Build crash - EXCEPTION_ACCESS_VIOLATION from loading tiles

Cesium for Unreal
1

RIS cesium crash 11-12.PNG
RIS cesium crash 11-12.PNG1857×651 157 KB

Hi, first post here. I’ve started getting this fatal error in Windows builds (unsure if it’s specific to builds or not). I haven’t found a way to trigger the error on command, so I’m not sure where it’s coming from.

I’ve experimented with the settings of the CesiumWorldTerrain actor, and I can’t say for certain, but it seems like increasing MaximumScreenSpaceError from 8 to 16 has made this crash happen less often.

Based on the above crash output, does anyone know a root cause or have suggestions on what to try to prevent the crash?

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Hi @VertexChris,

I get similar errors sometimes in editor if my computer has run out of memory. If that’s the case with your issue, than increasing the Maximum SSE would indeed help. Are you only seeing this issue in builds? Or are you also seeing them in editor? Is it possible that it’s a memory issue, or does it seem unrelated?

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Getting this error with UE 5, when trying to open most Cesium Sample project maps. Notice that the path is not identical to my UE5 installation, and using no source build.

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000142

UnrealEditor_Engine
UnrealEditor_CesiumEditor!FCesiumEditorModule::OnTilesetLoadFailure() [D:\build\U5M-Marketplace\Sync\LocalBuilds\PluginTemp\HostProject\Plugins\CesiumForUnreal\Source\CesiumEditor\Private\CesiumEditor.cpp:370]
UnrealEditor_CesiumEditor!TBaseRawMethodDelegateInstance<0,FCesiumEditorModule,void __cdecl(FCesium3DTilesetLoadFailureDetails const &),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\RocketSync\5.0.0-19505902+++UE5+Release-5.0\Working\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:470]
UnrealEditor_CesiumRuntime!<lambda_e5d2d2a778827900812ba9977b053b2e>::operator()() [D:\build\U5M-Marketplace\Sync\LocalBuilds\PluginTemp\HostProject\Plugins\CesiumForUnreal\Source\CesiumRuntime\Private\Cesium3DTileset.cpp:862]
UnrealEditor_Core

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Hi @unit23,

Are you using the latest versions of the Cesium for Unreal plugin as well as the Cesium for Unreal Samples project?

If you have an old version of Cesium for Unreal Samples, then tilesets will fail to load because there is an old, expired Cesium ion key embedded in it (we cycle keys regularly to discourage abuse). Normally what would not cause a crash, but there was an old version of the Cesium for Unreal plugin in which it did. So that’s my best guess about what might be going wrong. But if that’s not it, let me know and we can dig deeper.

Just FYI, those D:\RocketSync paths come from Epic’s plugin build environment that was used to build the plugin for the Marketplace.

Kevin

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I use the latest, UE 5.0.2 and latest Cesium Plugin. I am only able to load the first map for some reason. The plugin has been registered with my account key.

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So you just switch to the second level in the Editor, and it immediately crashes? Are there any messages in the Output Log before it crashes?

Assuming that you’re on the latest version of the plugin (v1.14.0) and that “line 370” is accurate, the crash is caused by this line:

Which would suggest that either the Tileset is invalid, or the Tileset’s world is invalid. I can’t really think of why either would be the case, though.

You’ve installed the Cesium for Unreal plugin from the Marketplace, right? And there is not a version included in your project? I think it could be worth uninstalling and reinstalling the plugin just in case something was changed or corrupted in the plugin.

It may also be worth pulling down a clean version of Cesium for Unreal Samples project, just to eliminate any problem there.

The next step to diagnose it is probably to install Unreal Engine’s debug symbols via the Epic Launcher so that we can get a more informative call stack.

Kevin

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The error log from the source folder last error is a token error (token not shown below, but is the one from my account):

Error: [2022-06-15 23:37:44.006] [error] [Tileset.cpp:1600] Received status code 404 for asset response https://api.cesium.com/v1/assets/354307/endpoint?access_token=yxcycycycyc

I can use the default project maps until I connect my Cesium account.

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Perhaps the error happens when I open maps which use Asset Depots (Boston etc) I 've not added to my account.

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Yes, you’re exactly right @unit23! I can reproduce the crash you’re seeing by using an invalid project token and then switching levels. I wrote an issue for this, and we’ll aim to get it fixed soon:

In the meantime, you should be able to work around this by either leaving the project default token unchanged, or by making sure that all of the demo resources have been added to your account from the Asset Depot and that the token you select is authorized to access them.

Kevin

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