Gathering Physical Reference for PBR

If you’re working with Substance Designer, chances are you’ve tried your hand at replicating a real-life surface. Brick, concrete, wood, carpet, etc.. You’ll need reference for that surface so you’ll go on Google Images and begin your search. Getting reference for the albedo of a particular surface isn’t that difficult, but getting the roughness and normal of that same exact image requires you to be able to rotate and feel that surface. It ain’t happening. You’ll have to gather even more reference for the roughness and normal of a surface¬†that’s just like it or close to it.¬†Wouldn’t it be nice to have the reference in-hand?

Of course you can build your own photometric scanner, write all the functions to gather the light positions, generate the albedo/normal/roughness, but I’m a simple caveman. As a result, I’ve been adding to a library of common surfaces here in my office and found that it’s pretty damn cheap and easy to get all the reference you need without relying on photos. You just need to be a bit resourceful! I’ll tell you how and where I got my surfaces:

Leather

Leather1

 

Leather swatches can be found on most tannery websites. Some can send you samples for free, some do not. Restoration Hardware has a huge selection of leather swatches. They look and feel great, but best of all you get them 100% free; no shipping cost either. I pilaged 12 samples. They’re a good size too. Here is a link to the samples: Leather Samples

Hardwoods

woodcarpet

Head down to Lowe’s, Home Depot, or any large hardware store and chances are they give out free carpet and hardwood samples! Don’t forget to also pick up some ceramic tile. While not free, it’s typically not more than 1$ a tile.

Metal

Metal

While searching amazon.com, I’ve found quite a few metal samples available for purchase. Some are your plain aluminum and copper, while others are mottled and stylized. Check out the clean copper, mottled copper, clean aluminum, and the very cool zinc pack.

I’ll be visiting the local scrap yard to see what treasures await. More petina? Distressed aluminum? Old rubber?

Other Places to Pillage

In my housing development, there are many homes being built. Tons of construction materials are lying around, packaged up. In front of each property is a large wooden trash bin where the construction workers dispose of any construction waste. Yes, I’ve leaned over them to collect pieces of galvanized metal, wood planks, plywood, styrofoam, even sheets of vinyl siding. Sometimes you can find disposed concrete bricks which make great reference too.

Take a walk in the forest. Be on the lookout for any cut stumps as there is bound to be large chunks of bark lying around. Grab any large flat pieces but beware, there might be some little bugs in there. I have a big chunk sitting outside my house.

Weathering

The other advantage to collecting these surfaces is weathering. Just toss the piece in sun or in the dirt. Let it sit there for awhile and compare what it looks like now to a piece you kept inside.

Build up your collection and try to replicate the surfaces in Substance Designer. When you need to do the normal and roughness, hold them in your hand and rotate them under a white desk lamp. You’ll have to eyeball it in Substance Designer, but having it right in front of your eye is far better than the resolution-dependent internet photos.