Importing sprites

The Importer turns your image files into a sprite: a single animation your pet can play, like “idle” or “walk.” You open it from the behavior graph editor (via the Assets panel) or the Object Editor’s Assets tab.

The Sprite Importer, showing the frame tray, animation preview, and import settings.

What you can import

Add frames with the tray’s Add button, or by dragging image files onto the window. Drag-drop adds them straight in as frames. The sources you can start from:

• Single Image. One still frame.
• PNG Sequence. Several PNG files that become the frames of one animation. They’re ordered by natural filename order, so frame2.png comes before frame10.png (not alphabetically).
• GIF. The app extracts each frame automatically.
• Sprite Sheet. One image containing a grid of frames. Choosing this source opens the Slicer so you can pick exactly which cells become frames; the sliced frames then flow back into the Importer. Slicing is a deliberate step: dragging a sheet onto the window just adds the whole image as one frame, it is not sliced. → Slicing sprite sheets

You can mix sources: import a PNG sequence, then append a GIF’s frames onto the end, and so on. Appended frames must match the animation’s frame size (set by the first frame); any that do not are rejected.

Frame size

The Importer reads the frame size from your first frame and expects every other frame to match it. If you add a frame of a different size, it’s rejected with an error, so keep all frames of one animation the same dimensions. The detected size is shown (read-only) in the settings panel as W × H.

There is no strict size limit for typical pet art, but smaller frames render faster and use less memory. Aim for around 64-128 px, and up to about 256 px for larger pets. Very large images (thousands of pixels) still work, but they tax performance for no visible benefit at desktop-pet sizes.

For guidance on good sizes, see Tips & best practices.

Ordering and cleaning up frames

The Frames tray lets you:

• select a frame to inspect it,
• reorder frames (move a frame earlier or later),
• remove frames you don’t want, and
• resize the thumbnails to see more or fewer at once.

The order in the tray is the order the animation plays.

Frame rate (FPS)

The Animation Preview plays your frames in a loop so you can check the timing. Set the playback speed with the FPS control:

• The default is 4 FPS, a comfortable, pixel-art-friendly pace.
• When you import a GIF, the FPS is pre-filled from the GIF’s own timing, so it plays at roughly the speed it was authored (falling back to 4 if the GIF has no usable timing). Appending a GIF to existing frames keeps your current FPS.

You can also override FPS per action later, in the node’s settings. See Node reference.

Long imports: progress and cancel

Big GIFs or large sequences can take a moment. You’ll see a progress bar with a label for the current phase (Extracting frames…, Composing sheet…, Loading frames…). You can Cancel at any time (or press Esc) to abort cleanly and start over.

Finishing the import

In the Import Settings panel:

1. Give the sprite an Asset Name (required), something descriptive like idle, walk, or jump. This is the name you’ll pick from when assigning it to a node.
2. Check the frame count and size.
3. Click Import Sprite.

The Importer composes your frames into one sprite-sheet image, saves it into your pet (or object), and hands it back to the editor, where it appears in the Assets list ready to assign.

Editing an existing sprite

Reopening a sprite shows the title Sprite Editor and an Update Sprite button; the frame size is locked so your edits stay compatible with the existing animation.