Step 1: Enable clip animation
- First, enable the option Animate > Clip animation in the Camera Animation window.
- Then, open the Cross-Section window from the sidebar.
Step 2: Set the first cross-section plane
- Press Activate, and define the cross-section plane (e.g., Set plane > Horizontal, click on a point in the viewport)
- Then press Clip and, if necessary, Flip.
- Press Insert keyframe (Shortcut: I) in the Camera Animation window.
Step 3: Define the next cross-section plane(s)
- Drag the timeline indicator to the right and, if desired, also change the viewpoint.
- Re-define the cross-section plane (e.g., Set Plane > Parallel, set new plane with a left click)
- Insert the second keyframe and repeat this task as many times as desired.
Step 4: Preview & render video
- Bring the timeline indicator to the start and press Play (shortcut: Space) to preview.
- If necessary, jump to a keyframe (double-click the keyframe's triangle), re-define the plane, and press Animate > Update keyframe > Update clip plane.
- In the Cross Section window, define the Plane and Section preview visibility.
- When finished, drag the timeline indicator back to the start, press Export, configure Render video settings, and press Render.
To start the clipping sometime in the middle of the video, insert keyframes for the camera viewpoint before proceeding to Step 2.
You can animate up to three cross-section planes at the same time. Simply activate and define Plane 2 and, if necessary, Plane 3 along with the Main Plane when using the main workflow described above.