Aight a roughness map controls how smooth or rough a surface appears by affecting specular reflections (the shiny reflections you see on materials). It is a grayscale image, where:

Black (0.0) = Completely smooth → sharp, mirror-like reflections

White (1.0) = Completely rough → dull, scattered reflections

Gray values in between control the transition.

Think of roughness like the "frosted glass" effect—frosted (rough) glass blurs reflections, while clear (smooth) glass reflects like a mirror.

In CS2 (Source 2), specifically...
Source 2 uses a Physically-Based Rendering (PBR) system. The roughness map is a standard part of PBR materials.

You’ll typically define your roughness map in the VMT (Valve Material Type) or through the material editor, like so:

vmt
Copy
Edit
"roughnessMap" "materials/your_path/your_roughness_map"
Or, in the Material Editor UI, you'd plug it into the roughness input slot.

How to Make a Roughness Map
You can make one in Photoshop, GIMP, or any image editor, or generate it using tools like Substance Painter or Materialize. Here's how:

Method 1: Manual Creation (simple)
Start with your base color or a grayscale version of it.

Adjust contrast/levels to highlight where you want shine:

Metal/Polished areas → Dark

Fabric/Wood/Rough concrete → Light

Save the map as a grayscale image (usually PNG or TGA).

Method 2: Use a Tool (recommended)
Materialize (Free tool): Automatically generates PBR maps (including roughness) from your base color or height map.

Substance Painter/Designer: Professional tools that let you paint and preview roughness live.

Tips
Avoid overdoing contrast unless your material needs extreme gloss/roughness.

If using Photoshop: Use the Levels or Curves tools to dial in smoothness zones.

The roughness map should ideally match your normal and color map visually—e.g., a scratch in the normal map should appear slightly smoother or shinier in the roughness map.

Test in-engine to see how light reflects and adjust accordingly.
Example Use Cases
Material Type Roughness Value
Shiny plastic ~0.2 (dark gray)
Matte wood ~0.7 (light gray)
Smooth metal ~0.1
Brushed concrete ~0.6–0.8

hope that helps @Jack bob

引用自 sMOKYuSP：

hope that helps @Jack bob

Thanks so much! It very much does!