Animating Objects in a Scene

Simcenter STAR-CCM+ provides multiple approaches for exploring solutions using moving images. In-scene animation provides dynamic observation of specific scene displayers. Exporting to an MP4 file builds an animation while a solution progresses (particularly transient solutions). Screenplay animation gives a higher level of story construction and control.

In-scene animations are defined at the displayer level and are generally used for repeating sequences that you can view interactively and export to file. Screenplay allows you to create story-based sequences that can include these in-scene animations, but also extends to multiple scenes, changing camera angles, and frame-based control over relevant properties of post-processing objects. For guidance on using Screenplay, see Screenplay Animation.

Activating in-scene animation successfully requires you to choose the right combination of displayer and input parts. Generally, you must include one or more derived parts in the Parts property for the displayer. For example, if you have a scalar displayer whose input part is a symmetry boundary, no animation is seen. Instead, you must include a plane section derived part that Simcenter STAR-CCM+ can sweep through the solution domain.

To activate in-scene animation for a displayer:

Ensure that at least one of the input parts for the displayer is a derived part. Use the following table as a guide:


Displayer Type	Supported Derived Parts for Animation	Animation Effects
Scalar, Geometry	Plane section or isosurface A single section plane permits continuous sweeps only; a multiple section plane also supports discrete sweep animation.	Sweep from a start point to an end point in either a continuous movement or by shifting between discrete locations.
Vector	Any parts on which vectors are displayed	Vectors moving in direction of flow from inlet to outlet; sweep
Streamline	Streamline	Tracers

Select the [displayer] > Animations node and set Animation Mode to one of the following options:
- For a scalar or geometry displayer: Continuous Sweep or Discrete Sweep
- For a vector displayer: Pulse, Continuous Sweep, or Discrete Sweep
- For a streamline displayer: Tracers
Select the corresponding child node and set its properties.

Continuous or Discrete Sweeps

Use the properties to control the speed at which the surface sweeps through the domain. For the discrete option, the stops through the sweep are defined by the multiple sections on the underlying derived part.

Pulse

Control the total time required for a glyph to travel from the inlet to the outlet using Cycle Time (sec).

Tracers

Control the Delay between tracers, the Head Size, Tail length, and the overall time required for a tracer to travel from the inlet to the outlet (Cycle time).
To play and control the animation in the scene, use the controls in the Animation toolbar:
- (Play/pause animation in active scene)
- (Stop animation in active scene)
- (Play/Pause Animation)
- When the animation is in freeze-frame, you can move the animation ahead or back one frame at a time. Click the (Single Step Forward) to move ahead and the (Single Step Backward) button to move back.
To increase or decrease the number of frames per second in the animation, select the [scene] > Attributes > Scene animation node and set Target Frame Rate (fps) to a new value.
To export the animation as a movie file or as a series of images, do the following:
1. In the Animation toolbar, click (Write Movie).
2. In the Write animation dialog, prepare the specifications for the recording:
  
  For a detailed list of properties, see Write Animation Dialog.
3. Enter the target File name and click Save.
If you exported a directory of .png files, you can create an animation using a media program of your choice. Movie files (.mp4) can be played in a variety of video playback software tools on Windows and Linux.
For sweep animations, if the animation plays slowly in the scene, you can activate the Precompute Steps property.

By default, Simcenter STAR-CCM+ must access the server during each animation step to calculate values and geometry for the derived part. When you activate precomputation, Simcenter STAR-CCM+ prepares these calculations before you start the animation, allowing you to animate the derived part without constant server access. Precomputed steps improve the performance of the animation with a higher average frame rate, but the precomputation requires more time, and the animation requires more memory. The requirements for time and memory increase proportionally to the specified number of steps.