Houdini 20.5 Animation

Flipbook animation previews and blocking

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How to create a flipbook animation

A flipbook lets you quickly review the motion and timing in an animation. It captures an image of a viewport for each frame and then plays the images as an animation. This is must faster than actually rendering the animation. You can also attach a sound file to test out how your shot is working with audio.

To...Do this

“Render” a flipbook

Click the Flipbook icon at the bottom of the toolbox (on the left side of the viewer).

Change the flipbook settings

Right-click the Flipbook icon at the bottom of the toolbox (on the left side of the viewer) and choose Flipbook with new settings.

Click Accept. Houdini writes out the frames to your computer’s temporary storage directory. The flipbook opens in MPlay . Use MPlay’s controls to view the flipbook.

Flipbook blocking

You can block out a shot with a flipbook and edit the blocking by dragging keyframes in MPlay.

  1. Set keyframes on all parameters on a character/object.

  2. Right-click the Flipbook icon at the bottom of the toolbox (on the left side of the viewer) and choose Flipbook with new settings.

  3. Turn on Scoped channel and key frames only and Enable block editing.

  4. The keyframe images are highlighted on the MPlay timeline. You can select them with ⇧ Shift + and drag them along the timeline with .

    This lets you change the timings of the blocked out images and preview the changes without creating a new flipbook.

  5. When you are finished, choose Anim ▸ Export Blocking in MPlay to apply the edited timings to your scene.

Scripting flipbook generation

desktop = hou.ui.curDesktop()
scene = desktop.paneTabOfType(hou.paneTabType.SceneViewer)

# Copy the viewer's current flipbook settings
flipbook_options = scene.flipbookSettings().stash()

# Change the settings however you need
# (for example, set the frame range and output filename)
flipbook_options.frameRange( (frame, frame) )
flipbook_options.output(filename)

# Generate the flipbook using the modified settings
scene.flipbook(scene.curViewport(), flip_options)

See hou.FlipbookSettings for information on the settings you can use.

Animation

Getting started

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