BUILDING BETTER TEXTURES
Josh Lynch reveals how to create realistic brick albedo in Substance Designer
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Josh Lynch reveals how to create realistic brick albedo in Substance Designer
Over the last couple of years, Allegorithmic’s Substance Designer has quickly become a standard in the industry. For this breakdown, I will not only cover how I created the albedo map for this texture, but also how I approach creating a material, what I look for in reference, and how I take this reference through to render.
I made this Sloppy Brick Wall texture for a personal project. I wanted to push myself to see what was possible in Substance Designer on a few key things. The first was getting mortar to feel like it was dripping out over the bricks. Second, to get a nice surface feeling of old brick. Lastly, I wanted to create a beautiful and layered albedo map that felt as close to the reference as I could get it.
Before I go into a breakdown of how I made the albedo map for the brick shown in the render, I wanted to give some high-level notes about how I treat my albedo creation process for most of my materials. When using Substance Designer, you are trying to take data that’s driven by maths and create a believable result while trying to avoid a procedural look. So in order to combat this, I use a lot of Histogram Shift and Histogram Scan nodes in conjunction with Warp and Directional Warp to create more unique-looking data.
I also cannot stress enough how important reference is. Finding some online is great, but going out and taking your own reference is even better because you get so
I cannot stress enough how Important reference Is. taking your own pictures Is best Josh Lynch, environment artist, Infinity Ward
When creating albedo maps, It Is best to use colour calibrated reference or scan data to get proper luminance values for the material
much more from seeing it in real life. You should always be looking at reference. You can’t make the stuff up in the reference, so it is best to be constantly checking it while you are working.
When using reference, I identify major forms and specific elements to bring over when creating the material. Materials need to read from long, medium and close up ranges. When accounting for this broad range, I think of it as macro to micro, covering all possible viewing distances. I try to work large to small, but it’s not a hard and fast rule. For me, it is more about accounting for the detail than working in a certain order.
When creating albedo maps, it is best to use colour calibrated reference or scan data to get proper luminance values for the material you are trying to create. This will help ensure believability and consistency across the scene you are working on. In addition to using this data to get luminance values, reference data can be used as inspiration for colour variety and detail placement.
Getting Started
Once it is time to create the albedo map, I will have already established the height and normal maps, along with the first pass ambient occlusion and roughness maps for a sense of grounding. These maps are created prior to doing any work in the albedo because it is crucial to get a material looking and feeling realistic in terms of surface read (height/normal), lighting response (roughness) and sense of depth (ambient occlusion). I only create the albedo after these other maps have been established.
One of my favourite things about working in Substance Designer is that I am able to leverage any existing masks that were created when building out the height/normal maps, as well as Curvature and Ambient Occlusion nodes for masking and detail purposes, and use that data to help build my albedo. This is great because it ensures that my albedo will work with my height/normal map, which creates a far more pleasing end result.
Material Separation/ 01 Brick colour Variety
As I mentioned previously, I like to work on the ‘big read’ or ‘thumbnail level’ of details first. To start off the albedo, I use the same mask that provided separation for the gloss/roughness maps to separate the bricks and mortar for the albedo.
To start, I sample colours from calibrated data and apply that via uniform colours to the stones and mortar – see image 01a.
Bricks are not always the same hue or value and a flat colour is really boring. For the next steps, I apply some hue and value variety to the bricks, while keeping the mortar a flat colour. In order to get variety and interest, I leverage a multi value greyscale map in conjunction with Histogram shift and Histogram scan nodes. This set-up allows me to quickly make masks to isolate a select amount of bricks where I want to add variety to the brick colours. I really like this workflow as it is extremely flexible and iteration is very fast.
To get some subtle value variety throughout the array of bricks, I leverage the multi value greyscale map by plugging it into a Blend node set to Overlay at a very low opacity. It is important to not only provide contrast in hue and saturation but in value as well.
Now that large-scale brick variety has been established, I start to add the secondary brick interest from the reference. First, I darken the edges where the damage occurred. A great, non-destructive way to do this is by using a mask and HSL (Hue, Saturation, Lightness) node. The HSL node takes the data being plugged into it and modifies it, ensuring a smoother workflow with less upkeep when changes are made later on. See image 01c.
I also work in some local colour variety via secondary hue and value shifts to give some more interest to the bricks. A great way to do this is to take grunge data and scatter it around with a Directional warp that is driven by the multi value greyscale map. This is a great way to not only scatter data around but it also makes the bricks feel unique next to each other and creates a more believable and organic result.
“push saturation a bit more than you think you should. Harsh lighting from the sun or intense light sources tend to wash out colour. you can also pull back saturation in engine much easier than you can add saturation back in,” says Josh
creating a Sense of 02 Story on the Surface
Now that I have established large reads and local colour variety within the bricks, I start to work in surface details on the bricks. These include details such as collected dirt, dust and surface staining. See image 02a.
When adding in detail such as collected dirt, I use Curvature and Curvature Smooth nodes that run through a Blend node, then a Levels node to create a mask. I then use this mask along with some noise and a uniform colour to create the dirt.
With that same mask, I apply a subtle value increase to make the bricks appear slightly worn and faded, this adds a touch of contrast, which goes a long way.
Now that there are some elements of wear and age, I go in and add some stains and dirt. Employing some of the previously discussed node set-ups, I add more interesting elements that I found in the reference, such as stains, dirt, globs of paint and some splashes of mortar that made their way onto the bricks – see image 02b.
These elements are crucial to making a material that not only feels grounded, but also helps to sell the fact that there is a believable history behind the wall.
For the final touches to the bricks, I bring in some more elements of splashes of mortar and splashes of paint to really bring the brick wall to life.
adding the 03 final touches
Up until this point, I have spent a lot of time and effort focused on making sure the bricks feel believable. However, I haven’t spent much time on the mortar.
For the mortar, I like to keep it simple for aesthetic reasons. There is already a lot of noise and interest in the bricks, so adding a lot of noise to the mortar would hinder the balance of the read. I usually add just a simple dirt stain, but I also really like to add some dust to give a sense that these bricks have been out in the world for a while. When creating something like dust, I like to take advantage of the RGBA Split node to create a mask isolating the upward facing portion of the mortar. This helps to lend a sense of gravity to the material.
In addition to the directional dust, I also add a subtle layer of dust to the tiling texture to help ground it a bit more.
I hope you’ve found some good tips and ideas when it comes to building better textures. As you can see from the final albedo, there is zero lighting information baked into the texture, which is key for PBR shaders and lighting.
Again, one of the major benefits of the Substance Designer workflow is the speed at which an artist can create and iterate! With the software’s non-destructive workflow, it opens the door wide open to exploration without fear of losing work. More freedom to explore ideas often results in a higher-quality product in the end.
Many of the philosophies, workflows, and tips covered in this tutorial can be used when creating a variety of material types. I hope this breakdown has been informative for you and thanks for taking the time to check it out!