I discovered that my curve editor was showing inaccurate curves. I discovered this in the most backwards way possible—by creating curve preview buttons and noticing discrepancies between the curve previews and the curves shown in my custom runtime editor. This is turning into a vibe coding mess! My confidence waned after I read comment after comment in this thread about other users of Claude also noticing its poor performance over time. To be clear, this is something I first noticed with Sonnet 3.5, and each LLM I’ve used since its release (Gemini 2.5, Claude 4) has faced a similar degradation of performance the longer its been available. What an insane demand for compute we have in today’s world! I’m a drop in a massive ocean.
Anyways, my curve editor kinda works now, but the curve gets re-interpolated after every edit to match Unity’s AnimationCurve format. Also, there’s no changing of the tangent type yet. It’s not ideal, but I’ve built this house on top of a murky water and my intention was never to code this myself. Check it out:
I wouldn’t be a 10x vibe-coding dev if I didn’t have multiple agents going at the same time. Once I noticed the aforementioned curve editor getting hairy, I started to build another one, this time with GPT 5. To (hopefully) give it better context, I used ILSpy to pull the source code for Unity’s CurveEditor from UnityEditor.dll (thanks Reddit) and included it with my original prompt.
Behold, Reader, as I replace one broken system with another!
The cool thing about this one is that it 100% works directly as an AnimationCurve, something I didn’t know was possible. The problem is that GPT 5 is completely shitting itself with any of the UI edits. GPT 5 doesn’t seem to want to use log debugging unless I specifically request it. I’m utterly embarrassed that I haven’t found the bandwidth to address these UI issues myself. I’m stuck in a downward spiral of re-prompting. Still, I can’t help but feel like this is already better than the system I’ve spent the past two days on.
I reverted my Cursor history up several chats to a place before my agent starting going dumb on me and then added back a few of the successful fixes I learned about during those extra chats. I don’t even have it in me to add this thing to GitHub tonight. Let’s give it another go when I’m recharged.
To recap, this ChatGPT runtime curve editor project is suffering in the UI department. The curve preview doesn’t show, or if it does show, I’m unable to distinguish it from the curve editor window (since neither are fullscreen). Also, the curve editor UI never shows. Maybe since Claude seems to handle Unity document UI challenges well, I’ll pass those tasks over. I definitely think this system is the winner even if it’s not looking right yet. The curves I edit and create are actually AnimationCurve curves, not some alternate that needs to constantly be converted after an edit.
Tags: unity animation chatgpt claude debugging vibe-coding ui