I'm trying to work around a Redshift limitation where RS Incandescent shaders can not affect volumetric scattering.

The scene is a bunch of buildings being instanced across a grid using Point-Old Instancing with this bit of random distribution “/obj/Building_`floor(fit01(rand($PT),1,10))`/”.

I then created identical copies of each instance, with same suffix digit, same order, but kept only the polygons matching the windows with lights on those buildings. I checked, if i use a Point instancing, they line up perfectly on top of my other instances.

Now since Redshift Materials can not affect volumetric scattering, i need to use those windows polygons as source in a Redshift Mesh Light. In order for Redshift to pick up those polygons they need to be present in the scene as geometry, consequently i must “Copy Stamp” them across my scene in the same exact fashion as the point instancing does with my buildings. I brought them all into a switch using object merge nodes, threw the same script into the stamp, but referring to my Windows polygons geometries “/obj/Building_Lights_`floor(fit01(rand($PT),1,10))`/” And sadly that did not do the trick. I checked the order of the geos in the switch node, reversed that order, and nope, still won't line up.

So is there something i'm missing here please. Doesn't “”/obj/GEO`floor(fit01(rand($PT),1,10))`/" always return the same result in any context? I'm not sure what could interfere with that result.

Cheers,

A.

It might be that your geo object that is hosting the windows has been scaled or translated. I noticed that the mesh light expects the mesh it is referencing to have a unity matrix. i.e. world origin. Once I reset my mesh light geo matrix everything lined up.

Thanks for looking into it. Good to know you're getting results. On my side i haven't figured out yet why it's not lining up. But at least i know no it's a problem with my scene. Much appreciated.

Cheers,

A.