What are PBR Textures?
PBR, or Physically Based Rendering, is a model of shading used in computer graphics that more closely mimics the flow of light in the real world.
The final result that we get in the material with PBR textures is also much easier to predict and much better to match with different variations of lighting.
The two most popular workflows for PBR texturing are: specular workflow and metalness worflow. Many 3d applications or game engines support both of these methods. Sometimes, however, one will focus more on specular and the other on metalness.
To create material in specular workflow you need the following maps:
- Albedo (Diffuse) Map – base color input, which is actually the most important map, giving information about the color of the object
- Specular Map – it defines the object’s shininess by using greyscale map. If you have the brighter the shade, the more light it will be reflected.
- Glossiness Map – this map decides how the object will reflect, whether the reflection of light will be more blurred or more sharp
- Normal Map – decides about dents and bumps on the object and is similar to the regular bump map but much more advanced. Thanks to the fact that it is saved in RGB format, you have an information about bumps and dents in XYZ axes.
- Height (Displacement) Map – saved in gray scale describes in which places the object is supposed to have bigger convexities and in which the creases. This is a map that actually affects the shape of the object’s mesh
In metalness workflow you will be using following maps:
- Albedo (Diffuse) Map – in the same way as in Specular Workflow
- Metalness Map – saved in gray scale describes what reflects a lot of light and what does not. The completely white color used in this map is for pure metal surfaces, and black for completely non-metallic.
- Roughness Map – works similarly to glossiness in specular workflow. It is also in grayscale and stores exactly the same information, but it is inverted. This means that the black color in this map will have most sharp shines, and white with the most fuzzy (matte).
- Normal Map – bumps and dents as in specular workflow
- Height (Displacement) Map – also used in the same way as in specular workflow.
Of course, in both of these workflows, you do not need all the maps in some situations, such as normal map or height map. And sometimes you need others, such as Ambient Occlusion or Emmisive map. It all depends on which textures object needs.
At cgaxis.com we have recently launched the PBR textures database in specular workflow. There are currently 6 collections available, and in each there are 100 textures with maps: diffuse, reflection, glossiness, normal and height. You can find there textures from such categories as: stones, wood, concrete, fabrics, wooden floor tiles and metals. Each of them is also completely tileable.
EDIT: Currently you can get 5 of these collections for only $39!
PBR textures are also available as individual products to be downloaded from our Subscribtion Plans:
Using PBR Textures
If you plan to use textures created for specular worflow, you will have to remember one thing in Unreal Engine. You need to convert glossiness map to roughness map. To do this, add between the texture map and the roughness in the material OneMinus node, which will invert the image. That means black will be white and black will be white.
In addition to this, simply connect all the other textures as usual. Diffuse map for Base Color, reflection for Specular and normal for Normal.
In Unity, to create PBR material using specular workflow, you have to change the shader of the created material to Standard (Specular setup). Due to the fact that there is no separate slot for Glossiness, you will need to use the Alpha channel in Abledo or Specular maps. All you need to do is to paste the glossiness map into the alpha channel in the specular map in any 2D editing application.
After that add this map to the Specular slot. Then the diffuse map to the Albedo slot, normal to Normal and height to Height.
3ds max and V-Ray
If you use 3ds max together with V-Ray, in the material editor create a regular VRayMtl. Then add diffuse, reflection and glossines. In the bump slot, add VRayNormal map. Inside it on Bump Map, load the Normal map. You can also add a VRayDisplacementMod modifier to the object with the Height map as Texmap.
You can also use PBR Textures to create your own with Substance Painter and load it as a stencil or fill layer. Just insert all maps into appropriate slots. Remember also to set at the beginning which workflow you want to work – whether specular or metalness.
The use of PBR textures provides more coherent, realistic and predictable results. It also works well under different lighting conditions, and thanks to normal and height maps you will get a satisfactory effect without the need to model some details. Therefore, regardless of whether your work is related to the game industry or architecture, it is worth knowing what benefits Physical Based Rendering gives you.