modeling large-scale brick buildings

How would one go about modeling a antique detailed brick building, like the one shown below.

It’s taken from unigine’s heaven demo

at 2:35, it seems every brick is different from the other.
Does one block out the building and then add details, or spend a week modeling different bricks and then combine them together? it seems like a huge amount of work to sculpt bricks and bake their normals to low-res bricks.

one thing you could do, is join them, and give them a displacement modifier. they would have to also have a multires modifier to make them dense enough for the displacement modifier to be effective.

I suspect that a lot of that differentiation is painted on rather than modeled and baked in. I’d block out the building, and add details.