Hey, im new in using Unreal Engine and started with a car visualisation project in UE4.
Im using the Automotive Material Pack from Unreal and i cant figure out, why my “Glossy” reflection behaves like it does in the picture. I have a HDRI Backdrop in my scene, also the car geometry and a plane with a megascans texture as a floor.
The yellowish glossy reflection seems to reflect the bottom of the HDRI, which is some kind of sand but in the scene there is asphalt everyehere on the bottom.
You can see the asphalt reflect in the door but the glossy looks like there is no asphalt.
What could be the problem here? Im Using unreal 4.26.1 with raytraced reflections on, and denoiser off.
One thing you can check, is go into your post process volume (if your scene don´t have one, then drop one into your scene ^.^), search for the raytracing reflection settings, and there is a slider for max roughness (default value ~0.60). Raise this to 1 and check, if something changes. With this slider you define, which roughness values will use the raytraced reflections, and which use cheaper methods like reflection captures or the skylight captures. Anything below this max roughness setting will use raytracing, everything above will use whatever backup solution Epic had installed.
And while you are there, you also may raise the max bounces to 3.
thanks for your help! i raised the max roughness to 1, the scene looks nicer so thanks for your tip, but unfortunately the problem still existst.
when i change the lighting to a skylight and a directional light it seems to work so maybe it has something to do with the hdri backdrop?
when i set the lower hemisphere to a solid color (black) in the hdri backdrop skylight the yellowish glossy color disappears and it looks ok but that means, that he really doesnt care about the megascans plane on the bottom…
How much are they away from each other? Is it possible to put this mesh closer to this ground plane, so that it basically stands directly on that ground? Not that your door mesh (or whatever part of a car that is) is just way to high, so that the reflected rays cannot hit the ground plane.
