Tileset Clipping Using a Volume

Hi,

We are needing to have the functionality to clip out areas of photogrammetry tilesets underneath building awnings or tree canopies but keeping the data above ground level visible.

Does anyone know if a tool has been made yet to address this or maybe it is an upcoming feature? If not does it seem like it would be possible with modifying the current Cartographic Polygon method to use a volume texture for it’s clipping rather than the 2D texture currently used?

Cheers!

Hi,

The current Cartographic Polygon method works by rasterizing the polygon and draping it top-down over the tileset, which is unfortunately a 2.5d method. I’m not aware of any tool that exists that could do it in a fully 3D way. However, it may be possible to edit the material to use a volume texture. You’d probably want to use the world space position, rather than the Cesium raster overlay functionality.

If you try out some methods for 3D clipping, please consider sharing the results here!

-Alex

Hi Alex,

Thanks for getting back.

A quick experiment has showed that using a volume can be used for clipping the tilesets. The test at the moment It’s a pretty basic implementation using a Box mask controlled by a Blueprint volume but it is promising as a tool, an artist could place the volume in the scene, the material is masked by the volume in addition to the cartographic polygons.

Unclipped Shop Front:

Clipped Shop Front with Volume:

For anyone else looking into this, this current setup only works for a single volume and is pretty limited but with some more development it looks promising

Hey @V2i,

This looks awesome! Thanks for looking into this. I’ll take another look at the cartographic polygon functionality. Perhaps there’s a way to use that in combination with your method to simplify multiple box masks.

-Alex

@V2i Hello! I tried PostProcessVolume, but it didn’t become transparent. Can you provide the complete code? Thank you!