Excerpted from and compiled from the Unreal official tutorial: https://learn.unrealengine.com/course/2449699
Project file download in the course:
Link: https://pan.baidu.com/s/1o7m3pR7BvaCYAmlx57B9HQ Extraction code: uenb
1. Introduction of PBR material
Physical Based Rendering (PBR): Physically based rendering. The most important inputs for physically based materials are Metallic, Specular and Roughness
1. Base Color:
The color of the object itself, usually linked to the surface texture of the object, RGB input. It accepts Vector3 (RGB) values and each channel is automatically clamped between 0 and 1
2. Metallic color:
Controls how "metal-like" the surface is. The Metallic value of non-metal is 0, the Metallic value of metal is 1, the default is 0
- Metalness 1 to 0 changes:
3. High luminosity: Specular:
Describes the ability of the material to reflect light, the default value is 0.5
Official definition: When editing a non-metallic surface material, you may sometimes wish to adjust its ability to reflect light, especially its specular properties. To update the specularity of a material, enter a scalar value between 0 (no reflection) and 1 (full reflection).
When the value is 0, theoretically the material will no longer reflect any light, and there will be no more reflections
- Specular 0 to 1 variation:
4. Roughness: Roughness:
Describe the roughness of the material, which will affect the reflectivity of light on the surface of the material, the default value is 0.5
When the value is 0, it means that the material no longer has roughness and is quite smooth, and the effect will be similar to specular reflection
When the value is 1, it can be understood as complete diffuse reflection
- Roughness varies from 0 to 1:
Material Blueprint Node:
2. Simple production of PBR material texture
Take the "wooden door" model in the course project as an example:
1. Make the base texture
2. Make metallic texture
Paint the metal area white (1.0), and the non-metal area black (0.0). Because of the metalness node, connecting 1 means complete metal, and connecting 0 means non-metal, you can mark the metal value of the material according to different areas.
3. Make roughness texture
Convert the base color image into a grayscale image, and then invert (bright to dark, dark to light), you can get a simple roughness texture.
It works because:
If the color itself is bright, according to the principle of light reflection, it shows that it has a stronger ability to reflect light, which is equivalent to a very low roughness;
If the color itself is dark, it means that its ability to reflect light is weak, which is equivalent to high roughness.
