Hi I am still adapting to PBR and biting it from different angles. ;) My today's question is maybe simple. Why use metallic texture to differentiate metal parts from non-metals when I can do this by albedo + spec map. Why it's better using metalness map instead specular map? Is it better only because it limits possible…
This tutorial explains the differences in detail, and how to convert between metalness and spec maps: http://www.marmoset.co/toolbag/learn/pbr-conversion General pbr: http://www.marmoset.co/toolbag/learn/pbr-practice In short, spec maps are more flexible, but with the added flexibility comes a lot of freedom to make very…
PBR need a lot more calculations than a simple phong shading for example. A phong only does dot products between different vectors and multiplies/powering them with thing like diffuse map/specular map/gloss map. Now very basically, pbr need to distort the reflection source (usually cubemaps) properly to the given surface,…
My guess it requires more real time calculations while before all the values were taken straight from the textures. Not sure but we probably don't see PBR on cell phones and tablets because of that exact reason. Although I don't see reasons why we can't bake shader tree in all necessary texture inputs even with such…
I'd say it's better in the regard of using less memory. It's most surely an optimization as much as a unified and simple workflow to get a "correct" look. Instead of having a full RGB texture to define if its metal and what color. Now you can settle for 1 channel and fetch the metals color from the Albedo instead. Also…
With the metalness workflow, the metallic texture defines where you have 100% reflectivity (metal - white) and 4% reflectivity (non metal - black). The albedo is just defining the color or the reflection, and not the intensity of the reflections. So if you want gold for example, then first you need white in your metallic…