Blank tiles around my Raster Overlay


I am just starting to implement Raster Overlays in my current project and am extremely excited about this functionality. I’ve run a first test wrapping my satellite image over Cesium World Terrain and what I’m experiencing is blank tiles around the edges of my image, I assume it’s somehow preventing the Bing imagery from loading at this distance. The Bing tiles do start appearing when I am very close to the ground, however it is key for me that the Raster Overlay appear seamlessly from any distance.

Is there a way to troubleshoot this or a possible workaround? Would really appreciate any ideas.

Hi @agatanc,

It’s possible that those borders actually exist in your satellite imagery. What sort of tile server are you using? Is it serving JPG files or PNG? JPG files do not support translucency, so the server may be filling with a solid color.

I’m guessing your Bing overlay has a Material Layer Key of Overlay0, and your satellite imagery overlay has a Material Layer Key of Overlay1. Is that correct? If the server is in fact producing solid-color borders, you should be able to create a custom Material that turns a particular color into an opacity mask. This tutorial should help you understand how to create Materials for use with Cesium for Unreal:


Hi Kevin,

Thank you for your reply! I uploaded the image through Cesium Ion, it’s a TIF and I can confirm that the extents visible in the above screenshots are correct. It also shows correctly in the ‘My Assets’ preview - see image below:


Both the Bing overlay and my image had in fact their Material Layer Key set to Overlay0. I’ve just changed my imagery to be Overlay1, but this hasn’t resulted in anything just yet.

The issue seems to have gone after restarting UE5 :slight_smile: I should have done that sooner. Thank you for your help!