KeyframingExample

VisIt provides a keyframing mode that makes it possible for the user to define how plot attributes and the view change dynamically over time. Since keyframing can be difficult to set up, this page provides a simple example that lets you set up a plot whose opacity changes over time. Once a keyframe animation has been set up, you can use the "Simple movie" option in VisIt's Save movie wizard to create a movie file containing the animation.

Steps:

visit -o /path/to/visit/data/globe.silo Open Keyframe window Turn on the Keyframing enabled check box, type 15 for number of frames and press Enter to make sure that the number gets entered. Click Apply button Add Pseudocolor plot of speed Click Draw button in Main window Click the Apply button. This causes the new plot to be put into keyframe mode (green range all the way across the window).

Making plot keyframes

Now that the visualization window is in Keyframe mode, you can make plot keyframes.

Change Pseudocolor plot opacity to 50% and click the Apply button in its plot attributes window Change the time step to frame 7 using the time slider in the Main window or in the Keyframe window Change the Pseudocolor opacity to 0% and click the Apply button to create a keyframe. Keyframes show up in the Keyframe window as small black diamonds along the keyframe time axis. Set the time step to frame 14 using the time slider Change the Pseudocolor opacity to 100% and click the Apply button to create a keyframe. Click Play to see the opacity of the Pseudocolor plot change over time.

Making view keyframes

In addition to keyframing plot attributes, VisIt allows you to create keyframed views. Keyframed views can be useful for zooming into areas of interest or flying into a visualization while it plays. Simple types of view rotations are better handled in the Save movie wizard by making a custom movie template.

The controls for making view keyframes are located in the View window, which is accessible from the Controls menu in the Main window. There are two controls that are of interest when creating view keyframes. The first one is the Make camera keyframe from view button located in the 'Advanced' tab. When that button is clicked, VisIt adds the current view as a view keyframe for the current animation frame. If you want the view to change when you animate through time, you must also turn on the Copy view from camera check box and click the Apply button. The Copy view from camera check box causes VisIt to copy the interpolated keyframe view into the camera used to render the visualization.

In order to add view keyframes in the context of the above example, do the following:

Change the time slider to frame 0 Click the Make camera keyframe from view button in the View window to add a view keyframe Change the time slider to frame 7 Rotate the view a little in the visualization window, maybe zoom some too. Click the Make camera keyframe from view button in the View window to add a view keyframe Change the time slider to frame 14 Rotate the view more Click the Make camera keyframe from view button in the View window to add a view keyframe Click play to see the view change using your view keyframes