UV unwrapping for PBR textures is how albedo, roughness, and normal sit on the mesh. Bad UVs stretch grain, flash seams, and waste 4K maps. Good UVs hide cuts, keep pixels per meter even, and let a Locker3d tile look like a real surface. This is a practical unwrap checklist for Blender, with notes that still apply when you export to Unreal or Unity.

Why PBR is unforgiving of UVs

A painted diffuse can hide stretch. A PBR normal cannot: stretched UVs smear the blue/purple lighting and the roughness highlights stretch with it. Seams that sit on a silhouette show as a roughness or normal break even when the albedo almost matches. If you do not know the maps yet, read the complete PBR textures guide first, then unwrap with those maps in mind.

Seams, islands, and texel density

Mark seams where a real object would have an edge: under a table top, inside a door rebate, at a roof ridge. Unwrap (U → Unwrap) and check the UV Editor with a checker or the actual albedo. Pack islands with consistent scale. Texel density is pixels per meter: a 2K texture on a 2-meter plane is 1024 px/m. Keep hero furniture near that range; let distant walls drop. In Blender, add-ons or a simple “average island scale” pass stop a chair leg from eating half the 0–1 square. Leave a few pixels of padding so mipmaps do not bleed one island into another.

  • Hide seams on back faces and inner edges.
  • Keep island scale even across objects that sit in one shot.
  • Do not overlap islands unless you intend mirrored detail.

Tiling materials versus unique unwraps

Floors, walls, and roads often need only a clean quad unwrap: one island, UVs larger than 0–1 so the texture repeats. Scale in the Mapping node after you apply the maps with the Blender PBR steps. Unique assets (hero props, baked trim, labels) must stay inside 0–1 without overlap. Do not mix both on one UV set without a plan: a tiling wood floor should not share an atlas with a unique sofa label. For seam-free repeats, see how to tile textures without seams.

Checks before you light the shot

Apply the Locker3d albedo only. Orbit the camera: stretch shows as warped grain. Switch to the normal: a visible line is a seam or a split normal. In Edit Mode, look for stacked islands and for faces still using the default unwrap from a primitive. Apply object scale before unwrap or every island will be wrong after you apply scale later. Shade Auto Smooth so the normal map is not fighting hard vertex normals on a bevel.

When triplanar is the better UV

Rocks, cliffs, and imported CAD blobs often cost more to unwrap than they are worth. Triplanar projects from X, Y, and Z and blends by normal. It is documented in triplanar mapping for seamless textures. Skip it for wood grain, type, and anything that must follow a plank direction. Grab test maps from wood, concrete, or stone in the catalog. Locker3d is CC0, so you can bake the result into a unique UV later; see CC0 textures: what you can and cannot do. More unwrap notes live on the blog.

Keep material UVs and lightmap UVs apart in game exports. Channel 0 can tile past 0–1 for a Locker3d floor; channel 1 must stay unique and packed for the lightmap. Overlapping islands on the lightmap channel cause blotches that look like a broken albedo. In Blender, create a second UV map before you export to Unreal. Name it clearly. Do not “apply” a tiled mapping into the lightmap UVs. If a hero prop will be baked, unwrap it unique first, then you can still tile a trim on a second set.

Frequently asked questions

Do tiling PBR textures still need a UV unwrap?

Yes, unless you use triplanar or box mapping. A simple unwrap (or even a cube project) lets you set scale. Unique trim and baked details need a careful unwrap.

What is texel density and why does it matter?

Texel density is pixels per meter on the mesh. If a door uses 4K on a tiny island and a wall uses 1K on a huge island, the wall looks soft next to the door.

When should I skip UVs and use triplanar?

Use triplanar on rocks, terrain, and CAD junk where seams are worse than blend artifacts. Do not use it on wood planks, text, or roof tiles that must follow a direction.