Inverted mask to help create easy room floors

Hello

I am creating rooms randomly in my project, and have now hit an issue and I'm running out of ideas on how to achieve my desired effect.

I'm not so great with shaders but I feel like this is a job for a shader...

So, my entire area will share the same floor texture using a plane that covers all the created rooms.

I would like make the floor texture only visible within the walls of these rooms, but as you can see in the provided picture, I have managed to do the very opposite of what I intended to do!

Within each room, I have a mesh that outlines the room's shape (highlighted in the screenshot), maybe I can use that mesh to mask or occlude the floor plane? can someone share some ideas on how to achieve that?

Thank you!

 

unless there is organic terrain you can simplify this for flat floors in shaders, so no need for outline +another floor
[I assume floors are a flat]

tiling is WorldSpace casting UV's in the world_Y direction
All receive repeating texture based on position

object position -> world position -> cross product [establish vector] * float2 [# of texture repeats in world]



might be ways to do this cheaper; but this is my level of CG math

 

That seems like a way simpler solution than what I had in mind.

Now to convert the idea to a shader since I can't yet use shader graph thank you for the suggestion I'm gonna give it a go!

 

object transform is not needed now that I look/think again

Position(world) -> cross product works

 

Thank you!