Written by: Alisdair Araujo
In the following article, I’ll be talking about a PBR (Physically Based Rendering), how I implemented it and the things I learnt along the way.
PBR is the new kid on the block and implementing it into your workflow may seem like a daunting task. The most important thing to note for PBR is that there are two workflows. Specular/Gloss and Metalness/Roughness.
Both of these workflows use Base Color maps (Albedo), Normal maps and Ambient Occlusion maps. The key difference is that Specular Workflow utilizes a “specular texture” (argbcolor map) to control reflection amount/color, while the Metalness Workflow relies on a “metalness” texture, which is basically a black/white map where white = metals and black as non-metals. The roughness/glossiness maps are black/white textures used to control the sharpness of the reflections.
Quick tip: Turn a roughness texture into a glossiness texture by just inverting it and vice versa
Since we have an upcoming project related to PBR workflow, we used the opportunity, to do some R&D on PBR. I used Ndo to create normal maps and created the rest of the maps in Photoshop. I took the green and blue channel of the normal map as well as aspects of the Albedo to create the specular. Using the Specular map, i created a metalness map by blocking out the areas that weren't metal, example, the lights and painted warning areas. The toughest part of this workflow for me was implementing a working roughness map and I ended up spending a lot of time tweaking it to get the desired result.
Resources I recommend, which helped me understand PBR are:
● Marmoset PBR Theory
● Marmoset PBR Practice
● Allegorithmic PBR Guide 1&2
PBR is the new kid on the block and implementing it into your workflow may seem like a daunting task. The most important thing to note for PBR is that there are two workflows. Specular/Gloss and Metalness/Roughness.
Both of these workflows use Base Color maps (Albedo), Normal maps and Ambient Occlusion maps. The key difference is that Specular Workflow utilizes a “specular texture” (argbcolor map) to control reflection amount/color, while the Metalness Workflow relies on a “metalness” texture, which is basically a black/white map where white = metals and black as non-metals. The roughness/glossiness maps are black/white textures used to control the sharpness of the reflections.
Quick tip: Turn a roughness texture into a glossiness texture by just inverting it and vice versa
Since we have an upcoming project related to PBR workflow, we used the opportunity, to do some R&D on PBR. I used Ndo to create normal maps and created the rest of the maps in Photoshop. I took the green and blue channel of the normal map as well as aspects of the Albedo to create the specular. Using the Specular map, i created a metalness map by blocking out the areas that weren't metal, example, the lights and painted warning areas. The toughest part of this workflow for me was implementing a working roughness map and I ended up spending a lot of time tweaking it to get the desired result.
Resources I recommend, which helped me understand PBR are:
● Marmoset PBR Theory
● Marmoset PBR Practice
● Allegorithmic PBR Guide 1&2
From left to right, top to bottom:Color, Normal(tangent), Metalness, Roughness and Emissive.
Final output :
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