CARNAGE GRAINS / DOCUMENTATION

Cache

Save a permanent NPZ point-cache sequence, load it for playback, and manage temporary simulation history.

Point cache settings

Cache FileDefault: //carnage_cache/grain_cache.npz

Folder and base filename for the NPZ point-cache sequence. Frame numbers are added automatically. Use // for a path relative to the saved blend file.

StartDefault: 1

First frame to write with Write Cache.

EndDefault: 250

Last frame to write with Write Cache.

Cache to DiskDefault: Off

Write simulated frames to the point cache during playback. Resetting and simulating again can overwrite existing frame files.

Record Render Motion

Record Render MotionDefault: Off

Record extra motion data for accurate motion blur on Carnage meshes. Enable before starting the simulation. Uses additional memory and cache space, and simulates one extra frame to complete the final exposure.

  1. Set the render frame rate and motion-blur shutter. Use a centered shutter with a duration greater than 0 and no longer than one frame.
  2. Enable Record Render Motion, then Reset and start a fresh simulation.
  3. Write the point cache and let the final exposure finish. The status line shows how many recorded frames are complete.
  4. In Carnage Meshing, choose Motion Blur → Recorded Motion before baking the surface.

A recorded preview needs the following simulated frame to complete its exposure. If you change the frame rate, shutter or recording switch after starting, Reset and simulate again. Keep the render-motion files with the point cache.

Write Cache

  1. Save the .blend before using a relative // path. Set Cache File to the desired folder and base NPZ filename.
  2. Set Start and End, then click Write Cache. It initializes a simulation if needed, reuses available history, and simulates missing frames.
  3. A later Start does not skip simulation pre-roll: the run advances from frame 1, writing only the selected output range.
  4. Press Esc to cancel. Frames already written remain on disk; a cancelled sequence may be incomplete.

Cache to Disk and a new bake can overwrite files at the chosen point-cache path. Use a different folder or base filename to keep another version. After changing animation or simulation setup, Reset and bake again.

Load Point Cache

Set Cache File to the saved sequence and click Load Point Cache. Loading restores the saved simulation settings. The panel shows what is being read and the available on-disk range. Cached playback reads saved data; changing physics values does not recalculate those frames.

Keep the complete cache folder together, including frame files, metadata, attribute/constraint sidecars, and any render-motion data or saved surface reference. A cache that is already loaded for playback cannot be re-baked with Write Cache; Reset and simulate for a new bake.

Temporary history

History RAM (MiB)Default: 1024

RAM budget for simulation history, applied on the next Start or fresh bake. Older frames move to temporary disk storage for scrubbing and resume. One large frame may exceed this budget; solver and Blender memory are additional

Simulation history stores the state needed for scrubbing and continuation. Older frames spill to temporary disk storage when the RAM budget is reached. The budget covers resident history arrays, not all Blender memory or GPU memory; a single large frame may exceed it.

The live readout shows resident history memory and frames. Temporary history is available even with Cache to Disk off, but it is not a permanent bake or crash-recovery format. Reset, a new simulation, loading another .blend, or disabling the addon clears the session history.

Temporary Cache FolderDefault: Empty

Location for temporary simulation history on this computer. Choose an absolute path to use the same folder across projects. Blank uses Blender temporary storage. Applies to new simulations; Reset removes temporary history, not permanent exported caches

Temporary Cache Folder lives in the addon’s Preferences, not in the Cache panel. Blank uses Blender temporary storage; changes apply to new simulations. Keep enough free disk space for spilled history.

Next steps

Load the point cache to use Post Processing and Upres. Use Meshing for surfaces, Geometry Nodes output, and Alembic exports. Point cache and mesh/Alembic cache are separate outputs.

Reference updated 7 November 2026. Defaults describe a fresh setup; saved scenes may use different values.