# Display Offline terrain with Cesium Unreal Plugin

**URL:** <https://community.cesium.com/t/display-offline-terrain-with-cesium-unreal-plugin/14049>\
**Category:** Cesium for Unreal\
**Created:** [June 11, 2021, 2:15pm UTC](https://community.cesium.com/t/display-offline-terrain-with-cesium-unreal-plugin/14049 "2021-06-11T14:15:40Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Gregory\_S](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/gregory_s/32/4929_2.png) [@Gregory\_S](https://community.cesium.com/u/Gregory_S)\
**Post date:** [June 11, 2021, 2:15pm UTC](https://community.cesium.com/t/display-offline-terrain-with-cesium-unreal-plugin/14049/1 "2021-06-11T14:15:40Z")

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Hi,

i try to display 3DTiles from a local server on my machine.  
(i am a very beginner in Cesium and Unreal Engine)

- i have created a Cesium project in Unreal Engine.
- i have downloaded this sample: [GitHub - CesiumGS/3d-tiles-samples: Sample tilesets for learning how to use 3D Tiles](https://github.com/CesiumGS/3d-tiles-samples)
- i put this url in the Cesium3DTileset in Unreal Engine project:  
file:///C:/Projets/UnrealEngine/SamplesData/Test3dTiles/tilesets/TilesetWithDiscreteLOD/tileset.json

=\> A dragon is displayed.

if i use:  
file:///C:/Projets/UnrealEngine/SamplesData/Test3dTiles/tilesets/TilesetWithDiscreteLOD/tileset.json  
=\> Buildings are displayed

But if i use file:  
file:///C:/Projets/UnrealEngine/SamplesData/Test3dTiles/tilesets/TilesetWithTreeBillboards/tileset.json  
Nothing is displayed. Why ?

i have also tried to display this sample terrain of Lyon from:

> **[3DTiles-Temporal of 1st borough of Lyon from 2009 to 2015](https://figshare.com/s/f06705add7ea502d276e)**
>
> This dataset represents the evolution of the first borough of Lyon from 2009 to 2015 using an extension of 3D Tiles for modelling the temporal dimension of city models.

Nothing is displayed. Why ?

My goal is to test if it is possible to use 3DTiles Terrain offline on a local machine (and how).

Regards,

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<div class="post-metadata">

**Author:** ![Marco13](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/marco13/32/2757_2.png) [@Marco13](https://community.cesium.com/u/Marco13)\
**Post date:** [June 11, 2021, 5:07pm UTC](https://community.cesium.com/t/display-offline-terrain-with-cesium-unreal-plugin/14049/2 "2021-06-11T17:07:12Z")

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In general, you can use 3D Tiles terrain data from a local machine. Some details are given at [Adding Datasets – Cesium](https://cesium.com/docs/tutorials/cesium-unreal-adding-local-data/) , but you actually already did it correctly, by setting the Source to be a URL that points to the local file.

The reasons for the the two tilesets not being displayed are different ones:

* * *

For the `TilesetWithTreeBillboards`, it will print a message (in the output log that can be shown with “Window → Developer Tools → Output Log”), saying

> No loader registered for tile with content type ‘’ and magic value ‘i3dm’.

This just means that the tileset uses [Instanced 3D Models (I3DM)](https://github.com/CesiumGS/3d-tiles/tree/master/specification/TileFormats/Instanced3DModel), which are not yet supported by Cesium For Unreal, but will probably be supported in a future version.

* * *

For the “Temporal Lyon” data set that you linked to, it’s … a bit more complicated. The data set has some issues. For example, it declares strange transforms and bounding volumes, like

> “transform”: [1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 1841958.443, 5175950.416, 194.769, 1.0]

When “fixing” these pragmatically (with a text editor), it _does_ display something, but the result is likely not the intended one: The data set uses an extension that is called `3DTILES_temporal`. I don’t know any details about this extension, but it is not supported by Cesium For Unreal (and probably not by CesiumJS either - it seems to be a proprietary one, mentioned in [[3D Tiles] What is tileIndex ? · Issue #1039 · iTowns/itowns · GitHub](https://github.com/iTowns/itowns/issues/1039#issuecomment-472476617) , but not available under the given link…). On top of that, the glTF data that is contained in the B3DM has 14 validation errors (but these are only related to the accessor bounds - so the glTF is invalid, but could still be rendered by Cesium For Unreal).

* * *

So in general, if you have a (valid) terrain data set that uses the most common content type (namely, B3DM or composite tiles), you should be able to display it with Cesium For Unreal by just setting the URL as you did it. But when the data set is invalid or uses features that are not supported yet, you may encounter different issues that would have to be sorted out on a by-case basis.