-zinc-100 dark:bg-zinc-800" src="https://static.heygen.ai/hyperframes-oss/docs/images/catalog/blocks/gallery-tunnel.mp4" poster="https://static.heygen.ai/hyperframes-oss/docs/images/catalog/blocks/gallery-tunnel.png" autoPlay muted loop playsInline />
+
+## Install
+
+```bash Terminal
+npx hyperframes add gallery-tunnel
+```
+
+That writes one file: `compositions/gallery-tunnel.html`.
+
+## Add it to your video
+
+It runs for 12 seconds at 1920×1080. Paste this into your composition:
+
+```html index.html
+<div
+  data-composition-id="gallery-tunnel"
+  data-composition-src="compositions/gallery-tunnel.html"
+  data-start="0"
+  data-duration="12"
+  data-track-index="1"
+  data-width="1920"
+  data-height="1080"
+></div>
+```
+
+Move it in time with `data-start`. Put it on a different timeline row with
+`data-track-index`. See [data attributes](/concepts/data-attributes) for the rest.
+
+## Change how it looks
+
+Set these CSS variables on the block:
+
+- `--images` — Image slots: comma-separated paths, tiled into the panels (e.g. assets/shot-1.png,assets/shot-2.png). Defaults to ``.
+- `--imagemix` — Image share of filled slots (0 = all colour, 1 = all images). Defaults to `0.5`.
+- `--speed` — Flight speed (segments per second). Defaults to `3`.
+- `--palette` — Slab palette: comma-separated hex colours. Defaults to `#FF6A00,#AB54F7,#EA3737,#0072E3,#00AA3C,#FFB200`.
+- `--grid` — Grid density: slots per wall face per axis (2 = 4 per face, 16 per segment). Defaults to `2`.
+- `--fill` — Slot fill rate. Defaults to `0.5`.
+- `--fog` — Fog distance in segments: depth at which the corridor reaches pure backdrop. Defaults to `14.25`.
+- `--edgecolor` — Edge line colour. Defaults to `#B0B0B0`.
+- `--edgeopacity` — Edge line opacity. Defaults to `0.5`.
+- `--backdrop` — Backdrop and fog colour. Defaults to `#000000`.
+
+{/* hf:generated-footer */}
+
+Tagged `webgl` `3d` `background` `showcase` `depth` `loop`.
+
+## Related topics
+
+- [Browse the complete Catalog](/catalog)
+- [Add assets and Catalog items in Studio](/studio/assets-and-blocks)
+- [Build a richer composition](/go-further)
diff --git a/docs/docs.json b/docs/docs.json
index c51c359780..53c1d5d3e8 100644
--- a/docs/docs.json
+++ b/docs/docs.json
@@ -405,6 +405,7 @@
               "catalog/blocks/code-snippet-solarized-light",
               "catalog/blocks/code-snippet-visual-studio-dark",
               "catalog/blocks/code-snippet-visual-studio-light",
+              "catalog/blocks/gallery-tunnel",
               "catalog/blocks/north-korea-locked-down",
               "catalog/blocks/nyc-paris-flight",
               "catalog/blocks/ui-3d-reveal",
diff --git a/docs/public/catalog-index.json b/docs/public/catalog-index.json
index 8255b52d5e..7a13401dc2 100644
--- a/docs/public/catalog-index.json
+++ b/docs/public/catalog-index.json
@@ -921,6 +921,22 @@
     "href": "/catalog/blocks/freeze-frame-dressing",
     "preview": "https://static.heygen.ai/hyperframes-oss/docs/images/catalog/blocks/freeze-frame-dressing.png"
   },
+  {
+    "name": "gallery-tunnel",
+    "type": "block",
+    "title": "Gallery Tunnel",
+    "description": "An infinite corridor of panels: a square tunnel receding to a vanishing point, its floor, ceiling and walls tiled with saturated colour slabs and caller-supplied images that swell toward camera and exit past you, the far end dissolving into fog.",
+    "tags": [
+      "webgl",
+      "3d",
+      "background",
+      "showcase",
+      "depth",
+      "loop"
+    ],
+    "href": "/catalog/blocks/gallery-tunnel",
+    "preview": "https://static.heygen.ai/hyperframes-oss/docs/images/catalog/blocks/gallery-tunnel.png"
+  },
   {
     "name": "glitch",
     "type": "block",
diff --git a/registry/blocks/gallery-tunnel/gallery-tunnel.html b/registry/blocks/gallery-tunnel/gallery-tunnel.html
new file mode 100644
index 0000000000..82b2d766e8
--- /dev/null
+++ b/registry/blocks/gallery-tunnel/gallery-tunnel.html
@@ -0,0 +1,454 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=1920, height=1080" />
+    <title>Gallery Tunnel</title>
+    <script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js"></script>
+    <script src="https://cdn.jsdelivr.net/npm/three@0.147.0/build/three.min.js"></script>
+    <style>
+      *,
+      *::before,
+      *::after {
+        margin: 0;
+        padding: 0;
+        box-sizing: border-box;
+      }
+      body {
+        background: #000;
+        overflow: hidden;
+      }
+      #gt-root {
+        position: relative;
+        width: 1920px;
+        height: 1080px;
+        overflow: hidden;
+      }
+      #gt-backdrop {
+        position: absolute;
+        inset: 0;
+        background: #000000;
+      }
+      #gt-canvas {
+        position: absolute;
+        top: 0;
+        left: 0;
+        width: 1920px;
+        height: 1080px;
+      }
+      /* Off-screen decode well: the <img> elements live in the DOM so the page
+         load event waits for them, but they are never composited themselves —
+         WebGL reads them as textures. The well is clipped to 1px; the images
+         inside keep their natural layout size on purpose, because texImage2D
+         uploads an <img> at its LAID-OUT size — sizing them down with CSS
+         uploads a 1x1 texture and every panel samples one dark pixel. */
+      #gt-assets {
+        position: absolute;
+        top: 0;
+        left: 0;
+        width: 1px;
+        height: 1px;
+        overflow: hidden;
+        opacity: 0;
+        pointer-events: none;
+      }
+    </style>
+  </head>
+  <body>
+    <!--
+      Content slots. Every panel in the corridor is a slot, and `images` fills a
+      share of them with your own artwork — drop the files in the project's
+      assets/ and list them, either by editing the `images` default below or from
+      the host composition:
+
+        <div
+          data-composition-id="gallery-tunnel"
+          data-composition-src="compositions/gallery-tunnel.html"
+          data-start="0" data-duration="12" data-track-index="0"
+          data-width="1920" data-height="1080"
+          style="--images: assets/shot-1.png, assets/shot-2.png, assets/shot-3.png; --imagemix: 0.7"
+        ></div>
+
+      Any number of images works; they are dealt to slots by hash, so one image
+      recurs at different depths rather than appearing once. Each is contain-fit
+      inside its slot, so a 16:9 screenshot keeps its aspect. `imageMix` sets the
+      image-vs-colour split (1 = every filled slot is an image), `fill` how many
+      slots are filled at all.
+    -->
+    <div
+      id="gt-root"
+      data-composition-id="gallery-tunnel"
+      data-root="true"
+      data-width="1920"
+      data-height="1080"
+      data-start="0"
+      data-duration="12"
+      data-composition-variables='[
+        {"id":"images","type":"string","label":"Image slots: comma-separated paths, tiled into the panels (e.g. assets/shot-1.png,assets/shot-2.png)","default":"","placeholder":"assets/shot-1.png,assets/shot-2.png"},
+        {"id":"imageMix","type":"number","label":"Image share of filled slots (0 = all colour, 1 = all images)","default":0.5,"min":0,"max":1,"step":0.05},
+        {"id":"speed","type":"number","label":"Flight speed","default":3,"min":0,"max":8,"step":0.1,"unit":"segments/s"},
+        {"id":"palette","type":"string","label":"Slab palette: comma-separated hex colours","default":"#FF6A00,#AB54F7,#EA3737,#0072E3,#00AA3C,#FFB200"},
+        {"id":"grid","type":"number","label":"Grid density: slots per wall face per axis (2 = 4 per face, 16 per segment)","default":2,"min":1,"max":4,"step":1},
+        {"id":"fill","type":"number","label":"Slot fill rate","default":0.5,"min":0,"max":1,"step":0.05},
+        {"id":"fog","type":"number","label":"Fog distance: depth at which the corridor reaches pure backdrop","default":14.25,"min":3,"max":14.5,"step":0.25,"unit":"segments"},
+        {"id":"edgeColor","type":"color","label":"Edge line colour","default":"#B0B0B0"},
+        {"id":"edgeOpacity","type":"number","label":"Edge line opacity","default":0.5,"min":0,"max":1,"step":0.05},
+        {"id":"backdrop","type":"color","label":"Backdrop and fog colour","default":"#000000"}
+      ]'
+    >
+      <div id="gt-backdrop"></div>
+      <canvas id="gt-canvas" width="1920" height="1080"></canvas>
+      <div id="gt-assets" aria-hidden="true" data-layout-allow-overflow></div>
+
+      <!-- Driver clip: gives HyperFrames a timed element to own on track 0. -->
+      <div
+        id="gt-drv"
+        class="clip"
+        data-start="0"
+        data-duration="12"
+        data-track-index="0"
+        style="position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none"
+      ></div>
+    </div>
+
+    <script>
+      (function () {
+        var DUR = 12;
+        var W = 1920;
+        var H = 1080;
+
+        // Fixed tunnel geometry, measured off the reference.
+        var TUNNEL_WIDTH = 2;
+        var TUNNEL_HEIGHT = 1.8;
+        var SEGMENT_DEPTH = 1;
+        var NUM_SEGMENTS = 15;
+        var LINE_RADIUS = 0.003;
+        var FOV = 75;
+        var INSET = 0.94; // slab gutter inside its cell, so tiles read as discrete
+        var SKIN = 0.002; // push slabs just behind the wall plane so edges stay on top
+
+        var ROOT = document.getElementById("gt-root");
+        var CS = getComputedStyle(ROOT);
+
+        // `data-composition-variables` is the single owner of every declared
+        // default — parse it rather than repeating each default a second time
+        // in JS. `window.__hyperframes` is NOT guaranteed to exist yet when this
+        // inline script runs, so it can only ever be an override, never the
+        // source. Precedence: host CSS custom property, runtime variable bag,
+        // declared default.
+        var DECL = {};
+        JSON.parse(ROOT.getAttribute("data-composition-variables") || "[]").forEach(function (v) {
+          DECL[v.id] = v.default;
+        });
+        var HF = window.__hyperframes;
+        var V = (HF && HF.getVariables && HF.getVariables()) || {};
+
+        function raw(id) {
+          var css = CS.getPropertyValue("--" + id.toLowerCase()).trim();
+          if (css !== "") return css;
+          if (V[id] !== undefined && V[id] !== "") return V[id];
+          return DECL[id];
+        }
+        function num(id) {
+          var n = parseFloat(raw(id));
+          return isFinite(n) ? n : 0;
+        }
+        function str(id) {
+          var s = raw(id);
+          return typeof s === "string" ? s.trim() : "";
+        }
+        function list(id) {
+          return str(id)
+            .split(",")
+            .map(function (s) {
+              return s.trim();
+            })
+            .filter(function (s) {
+              return s !== "";
+            });
+        }
+
+        var SPEED = num("speed");
+        var GRID = Math.max(1, Math.min(4, Math.round(num("grid"))));
+        var FILL = num("fill");
+        var IMAGE_MIX = num("imageMix");
+        var FOG_FAR = Math.max(3, Math.min(14.5, num("fog")));
+        var EDGE_OPACITY = num("edgeOpacity");
+        var EDGE_COLOR = str("edgeColor");
+        var BACKDROP = str("backdrop");
+        var PALETTE = list("palette");
+        var IMAGE_SRCS = list("images");
+
+        document.getElementById("gt-backdrop").style.background = BACKDROP;
+
+        // How far behind the camera a segment travels before it recycles. Tying
+        // it to the fog distance is the whole trick: the recycle boundary lands
+        // at exactly FOG_FAR, so a segment reappears already fogged to pure
+        // backdrop and nothing ever pops in at the far end. One owner for the
+        // invariant — move the fog and the boundary follows.
+        var BACK = Math.max(0, Math.min(1.5, NUM_SEGMENTS * SEGMENT_DEPTH - FOG_FAR));
+
+        // Deterministic 2D integer hash — the only source of "randomness".
+        // Content at frame N is a pure function of (absolute segment, slot).
+        function hash2(a, b) {
+          var h = Math.imul(a | 0, 0x27d4eb2d) ^ Math.imul(b | 0, 0x165667b1);
+          h = Math.imul(h ^ (h >>> 15), 0x2545f491);
+          h ^= h >>> 13;
+          return (h >>> 0) / 4294967296;
+        }
+
+        var THREEJS = window.THREE;
+        var canvas = document.getElementById("gt-canvas");
+        var renderer = new THREEJS.WebGLRenderer({
+          canvas: canvas,
+          antialias: true,
+          alpha: false,
+          preserveDrawingBuffer: true,
+        });
+        renderer.setPixelRatio(1);
+        renderer.setSize(W, H, false);
+        renderer.setClearColor(new THREEJS.Color(BACKDROP), 1);
+
+        var scene = new THREEJS.Scene();
+        scene.fog = new THREEJS.Fog(new THREEJS.Color(BACKDROP), 1, FOG_FAR * SEGMENT_DEPTH);
+
+        // Camera sits still at the origin looking down -z; the corridor moves.
+        // Same picture as a moving camera, and the modulo keeps every coordinate
+        // bounded no matter how long the clip runs.
+        var camera = new THREEJS.PerspectiveCamera(FOV, W / H, 0.05, 40);
+        camera.position.set(0, 0, 0);
+        camera.lookAt(0, 0, -1);
+
+        var PLANE = new THREEJS.PlaneGeometry(1, 1);
+
+        var COLOR_MATS = PALETTE.map(function (hex) {
+          return new THREEJS.MeshBasicMaterial({ color: new THREEJS.Color(hex), fog: true });
+        });
+        if (COLOR_MATS.length === 0) {
+          COLOR_MATS.push(new THREEJS.MeshBasicMaterial({ color: 0xffffff, fog: true }));
+        }
+
+        // Caller-supplied content slots. Real <img> elements (so the page load
+        // event waits for the decode) used directly as WebGL textures.
+        var assets = document.getElementById("gt-assets");
+        var IMAGES = IMAGE_SRCS.map(function (src, k) {
+          var el = document.createElement("img");
+          el.id = "gt-img-" + k;
+          el.alt = "";
+          el.src = src;
+          assets.appendChild(el);
+
+          var tex = new THREEJS.Texture(el);
+          tex.minFilter = THREEJS.LinearFilter;
+          tex.magFilter = THREEJS.LinearFilter;
+          tex.generateMipmaps = false;
+          var rec = {
+            aspect: 0,
+            mat: new THREEJS.MeshBasicMaterial({ map: tex, fog: true }),
+          };
+          function ready() {
+            if (!el.naturalWidth) return;
+            rec.aspect = el.naturalWidth / el.naturalHeight;
+            tex.needsUpdate = true;
+          }
+          el.addEventListener("load", ready);
+          ready(); // a cache hit can complete before the listener is attached
+          return rec;
+        });
+
+        var edgeMat = new THREEJS.MeshBasicMaterial({
+          color: new THREEJS.Color(EDGE_COLOR),
+          fog: true,
+          transparent: true,
+          opacity: EDGE_OPACITY,
+        });
+
+        var HW = TUNNEL_WIDTH / 2;
+        var HH = TUNNEL_HEIGHT / 2;
+        var cellZ = SEGMENT_DEPTH / GRID;
+        var cellX = TUNNEL_WIDTH / GRID;
+        var cellY = TUNNEL_HEIGHT / GRID;
+
+        // Four faces of a segment box. `place` maps a cell to a world position
+        // inside the segment (origin at the segment's near boundary, growing
+        // toward -z); `rot` orients the unit plane into that face, inward-facing.
+        // `cw`/`ch` are the cell's extent in the plane's own local axes.
+        var FACES = [
+          {
+            // floor
+            rot: [-Math.PI / 2, 0, 0],
+            cw: cellX,
+            ch: cellZ,
+            place: function (iu, iz) {
+              return [-HW + (iu + 0.5) * cellX, -HH - SKIN, -(iz + 0.5) * cellZ];
+            },
+          },
+          {
+            // ceiling
+            rot: [Math.PI / 2, 0, 0],
+            cw: cellX,
+            ch: cellZ,
+            place: function (iu, iz) {
+              return [-HW + (iu + 0.5) * cellX, HH + SKIN, -(iz + 0.5) * cellZ];
+            },
+          },
+          {
+            // left wall
+            rot: [0, Math.PI / 2, 0],
+            cw: cellZ,
+            ch: cellY,
+            place: function (iu, iz) {
+              return [-HW - SKIN, -HH + (iu + 0.5) * cellY, -(iz + 0.5) * cellZ];
+            },
+          },
+          {
+            // right wall
+            rot: [0, -Math.PI / 2, 0],
+            cw: cellZ,
+            ch: cellY,
+            place: function (iu, iz) {
+              return [HW + SKIN, -HH + (iu + 0.5) * cellY, -(iz + 0.5) * cellZ];
+            },
+          },
+        ];
+
+        var UP = new THREEJS.Vector3(0, 1, 0);
+        // Edges are solid tube geometry, not lines: a cylinder thickens with
+        // perspective the way a real moulding does, which is the whole reason
+        // the corridor reads as built rather than drawn.
+        function tube(group, ax, ay, az, bx, by, bz) {
+          var dx = bx - ax,
+            dy = by - ay,
+            dz = bz - az;
+          var len = Math.sqrt(dx * dx + dy * dy + dz * dz);
+          if (len < 1e-6) return;
+          var mesh = new THREEJS.Mesh(
+            new THREEJS.CylinderGeometry(LINE_RADIUS, LINE_RADIUS, len, 6, 1),
+            edgeMat,
+          );
+          mesh.position.set((ax + bx) / 2, (ay + by) / 2, (az + bz) / 2);
+          mesh.quaternion.setFromUnitVectors(UP, new THREEJS.Vector3(dx / len, dy / len, dz / len));
+          group.add(mesh);
+        }
+
+        function buildEdges(group) {
+          var D = SEGMENT_DEPTH;
+          var k, j, u, z;
+          // The four corner runs (and any interior wall divisions) come from the
+          // side walls; floor/ceiling only contribute their interior lines, so
+          // corners are drawn once and never double-blend at 50% opacity.
+          for (k = 1; k < GRID; k++) {
+            u = -HW + k * cellX;
+            tube(group, u, -HH, 0, u, -HH, -D);
+            tube(group, u, HH, 0, u, HH, -D);
+          }
+          for (k = 0; k <= GRID; k++) {
+            u = -HH + k * cellY;
+            tube(group, -HW, u, 0, -HW, u, -D);
+            tube(group, HW, u, 0, HW, u, -D);
+          }
+          // Ring lines at each depth boundary. The far boundary belongs to the
+          // next segment, so stop one short and the tiling stays seamless.
+          for (j = 0; j < GRID; j++) {
+            z = -j * cellZ;
+            tube(group, -HW, -HH, z, HW, -HH, z);
+            tube(group, -HW, HH, z, HW, HH, z);
+            tube(group, -HW, -HH, z, -HW, HH, z);
+            tube(group, HW, -HH, z, HW, HH, z);
+          }
+        }
+
+        var segs = [];
+        for (var i = 0; i < NUM_SEGMENTS; i++) {
+          var group = new THREEJS.Group();
+          var panels = [];
+          for (var f = 0; f < FACES.length; f++) {
+            var face = FACES[f];
+            for (var iz = 0; iz < GRID; iz++) {
+              for (var iu = 0; iu < GRID; iu++) {
+                var mesh = new THREEJS.Mesh(PLANE, COLOR_MATS[0]);
+                var p = face.place(iu, iz);
+                mesh.position.set(p[0], p[1], p[2]);
+                mesh.rotation.set(face.rot[0], face.rot[1], face.rot[2]);
+                mesh.visible = false;
+                group.add(mesh);
+                panels.push({ mesh: mesh, cw: face.cw * INSET, ch: face.ch * INSET });
+              }
+            }
+          }
+          buildEdges(group);
+          scene.add(group);
+          segs.push({ group: group, panels: panels });
+        }
+
+        // Contain-fit so a supplied screenshot keeps its aspect inside the slot
+        // instead of being squashed to the cell (wall cells are portrait).
+        function fit(p, ar) {
+          if (!ar) {
+            p.mesh.scale.set(p.cw, p.ch, 1);
+            return;
+          }
+          if (ar > p.cw / p.ch) p.mesh.scale.set(p.cw, p.cw / ar, 1);
+          else p.mesh.scale.set(p.ch * ar, p.ch, 1);
+        }
+
+        // Everything about frame t is computed from t alone. `d` is the distance
+        // flown in segments; `a` is the ABSOLUTE segment number occupying pool
+        // slot i right now, which is what content hashes and the every-other
+        // rhythm key off — so a segment carries the same panels every time it is
+        // looked at, no matter how the timeline is scrubbed.
+        function draw(t) {
+          var d = SPEED * t;
+          for (var i = 0; i < NUM_SEGMENTS; i++) {
+            var seg = segs[i];
+            var a = i + NUM_SEGMENTS * Math.ceil((d - i - BACK) / NUM_SEGMENTS);
+            seg.group.position.z = -(a - d) * SEGMENT_DEPTH;
+
+            var lit = a % 2 === 0;
+            var panels = seg.panels;
+            for (var s = 0; s < panels.length; s++) {
+              var p = panels[s];
+              if (!lit || hash2(a, s * 4 + 1) >= FILL) {
+                p.mesh.visible = false;
+                continue;
+              }
+              p.mesh.visible = true;
+              if (IMAGES.length > 0 && hash2(a, s * 4 + 2) < IMAGE_MIX) {
+                var im = IMAGES[Math.floor(hash2(a, s * 4 + 4) * IMAGES.length) % IMAGES.length];
+                p.mesh.material = im.mat;
+                fit(p, im.aspect);
+              } else {
+                var ci = Math.floor(hash2(a, s * 4 + 3) * COLOR_MATS.length) % COLOR_MATS.length;
+                p.mesh.material = COLOR_MATS[ci];
+                p.mesh.scale.set(p.cw, p.ch, 1);
+              }
+            }
+          }
+          renderer.render(scene, camera);
+        }
+
+        window.__timelines = window.__timelines || {};
+        var tl = gsap.timeline({ paused: true });
+
+        // Repaint from a property SETTER, not from onUpdate: gsap's seek(t)
+        // suppresses events by default, so an onUpdate callback silently never
+        // fires on a scrub and the canvas freezes on frame 0. Tweened values are
+        // always written during render, suppressed or not.
+        var driver = { _t: 0 };
+        Object.defineProperty(driver, "t", {
+          get: function () {
+            return this._t;
+          },
+          set: function (v) {
+            this._t = v;
+            draw(v);
+          },
+        });
+        tl.to(driver, { t: DUR, duration: DUR, ease: "none" }, 0);
+        window.__timelines["gallery-tunnel"] = tl;
+
+        draw(0);
+      })();
+    </script>
+  </body>
+</html>
diff --git a/registry/blocks/gallery-tunnel/registry-item.json b/registry/blocks/gallery-tunnel/registry-item.json
new file mode 100644
index 0000000000..339c307eb9
--- /dev/null
+++ b/registry/blocks/gallery-tunnel/registry-item.json
@@ -0,0 +1,101 @@
+{
+  "$schema": "https://hyperframes.heygen.com/schema/registry-item.json",
+  "name": "gallery-tunnel",
+  "type": "hyperframes:block",
+  "title": "Gallery Tunnel",
+  "description": "An infinite corridor of panels: a square tunnel receding to a vanishing point, its floor, ceiling and walls tiled with saturated colour slabs and caller-supplied images that swell toward camera and exit past you, the far end dissolving into fog.",
+  "stability": "experimental",
+  "dimensions": {
+    "width": 1920,
+    "height": 1080
+  },
+  "duration": 12,
+  "tags": ["webgl", "3d", "background", "showcase", "depth", "loop"],
+  "files": [
+    {
+      "path": "gallery-tunnel.html",
+      "target": "compositions/gallery-tunnel.html",
+      "type": "hyperframes:composition"
+    }
+  ],
+  "params": [
+    {
+      "key": "--images",
+      "label": "Image slots: comma-separated paths, tiled into the panels (e.g. assets/shot-1.png,assets/shot-2.png)",
+      "type": "text",
+      "default": ""
+    },
+    {
+      "key": "--imagemix",
+      "label": "Image share of filled slots (0 = all colour, 1 = all images)",
+      "type": "number",
+      "default": "0.5",
+      "min": 0,
+      "max": 1,
+      "step": 0.05
+    },
+    {
+      "key": "--speed",
+      "label": "Flight speed (segments per second)",
+      "type": "number",
+      "default": "3",
+      "min": 0,
+      "max": 8,
+      "step": 0.1
+    },
+    {
+      "key": "--palette",
+      "label": "Slab palette: comma-separated hex colours",
+      "type": "text",
+      "default": "#FF6A00,#AB54F7,#EA3737,#0072E3,#00AA3C,#FFB200"
+    },
+    {
+      "key": "--grid",
+      "label": "Grid density: slots per wall face per axis (2 = 4 per face, 16 per segment)",
+      "type": "number",
+      "default": "2",
+      "min": 1,
+      "max": 4,
+      "step": 1
+    },
+    {
+      "key": "--fill",
+      "label": "Slot fill rate",
+      "type": "number",
+      "default": "0.5",
+      "min": 0,
+      "max": 1,
+      "step": 0.05
+    },
+    {
+      "key": "--fog",
+      "label": "Fog distance in segments: depth at which the corridor reaches pure backdrop",
+      "type": "number",
+      "default": "14.25",
+      "min": 3,
+      "max": 14.5,
+      "step": 0.25
+    },
+    {
+      "key": "--edgecolor",
+      "label": "Edge line colour",
+      "type": "color",
+      "default": "#B0B0B0"
+    },
+    {
+      "key": "--edgeopacity",
+      "label": "Edge line opacity",
+      "type": "number",
+      "default": "0.5",
+      "min": 0,
+      "max": 1,
+      "step": 0.05
+    },
+    {
+      "key": "--backdrop",
+      "label": "Backdrop and fog colour",
+      "type": "color",
+      "default": "#000000"
+    }
+  ]
+}
diff --git a/registry/registry.json b/registry/registry.json
index bff47f2948..342a7448f1 100644
--- a/registry/registry.json
+++ b/registry/registry.json
@@ -39,6 +39,10 @@
       "name": "data-chart",
       "type": "hyperframes:block"
     },
+    {
+      "name": "gallery-tunnel",
+      "type": "hyperframes:block"
+    },
     {
       "name": "us-map",
       "type": "hyperframes:block"