How to Turn One Character Image into a Game Action
A step-by-step guide from uploading a character image to reviewing the loop and downloading animation files, with common input problems and fixes.
In Spritix, one character image goes through four steps: create the character, generate an action, review the loop, and download the files. A finished generation still needs a quick frame-by-frame check before it is ready for a game.
This guide reflects the product on August 7, 2026. Results vary by source image, and some images need to be cropped or cleaned up before generation.
What should the input image contain?
You can currently upload a PNG, JPEG, or WebP file up to 10 MB. The best source images have:
- one clearly identifiable character;
- the full body visible, including hands, feet, weapons, and accessories that must persist;
- enough separation between the character and background;
- a readable silhouette at the intended game scale;
- no foreground object covering a body part that the action must move.
A transparent background helps, but it is not required. A plain background is easier to remove than a detailed scene, especially when the background and the character share similar colors.
The workflow in four steps
1. Prepare a reusable character
Upload the reference, check the preview, and give the character a name. You can then reuse that character for several actions. Fix a bad crop or hidden limb at this point so the same problem does not carry into every animation.
2. Choose and generate one action
Select the prepared character and one available action. You only need to upload the character once, then you can use the same reference for Walk, Run, Idle, Jump, and Attack.
Two generations from the same reference can differ in facial detail, accessory position, limb shape, framing, or background pixels. A completed job means the files are ready to review; it does not mean every frame is usable.
3. Review the loop and individual frames
The action workspace lets you change frame count, playback speed, start frame, crop range, frame size, image smoothing, and background cleanup. Play the loop first, then inspect individual frames for sudden changes in the character or rough transparent edges.
Changing the start frame only moves the cut point in the existing sequence. Changing the speed only changes playback timing. If two poses do not connect cleanly, trim the sequence or generate the action again.
4. Download the files you need
Once the loop and frame edges look right, download a Sprite Sheet PNG, animated GIF, Atlas JSON, or ZIP of PNG frames. Each file has a different use; the export format guide explains which ones to keep for a game project.
Which inputs or results need fixing?
| Input or result | What you may see | What to do |
|---|---|---|
| Feet, hands, weapon, hair, or tail leave the source crop | Missing or reconstructed details across frames | Restore the complete silhouette and upload again |
| Another object covers the character | The hidden limb changes shape or ownership | Use an unobstructed reference |
| Background colors merge into clothing or effects | Holes, halos, or retained background pixels | Increase subject/background separation or disable cleanup and inspect the raw frames |
| Tiny character inside a large scene | Soft detail after square crop and resizing | Crop around the full character before upload |
| Extreme foreshortening or a pose unrelated to the action | Identity or anatomy drift during motion | Start with a neutral, readable reference closer to the intended camera |
| Smoke, glow, translucent cloth, or motion trails | Cleanup removes part of the effect | Inspect without background removal; export only after checking every edge |
| First and last poses do not meet | A visible snap at the loop seam | Change the trim range or regenerate; start-frame rotation alone cannot close the gap |
Six checks before download
Before downloading, answer these questions with the actual frame strip open:
- Does the face, hair, outfit, and equipment still identify the same character?
- Do hands and feet remain attached and readable in every sampled frame?
- Does the final frame return naturally to the first frame at the selected speed?
- Are transparent edges clean at both dark and light backgrounds?
- Does every frame use the same frame size and intended crop?
- Does the selected export include the ordering and timing data required by the target runtime?
If any answer is no, fix the source image, generate the action again, or adjust the loop before adding the files to your project.
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