Hi team, I’m observing unexpected behavior in my C extension (Rayscaper) regarding SDK version compatibility. I built the extension against the SketchUp 2026 SDK (2026-0-429) but ran it in SketchUp 2024. It appears that the SURefType enum changed in a non-backward-compatible way between these vers…

If we fix this now, I’m afraid we will rock the boat even more. Unless you are willing to drop support for 2025 and 2026.0, you’d also have to deal with 2 breaking changes. So our current conclusion as a team is to: Add tests internally to prevent this from happening again. Document what happened …

[image] pixelcruncher: As you can see, the SURefType_Environment and SURefType_Environments values were inserted before SURefType_Face, which shifted the enum values and broke backward compatibility. When running on older SketchUp versions, this results in incorrect type interpretation. Dang…

Ugh.. very sorry about this @pixelcruncher . We rely on code reviews to catch ABI compatibility issues and things slip through sometimes. Now this is a bit of a dilemma; if we moved the new enumerations to the end, we might further cause issues for code that already built it this way (though the lik…

@bugra Thanks for the quick response! Ugh.. very sorry about this @pixelcruncher . We rely on code reviews to catch ABI compatibility issues and things slip through sometimes. Now this is a bit of a dilemma; if we moved the new enumerations to the end, we might further cause issues for code that a…

Thank you for the detailed context Thomas. I agree that we need to do something about this. The problem is SketchUp C API can also be used in what we call the “live” context, which is by calling the APIs exported from the executable rather than the DLL, which is necessary in order to be able to act …

This is further complicated by the fact that this change was made in 2025 actually (not 2026) I don’t know if you never supported 2025 (?) I suppose no other developer is relying on the integer values of these enumerations since we never heard of this. But this was certainly a mistake that we try …

[image] bugra: Thank you for the detailed context Thomas. I agree that we need to do something about this. The problem is SketchUp C API can also be used in what we call the “live” context, which is by calling the APIs exported from the executable rather than the DLL, which is necessary in order…

So basically there is a “breaking change” support line between 2024 and 2025. Live C API Extensions would need to sniff the version on the Ruby side and branch to load the proper DLL or SO file that was built with the matching SDK version. Either this or publish separate extension editions pre-202…

This is how I plan to work around this issue. Pack 3 Rayscaper DLLs into a single RBZ file, then load the correct DLL based on the SketchUp version. I’m not keen on sniffing out differences on the C side or manually translating enum values. Either this or publish separate extension editions pre-20…

In the end, ya’ gotta do what works for your system.

SDK Compatibility Issue: SURefType Enum Change Between 2024 and 2026 SDKs

Developers SketchUp SDK

pixelcruncher October 31, 2025, 5:40pm 9

@bugra Fair enough, I understand that fixing this will cause even more collateral damage. I will work around this in my own extensions. Thanks!

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SDK Compatibility Issue: SURefType Enum Change Between 2024 and 2026 SDKs

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