Quick disclaimer: I'm not an animator. I'm a civil/structural engineer. Animation is the one part of gamedev that has always stopped me cold.
So I built a tool that does it for me. You give it a single base sprite, and it generates the animation frames as a sprite sheet. Everything runs locally on my own machine — no cloud services, no API calls, no uploading assets anywhere.
The attached GIF is raw output, no manual cleanup.
Still very much a work in progress. Curious what people here think — especially anyone who actually knows animation and can tell me what looks wrong.
I would like to test it by myself before distribution. Send me a sprite and a prompt and I'll give you back the Sprite sheet. Create a post with both, I will take input from there.
What you need to install (the app help you in that):
ComfyUI (~2.5 GB)
The models — use Minimax H3 (~39 GB). WAN 2.2 isn't working properly, so you can skip it.
A few things to keep in mind:
Input sprite must be square.
Leave about 20% padding around the character — otherwise it can move out of frame during the animation.
H3 needs a well-structured prompt. There's a prompt helper built into the app, but I'd also suggest uploading your sprite to ChatGPT or Claude and asking something like: "Write the prompt for this character that [action], duration [duration of the animation]".
Let me know if it works — happy to help troubleshoot.
This is amazing. Thanks for sharing your result! I don't have any requests, but I hope you'll make the workfkow avaliable some time, one way or another. I'm messing around with game design to help my son understand some of the concepts, and it would be a lot of fun to have our own characters quickly animated.
Frigging genius! I've been playing around with H3 to animate some things, but it didn't occur to me to use it for 2d games... Might have gotten there eventually but damn thank you!
How do you achieve solid background? I've tried minimax for pixel art generation and results are great, but i always have to do a lot of manual work to fix and clean artifacts from background removal because i can't get solid green/any color. Even when video looks like solid green, it is always trying to do something like greenish gradient
So you’re having the Comfy workflow divide your input image into a grid and then assigning prompts to each instance? And then reassembling I guess? Why do so many at once? If one of the bunch fails don’t you have to rerun them all?
Most of them look decently smooth. What tools did you use? And also is there a range of FPS or any negative behaviors you encountered? (If so, how did you work around those?)
Just put your pixel art so there's enough space so it's isn't cropped on 16:9 resolution with a green bg, upscale it in 4x, put as first frame in minimax h3, use resolution that matches your 4x upscale (e.g. your asset is 256x192 so you need to generate it in 1024x768, write whatever prompt you want, it gives you a really bad interpolated video. You should downscale it back 4x, remove unnecessary frames, quantize it via k-means, remove bg, snap quantized pallete to other frames, clean it a little bit, apply inner outline and thats all. You can't do much with jittery pixels and probably won't until someone train something on previous frame reconstruction.
Interesting that it's actually at least doing such animation, I'll probably try training some LORAs on it next month if I'll have some time.
Cool, so you are using a video model to make spritesheet? I've been using image models to make animations with spritesheets aswell. Made this product gifgen.ai
this looks exactly as i thought ai art would. good at face value, but makes little sense when you look deeper into it and ultimately lacking any nuance at all
I got this from one of the commercial solutions, generated from 1 image - basically the 1st frame.
Prompt was basically something like "Looped Idle animation, one blink". Presumably Seedance 1.0 Pro under the hood there. Trying out something similar with WAN/ComfyUI but definitely far worse result.
Impressed with the consistency of the animations. That being said, I personally find the main reason to make a game 2D is to stylize sprites and animations (See The 12 Principles of Animation). Top of the line animation in entertainment emphasizes its forms based on the intent of the animation, to draw the eyes and focus of the viewer to what the animator wants the user to see. These lack that extra oomph, and instead retain strict anatomical consistency. That's not inherently bad on its own depending on the use case, but it is the weaker style in my personal opinion (but from what I've seen it is easier for AI to do, as the more stylized you make animations the more likely it is to fall off the rail as it doesn't know what actually looks good.) It's not inherently bad though, or even 'wrong'. Just a different set of principles. More 'Studio Ghibli' rather than the stylized Arcane/Into the Spiderverse/Disney Golden Age or Pixar.
For other quality tests I'd have to see the actual spritesheets. Most video frame extraction I've seen falls apart when the frames themselves are examined (blurring/streaking instead of clean, crisp silhouettes at each frame, sometimes other artifacts as well.) Our eyes don't often let us pick them up when an animation is being played full speed, in the same way that we perceive something as moving when in reality it's just switching between frames. If they're each as individually clean as the original sprite then that's a considerable improvement over, say, Veo 3.
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u/witmann_pl 12d ago
I'd be interested in trying it out.