Substance 3D Painter to Unreal Engine 5: PBR Texture Packing Guide
Optimize VRAM usage and material draw calls in Unreal Engine 5 using packed Occlusion-Roughness-Metallic (ORM) texture maps exported from Substance Painter.
Importing individual 4K resolution image files for Roughness, Metallic, and Ambient Occlusion consumes unnecessary texture memory in real-time game builds. Channel packing solves this by combining three grayscale maps into a single RGB image.
1. Configuring Output Templates in Substance Painter
In Substance 3D Painter’s Export Options, select the Unreal Engine 5 (Packed) preset. This template packs Ambient Occlusion into the Red channel, Roughness into Green, and Metallic into Blue, creating a single ORM texture map.
2. Color Space Settings: sRGB vs Linear Raw Data
Base Color (Albedo) textures require the sRGB color space. However, packed ORM maps contain non-color data; uncheck sRGB in UE5 Texture Properties to ensure linear math calculations inside your material shader.
3. Constructing an UE5 Master Material with Material Instances
Inside Unreal Engine 5, plug the ORM map's R, G, and B pins directly into the Ambient Occlusion, Roughness, and Metallic material inputs. Expose texture parameters to create child Material Instances for instant live tweaking without triggering shader recompilations.