--- task_categories: - other --- # 4DCodeBench-Synthetic [Project page](https://4dcodebench.com) | [Paper](https://huggingface.co/papers/2610.03715) | [Code](https://github.com/4DCodeBench/4DCodeBench) The 100 synthetic cases of 4DCodeBench: a rendered video of a simulated scene and the ground-truth world behind it. The worlds come from ten simulators, and each carries the geometry of every frame and the trajectory of the moving matter, which is what a reconstruction is scored against. ## Layout ```text videos/.mp4 the reference video, as the benchmark reads it worlds/.h5 the ground-truth world, packed ``` 43 GB of worlds and 188 MB of video. `videos/.mp4` is the same video that sits inside `worlds/.h5`, byte for byte, so either copy can be used. ## What a world holds ```text camera.json {"intrinsics": K, "extrinsic": E}, the fixed camera the video was rendered through render.mp4 the reference video meshes/ each rendered object's vertices and triangles at every frame dynamics/ the moving matter: pos (frames, points, 3), column j the same material through time solver/ a liquid solver's own bake, on the eight liquid cases ``` Positions are in world-space metres with Z up. A mesh may change its vertex count and topology from frame to frame, as a liquid surface or a fracture does; `dynamics/` is where the frame-to-frame correspondence lives. The eight liquid cases (B_02, B_09, B_11, B_13, B_14, B_19, B_27, B_28) also carry `solver/manifest.json`, `solver/CACHE.json` and `solver/cache/`, the bake their surface was meshed from. Unpack a world into a directory with `pack_world.py unpack worlds/.h5 -o ` from the benchmark's code release. The packing is lossless and bit-exact in both directions. ## Cases | case | scene | case | scene | |---|---|---|---| | B_01 | `arch_tower_projectile_collapse` | G_12 | `paper_sheet_folded_in_half` | | B_02 | `bottle_pour_into_glass` | G_13 | `paste_drains_through_funnels` | | B_03 | `bowling_strike_pin_scatter` | G_14 | `ribbon_thin_die_mockup` | | B_04 | `brick_lattice_plinth_ball_impact` | G_15 | `shaving_cream_coils_into_a_pile` | | B_05 | `cloth_curtain_draw_gather` | G_16 | `two_arms_press_plate_on_dough_retract` | | B_06 | `cloth_tape_fanfold_stack` | HM_01 | `HOT_armacat` | | B_07 | `cloth_throw_drape_over_table` | HM_02 | `HOT_boards_flow` | | B_08 | `conveyor_drops_screws_and_nuts_into_bin` | HM_03 | `HOT_faceless` | | B_09 | `dam_break_column_collapse_reference` | HM_04 | `HOT_turkey` | | B_10 | `dial_sweeps_spheres_through_slot` | HM_05 | `HOT_wheel_stress` | | B_11 | `droplet_crown_splash_worthington_jet` | HM_06 | `preview_chains` | | B_12 | `firm_tennis_ball_struck_by_racket` | HM_07 | `preview_fracture` | | B_13 | `fluid_swirl_inside_glass_sphere` | LI_01 | `cipc-arma-rods` | | B_14 | `fountain_tiered_bowl_overflow` | LI_02 | `eevee_curtain_hires` | | B_15 | `glass_chute_ball_topples_cube_tower` | LI_03 | `eevee_domino_abd` | | B_16 | `jelly_beans_drop_scatter` | LI_05 | `libuipc-helicopter-front` | | B_17 | `kapla_keep_diagonal_slow_impact` | LI_07 | `uipc_arma_roller` | | B_19 | `liquid_jet_pool_fill_splash` | LI_08 | `uipc_chain10` | | B_20 | `magnetic_ball_pickup` | LI_09 | `uipc_rods_long10turn` | | B_21 | `many_balls_drum_tumble` | ML_01 | `jets` | | B_23 | `newtons_cradle_elastic_momentum_transfer` | ML_02 | `nacc` | | B_24 | `pool_table_rigid_body_break` | ML_03 | `noodles` | | B_25 | `rope_pendulum_peg_wrap_windup` | ML_04 | `snow` | | B_26 | `seesaw_ball_launcher` | PF_01 | `eevee_puff_real` | | B_27 | `sink_faucet_fill_drain` | PF_02 | `eevee_stack_exact` | | B_28 | `slit_spillway_plunge_basin` | PF_03 | `noodles_ppf` | | B_29 | `soft_bodies_vertical_chute_obstruction` | PF_04 | `ppf_cards` | | B_30 | `soft_tire_bounces_down_stairs` | PF_05 | `ppf_codim` | | B_31 | `tipping_jug_pours_marbles_into_bucket` | PF_06 | `ppf_fishingknot` | | B_32 | `wall_plate_cascade_ball_to_bin` | PF_07 | `ppf_frictionGradient` | | B_33 | `wrecking_ball_chain_impact_demolition` | PF_08 | `ppf_needle` | | CK_01 | `bullet` | PF_09 | `ppf_roller` | | CK_02 | `castle_crasher_lowres` | S_01 | `sph_cereal_bowl36` | | CK_03 | `chimney_ball` | S_02 | `sph_dam_break_floaters` | | CK_04 | `oreo` | S_03 | `sph_water_bell` | | CK_05 | `pumpkin` | TM_01 | `banana_cycles` | | CK_06 | `sand_armadillo` | TM_02 | `goo_cycles` | | CK_07 | `sand_vs_elastic_armadillo` | TM_03 | `sand_stir_cycles` | | CK_08 | `twisting_bar` | Z_01 | `AnisoMPM_meatTear` | | CK_09 | `two_dragons` | Z_02 | `AnisoMPM_tubeCompress` | | G_01 | `anchor_dock_v5` | Z_03 | `armadillo_quartering` | | G_02 | `chain-net-16x16-ball` | Z_04 | `bread_tear` | | G_03 | `clay_spring` | Z_05 | `collapse_sand` | | G_04 | `coup_sand_wheel` | Z_06 | `dam_jello_ball_150` | | G_05 | `coup_sph_mpm` | Z_07 | `dino_bullet` | | G_06 | `coup_sph_rigid` | Z_08 | `dongpoPork` | | G_08 | `frosting_piped_onto_a_cupcake` | Z_09 | `fourbar_materials` | | G_09 | `hydraulic_press_crushes_soft_head` | Z_10 | `lion_viscoelastic` | | G_10 | `ipc_cloth_stack` | Z_11 | `silicone_viscoelastic` | | G_11 | `octopus-knives` | Z_12 | `watermelon_smash` |