Simulation Time Control Property Editor
 
 
 

Simulation | Caching Files

Sets the timing and allows you to cache the rigid body simulation or ICE simulation in the current simulation environment.

To display, do one of the following:

Simulation

The parameters on this tab let you set up the playback options for the current simulation environment.

For more information, see Playing an ICE Simulation.

Active

Toggles the activeness of the simulation.

Time Reference

Offset

Number of frames by which to offset the simulation.

Duration

Number of frames over which the simulation occurs.

Current Simulation Frame

For information purposes only. Displays the current scene's timeline frame for the simulation.

Copy from Scene

Copies the frame range of the scene's timeline to the Offset and Duration values, if you don't have the Use start/end frame options selected. This is a quick way to set the simulation's frame range.

Remember that if you change the timeline's start or end frames, you will need to update the simulation's frame range as well.

Copy to Scene

Copies the simulation's Offset and Duration values to the scene's timeline.

Scene Time

Use start frame

Uses the scene's start frame and keeps a link to it. When you update the start frame in the scene's timeline, the simulation is also automatically updated to use the new frame.

The Use start/end frame options set the Offset and Duration values to match the scene's time, so when you make a change to the scene timeline's start or end frame, the change is automatically reflected in the Offset and Duration values.

When the Use start/end frame options are active, you cannot directly change the Offset or Duration values.

Use end frame

Uses the scene's last frame and keeps a link to it. When you update the end frame in the scene's timeline, the simulation is also automatically updated to use the new frame.

Toggle Simulation Info

Turns on/off the simulation information that is displayed in the corner of the active viewport. The information shown is for the current simulation environment and includes the start and end of the simulation, the last frame that has been cached, whether the cache is on, and whether the cache is locked.

You can also set the Show Simulation Info option on the Stats page in the Camera Visibility Options property editor (press Shift+S) for a viewport.

Play Mode

Select from these options for how the simulation is played back.

When doing a final render of the scene and you are doing distributed rendering or using motion blur, you should turn on caching and use the Standard mode; otherwise, you can use Live mode for rendering as well. You cannot, however, see the effects of motion blur when using Interactive mode.

 

Standard: plays the simulation from the first frame. It calculates the simulation only when you go forward to a different frame. If you change one of the elements in the simulation, the simulation is recomputed from the initial state at the next frame change. If you go to a previous frame (playing backwards), the simulation is not recomputed.

Standard mode calculates the simulation only when you go to a different frame, either by clicking the Play button below the timeline or moving the playback cursor.

 

Live: updates the simulation at each frame with any change that you make. This mode allows you to play a simulation continuously for quick editing and tweaking. You can then view the effect of any modifications in real time.

Live mode is best when you play the simulation with looping on — this way you can tune parameters and immediately see what happens without restarting the simulation from its first frame. Any change you make to any elements within the simulation environment affects the simulation only from that point on: the simulation is not recalculated from the start.

As soon as you skip forward, the simulation is computed for the current frame from all of the intermediate frames.

When you drag the playback cursor forward in the timeline or click the Play button, the simulation is updated to the current frame.

 

Interactive: updates the simulation as you interact directly with the simulated object, such as by dragging it to a different location. This is similar to how quick stretch works when you select a quick-stretched object and move it around.

Interactive mode is useful for quickly trying out different variations of the simulation without having to play it back. For example, while the simulation is playing, you can go to a specific frame and then move a rigid body to a new position or rotate it to quickly test out the resulting simulation.

For spring-based control objects in rigs (see Spring Operators for Tail, Ear, and Belly Rig Controls), you need to select this mode to simulate their movement (this is their default setting).

Caching Files

The parameters on this tab let you create point cache files, simulation environment caches, and cache file sources and clips for ICE simulations.

For non-ICE rigid body simulations, you can create simulation environment caches and action sources and clips.

For general information, see Creating ICE Simulation Environment Cache Files.

NoteTo change the default path, file name syntax, and file format used for the cache files, see the File Cache Path Template options in the Simulation Preferences.

Cache on Playback

Caches (stores) the frames of the simulation to the file as defined below when you play back the simulation.

You can also cache the frames by jumping to the last frame of the simulation that you want to cache: all the frames of the simulation up to that frame are cached.

You can select any of the Play Mode options (on the Simulation tab) for caching. However, if you're doing distributed rendering or using motion blur, it's recommended that you use the Standard mode.

Lock Playback Cache

Locks the frames that have already been cached in the cache source so that they are not resimulated.

This is particularly useful when you're happy with the current state of the simulation and want to make sure that it won't change. Locking a cache can be of great help before sending it to a render farm.

Path

Enter the path of the cache file for this instance of caching. Click the browse (...) button to select a different path.

This path is automatically set according to the Default Path option that is set in the Simulation Preferences.

Tokens

Opens the help topic for Tokens and Templates so that you can see which tokens are available to add to the Path or File Name syntax. You can add any of the Universal tokens, in addition to the Caching ones.

The tokens used in the Path and File Name are automatically set according to what's used in the Simulation Preferences.

File Name

Name of the cache file to be saved. This is the syntax: [object]_[version]_[frame]

To add frame padding to the frame numbers, see the description for the [Frame] token in Tokens and Templates for more information.

Version

Enter any string to identify this version of the same cache file, such as Take1 or A, B, C, and so on.

Format

The format of the cache file. You can choose from:

  • ICECache (.icecache)

  • Custom. Enter its file extension in the text box beside this one.

See Cache File Formats for more information.

The default format is set by the Cache Type in the Simulation Preferences.

Resolved Path

Displays the path and file name to use for the cache file.

Save Cache to Mixer

Click this button to create a source and optional clip from the environment cache file.

The Store Environment Cache in Mixer dialog box opens when you click this button.

  • For ICE simulations, click OK and the cache file source is created in the model's Mixer folder.

  • For rigid body simulations, select the RBD Action Name. This is the action source that is created from the rigid bodies' environment cache file. This source is kept in the model's Mixer node, so if you export your model, the cached simulation is included with it. You can cache one action source per model.

Add Clip to Mixer: Optionally, you can instantiate this source as a clip in the animation mixer if you select this option.

When you create a clip from the source file, any simulation on the objects will be removed. If you want to keep the simulation, you may want to back up your scene before selecting applying the clip to the animation mixer.

  • For ICE simulations, a cache clip is created from the cache file source and applied in the animation mixer. You will get a message about whether to remove or keep the simulation — see Creating Cache File Sources and Clips for more information.

  • For non-ICE rigid body simulations, an action clip is created from the action source and applied in the animation mixer. The simulation is removed from the rigid bodies — see Creating Action Sources and Clips from the Cache for more information.

Scene Simulation Cache on File Nodes

Note: These options appear only if you open the Simulation Time Control property editor via the The Cache Manager.

If there is a cache file being read from a Cache on File node in any scene object's ICE tree, information about the object and its cache file appears in a table here.

Select an object in the table, then click the Inspect Obj button to open the object's Cache on File property editor.