How to make OSM buildings w CesiumIonRasterOverlay less shiny?


I’m using OSM buildings with the CesiumIonRasterOverlay:

For my taste I would like to have the buildings less shiny, I wanted to tone down Specular/Metallic and/or increase Roughness.

I followed the materials for Overlay0 and ended up at ML_CesiumRasterOverly, and found that Metallic/Specular already is set to 0 and Roughness to 1.

Clearly I’m missing something here, how can I change the material to get less shiny OSM buildings?

As a bad hack I can go to the base material and set it to full roughness:

This works in a way, have a look at the screenshot below, but I don’t want to go this way, I’d like to have more control.

Any help appreciated,
thanks & best

The metallic/specular/roughness properties of ML_CesiumRasterOverlay won’t matter, because the material layer blend used with overlays by default, MLB_CesiumAlphaBlendBaseColor only blends the base color (as the name implies), not any other property.

In the default MI_CesiumThreeOverlaysAndClipping material instance, the metallic/specular/roughness properties come from the background material layer, ML_CesiumGltf, and it in turn uses the values from the glTF.

So, the solution here is to copy MI_CesiumThreeOverlaysAndClipping into your project and add an extra layer at the top of the stack to override the properties:

The ML_Nothing and MLB_NotShiny are a simple material layer and material layer blend (respectively) that I created for this purpose:

ML_Nothing is just a default material layer (no changes):

MLB_NotShiny ignores the top layer, passes through the bottom layer, and modifies the properties we care about:

Then just set this new MI_NotShiny as the Cesium → Rendering → Material property of the Cesium OSM Buildings tileset and this seems to achieve the intended effect:


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Hi Kevin,

as I wrote, I was missing something - thanks for the lightning-fast and super-helpful reply! The OSM buildings with raster overlay are really nice for flight simulations if you don’t get too close to them. Makes a huge difference to see a skyline passing by in the distance in comparison to just having terrain with satellite imaginary (that still looks cool at higher altitude on VFR flights, I’m not complaining!).