View Full Version : 2018.0.2: Unaffected by Fog - not working

03-12-2018, 02:03 PM
I need my scenes to have the backdrop unaffected by fog. I'm using a full sky/ground HDR equirectangular image in Backdrop > Textured Environment. Enabling "use backdrop" in fog properties does not produce the desired result, because then the clouds in the image "bleed" through my mountain terrain mesh, which, obviously, is unacceptable. They are supposed to OBSCURE the clouds, not become blended with them!

So, because there is no "Unaffected by Fog" option for backdrop images, I have to add a sphere object, mapped with the same HDR image, and set it to Unseen by Rays, Unseen by Radiosity, and Unaffected by Fog. However, Unaffected by Fog is NOT working... the sphere is STILL being affected by any mode of Fog. I NEED the full fidelity of the backdrop or sphere mapped HDR image. I achieve the best environmental results when I add Fog to the terrain mesh only, setting its Max Distance to get an opacity/thickness that blends nicely with the unaffected sky.

Is this a known and reported issue? Forum search sucks, or it didn't return any topics with "unaffected by fog" in the title.

03-13-2018, 10:32 AM
Hacky workaround until fog flags in 2018 are fixed: because it only involves a single object, I added a distance to camera gradient on color (using alpha keys and placed above the image map layer), luminosity, and diffuse of the terrain mesh's standard surface. The last two reduce diffuse to 10% and lum. to 70% at desired far distance, in order to fade out bump map and self shadows. Looks rather indistinguishable to fog.

I will probably keep these texture additions, because it eliminates the need to have a sky mapped environment sphere set to unseen by rays and radiosity, in order to clearly see the sky that is otherwise obscured by fog over the textured environment backdrop. The environment light still needs to have the sky map in the textured environment backdrop.