Form
The Preview Pane is a live preview window showing a looped render of what is represented in the Effects Chain. When changes are made to the settings or Blocks, the preview will update to represent those changes.
When you select an effect preset from the Presets pane, the name of that preset will appear at the bottom of the Effects Chain. If you alter any of the blocks in the effects chain the name will change to "Untitled" until it is saved as a custom preset.
GPU Acceleration
Previewing complex particle simulations can be taxing on computer hardware. Using your GPU to accelerate previews can often speed things up quite a bit.
To enable GPU acceleration in the Designer, click the sprocket icon at the bottom of the Designer.
This opens the Preferences for the Designer. Here you can choose how to accelerate your speed, using either CPU (the computer) or the GPU (the graphics card). Occasionally, acceleration with the GPU might yield unexpected results. But in many cases, accelerating previews with the GPU is much faster.
When choosing GPU, there are two options, Direct and Streaming.
Note that these options only enable GPU acceleration for the Designer. To enable GPU acceleration for your particles back in After Effects, you will need to enable it there as well. For more information on that, see the Rendering Group page.
Preview Pane Options
Controls at the bottom of the Preview Pane affect the Camera, Render, and Playback of your preview. These changes are only affecting your Designer preview, no settings from these controls are round-tripped back to After Effects.
Camera Preview
The Comp Reset button will reset any adjustments made using Camera Preview Mode, causing the view to return to the composition’s settings.
The Camera Preview button allows you to use a temporary, virtual camera to view your form particles. Pressing your keyboard’s C key will cycle through the camera modes:
Note that these view changes are only temporary and do not roundtrip back to After Effects. To reset view changes, click the Comp Reset button. To actually change the angle or position of your form, use the Base Form or World Transform options, or use an After Effects camera.
Render Preview
The Motion Blur button allows you to preview motion blur in the Designer.
The Depth of Field button allows you to preview depth of field in the Designer. This function does not create a depth of field. It only allows you to preview the depth of field you created in After Effects. To create true depth of field, there must be a camera in your composition with Depth of Field enabled.
The Overlays button hides or shows any diagrams or visualized fields applicable to whatever parameters you're currently controlling.
The viewer with overlays enabled (left) and disabled (right).
The Full Render button renders form particles normally when enabled. When deselected, “beauty” adjustments like Size/Opacity Randomness, Blend Mode, Depth of Field, etc. that primarily affect particles’ visual attributes are disabled. This mode helps to see how particles are behaving.
The project with the Full Render button enabled (left) and disabled (right).
Playback Controls
A progress bar along the bottom of the Designer Preview pane shows the animation preview’s current position as well as the render progress when changes are made. You can control this playhead’s position and behavior with the controls described below.
The First Frame button takes your Preview Pane to the first frame of the preview's animation.
The Pause button pauses your preview on the currently shown animation frame.
The Last Frame button advances to the preview’s last frame.
The timecode next to the Last Frame button reflects the preview’s current timecode/frame. Click the timecode to pause playback and adjust which frame is displayed in the preview panel.
The Loop Playback button enables or disables playback looping within the preview panel.
The The Loop Duration is set to the composition’s full length by default. Click and enter a new duration to preview how your animation would appear at a different length. Note that you do not need to include punctuation when entering a new loop duration (i.e., a five-second clip would be 500, a ten-second clip 1000, etc.)
Lastly, the Reset Loop Duration button resets Loop Duration to its default ten-second duration.