| { |
| "id": "single-software-execution--cli--blender--task-03--ubuntu", |
| "snapshot": "Blender-4.2.3", |
| "instruction": "Menger Sponge via Geometry Nodes (Repeat Zone) `/home/user/Desktop/scene.blend` contains a single mesh object `Sponge` at the world origin. Launch Blender by running `blender` from a terminal. On this machine, use `/opt/blender/blender` for Blender command-line or background runs when working on `scene.blend`.\n\nIts mesh data is empty (0 verts / 0 edges / 0 faces) and the modifier stack is empty. Your job is to add a **Geometry Nodes** modifier to `Sponge` that procedurally builds a **depth-3 Menger sponge** using a **Repeat Zone** (`GeometryNodeRepeatInput` + `GeometryNodeRepeatOutput`). Save your result as `/home/user/Desktop/answer.blend`. The GN modifier must remain on `Sponge` -- do **not** apply it. The base mesh stays empty; only the evaluated mesh (via depsgraph) contains the sponge. ## Construction spec The Menger sponge construction starts from a unit cube occupying the axis-aligned box `[0, 1]^3`. Each iteration subdivides every current cube into a `3 x 3 x 3` grid of 27 sub-cubes and removes the 7 that sit at (a) the volume-center position and (b) the 6 face-center positions of the parent cube, keeping the 20 that sit on parent edges/corners. Child cubes have side length `parent_size / 3`. Counts per iteration (number of remaining cubes): - Iter 0: 1 - Iter 1: 20 - Iter 2: 400 - Iter 3: 8000 At depth 3 each cube has side length `1/27` and the 8000 cubes together fill `[0, 1]^3`. ## Required architecture - The GN tree must expose an integer Group Input socket named `Iterations` with default value `3`. Its value is consumed by the Repeat Zone. - The zone body must execute N times (where N = `Iterations`). On each iteration, each current cube becomes 20 sub-cubes (a 3x3x3 grid minus the 7 center/face-centers), scaled to 1/3 of the current size. - A clean and correct pattern: 1. Before the Repeat Zone, seed the geometry with a single point at `(0.5, 0.5, 0.5)` carrying a float attribute `size = 1.0`. 2. Inside the zone: build a 20-point \"sub-grid\" (the valid Menger offsets at `(i-1, j-1, k-1) / 3` for i,j,k in {0,1,2} excluding the 7 bad offsets), instance it on the current point cloud via `Instance on Points` with `Scale` set to the `size` attribute, `Realize Instances`, and write `size = old size / 3` back to the attribute. 3. After the zone, instance a unit `Mesh Cube` on each final point with `Scale` = `size`, and `Realize Instances`. - Connect the final realized geometry to the Group Output. You may build the 20-point sub-grid any way you like (pure-GN with `Mesh Line` + `Instance on Points` + `Delete Geometry`, or as an auxiliary mesh data-block referenced via `Object Info`, or explicit `from_pydata`). The sub-grid only needs to have 20 vertices at the correct Menger offsets. ## Requirements 1. `/home/user/Desktop/answer.blend` exists and opens. 2. Scene contains mesh object `Sponge` at the world origin with exactly one modifier, of type `NODES`, referencing a non-empty node group. 3. The node group contains a `GeometryNodeRepeatInput` (Repeat Zone); its effective iteration count is `3`. - Either the RepeatInput's `Iterations` input socket is driven by a Group Input socket whose default (or modifier override) is `3`, or the RepeatInput's `Iterations` default is `3`. 4. `Sponge.data` (the base mesh) is empty -- the modifier is **not** applied. 5. The evaluated mesh (via depsgraph) has: - vertex count in `[10000, 200000]` - face count in `[5000, 150000]` - bounding box (in world space) equal to `[0, 1]^3` within tolerance `1e-3` 6. At least 95% of evaluated edges are 2-faced (\"manifold-ish\" interior).", |
| "source": "https://docs.blender.org/manual/en/4.1/; https://docs.blender.org/api/4.1/; https://developer.blender.org/docs/release_notes/4.1/; https://www.loc.gov/preservation/digital/formats/fdd/fdd000507.shtml", |
| "config": [ |
| { |
| "type": "upload_file", |
| "parameters": { |
| "files": [ |
| { |
| "local_path": "task-03/init_file/scene.blend", |
| "path": "/home/user/Desktop/scene.blend" |
| } |
| ] |
| } |
| } |
| ], |
| "trajectory": "trajectories/", |
| "related_apps": [ |
| "blender" |
| ], |
| "artifact_paths": [ |
| "/home/user/Desktop/answer.blend" |
| ], |
| "evaluator": { |
| "postconfig": [ |
| { |
| "type": "upload_file", |
| "parameters": { |
| "files": [ |
| { |
| "local_path": "task-03/eval.py", |
| "path": "/home/user/Desktop/eval.py" |
| } |
| ] |
| } |
| } |
| ], |
| "func": "exact_match", |
| "result": { |
| "type": "vm_command_line", |
| "command": "python3 /home/user/Desktop/eval.py", |
| "shell": "true" |
| }, |
| "expected": { |
| "type": "rule", |
| "rules": { |
| "expected": "True\n" |
| } |
| } |
| }, |
| "proxy": false, |
| "fixed_ip": false, |
| "possibility_of_env_change": "low" |
| } |
|
|
