@marcatore Yes, should be possible, however this will require at least one more mesh segmentation at road border as you may guess, vertex colors apply on vertex and we cant rely on base mesh.
@bluecd Archipack addon plans are driven by needs and as i’m lazy when it comes to modelling i try to make this job as easy and fast as possible. On the other hand, majors actors in the archviz industry are money driven projects, leading in half working solutions, pretty slow and painfull workflows.
Got some projects in the boxes (Enhanced 2d export, general cad io, energy / lighting simulations) , but will try to focus on archviz / prototyping workflows and parametric objects improvements first.
Some of those projects require things blender is not even able to handle - eg Open cascade nurbs processing as in ifc import / export, so not even certain it will be possible / doable / not silly at all.