Answered: Megascans Studio / Layer blending question
polycounter lvl 10
Let's say you're trying to author a 4x4 or 8x8 concrete surface for large architectural objects by mixing a big set of layers from 1x1 or 2x2 scans. The main problem you have to solve is repetition. In PS, it would be a fairly simple (but somewhat irritating in terms of mask syncing between different PBR map sets): you'd just render out some tiled noise (e.g. Clouds), push the constrast of it as necessary (e.g. almost to black and white point, creating sharp islands occupying roughly half of canvas area), and use the result as a mask for a layer. Then create another mask for another layer on top, and so on, and so on. You'll very quickly hide any repetition that way. And if you want to hide repetition with just one source image, you can just offset and rotate it's copy, and blend it in using the same kind of independent noise.
With Megascans Studio, you have a bit of a problem trying to get the same result. There are two ways to blend layers: one is to use the scanned height, and another one is to use height noise. The first method is immediately out - since the height data for all layers is exactly the same for all tiled cells, the end result would be exactly the same on every tile, keeping the repetition fully in place. Height noise has a bit of an issue, though: it's hard to blend layers using large, low-frequency islands without introducing huge hills into the height and normal maps. A surface for something like a concrete wall should be almost perfectly flat, but any height noise intense enough to punch through scanned height with low-frequency tile independent features will also introduce huge low-frequency bumps to all maps.
Is there a way to blend layers without distorting their height, basically masking them away without pushing the height at all?
With Megascans Studio, you have a bit of a problem trying to get the same result. There are two ways to blend layers: one is to use the scanned height, and another one is to use height noise. The first method is immediately out - since the height data for all layers is exactly the same for all tiled cells, the end result would be exactly the same on every tile, keeping the repetition fully in place. Height noise has a bit of an issue, though: it's hard to blend layers using large, low-frequency islands without introducing huge hills into the height and normal maps. A surface for something like a concrete wall should be almost perfectly flat, but any height noise intense enough to punch through scanned height with low-frequency tile independent features will also introduce huge low-frequency bumps to all maps.
Is there a way to blend layers without distorting their height, basically masking them away without pushing the height at all?
Replies
I would prefer not to do this manually in PS, but so far I had no luck achieving similar results with Megascans Studio - going for large low-frequency masks like those inevitably adds huge bumps to the normal/height data.