Export Textures for Unity HDRP

This guide covers the Unity HDRP destination on Export Texture and the matching source on Texture Folder. The files are written for HDRP’s Lit shader, which reads one Mask Map instead of separate metallic, occlusion, and smoothness maps. For the Built-in render pipeline or URP, see Unity Built-in and URP.

Setting	Value
Destination	Unity HDRP
Filename Template	{name}_{channel}
Normal Convention	OpenGL
Height	Unsigned container

Files written

Shown for a set named oak_bark with all eight roles (how to read these tables). A set with fewer roles writes fewer files.

File	What it holds	Container and depth	Encoding
oak_bark_BaseColor.png	Base Color in RGB, the set’s cutout in alpha	PNG 8-bit	Color
oak_bark_Normal.png	Normal	PNG 16-bit	Packed normal, OpenGL
oak_bark_Mask.png	Packed: R Metallic, G Ambient Occlusion, B detail mask constant 1.0, A smoothness (1 minus Roughness)	PNG 8-bit	Linear data
oak_bark_Height.png	Height, remapped into 0 to 1 when it runs outside it	PNG 16-bit	Linear data
oak_bark_Emissive.png	Emissive	PNG 8-bit	Color

The Mask Map lanes

The lanes are HDRP’s own: red metallic, green ambient occlusion, blue detail mask, alpha smoothness.

The blue lane is a constant 1.0 on purpose. HDRP uses 1 to display a detail texture and 0 to mask it, so a constant 1 means a detail map assigned later shows in full.

When no Mask Map is assigned

HDRP’s separate note that each channel defaults to 0.5 describes what happens when no Mask Map is assigned at all, which is a different question.

Ambient Occlusion and Opacity

Ambient Occlusion has no file of its own, because the Mask Map’s green lane is where HDRP reads it.

Opacity is not written as a file of its own either. HDRP reads transparency from the base color’s alpha, which is where the set’s cutout goes. The role is listed under Not written with an Add Map button.

After export

1. Select oak_bark_Normal and set Texture Type to Normal map. Apply.
2. Select oak_bark_Mask and oak_bark_Height and untick sRGB (Color Texture). Apply.
3. In the material, assign oak_bark_BaseColor to Base Map, oak_bark_Normal to Normal Map, oak_bark_Mask to Mask Map, oak_bark_Height to Height Map, and oak_bark_Emissive to the emissive map.

The panel’s Engine Import section repeats steps 1 and 2.

HDRP’s separate detail map

The detail map is a different file, and this destination does not write it. Its lanes are red desaturated albedo, green normal Y, blue smoothness, alpha normal X, with 0.5 neutral on red and blue.

A lane in the Files editor reads a whole role, a constant, or the set’s Opacity. There is no channel picker that takes one component out of a normal map, and no desaturation step, so the red, green and alpha lanes have to be prepared upstream as single-channel maps of their own before a row can write them.

Once they exist in the set as separate maps, build the file with Add Map, set each lane’s Source, and save the result as a preset. The blue lane can be filled directly, from Roughness with Transform set to Invert.

Reading it back

Point Texture Folder at the folder and set Source to Unity HDRP, or leave it on Auto.

• Mask unpacks into Metallic, Ambient Occlusion, and Roughness, with the alpha lane inverted back. The blue lane is a constant and is read as nothing.
• An empty green lane is dropped rather than imported as a fully occluded map, and is listed as Skipped with the reason why.
• A cutout in the BaseColor alpha comes back as the set’s Opacity.

References

• Mask Map and Detail Map (Unity): the Mask Map channel table and the detail mask values.
• Normal map parameters (Unity): the Y+ (OpenGL) normal convention.

Related

• Unity Built-in and URP
• Texture Sets
• Export Texture
• Texture Folder
• All texturing guides