Performance Mode: metal builds use full-quality desktop assets

Fortnite 43.10, Windows, Performance Mode. Asset-only fix: 3 texture settings and 12 mesh LODs. No new art and no blueprint changes are needed.

The problem

In Performance Mode, wood and brick player builds switch to their simple mobile version. Most metal pieces do not: the metal wall, floor, window edits, roof edits and others keep the full-quality desktop material, textures and build animation. The wood switchback stairs edit has the same problem. Even the metal pieces that do switch load full-size 2048×2048 "mobile" textures.

How the working pieces are set up

• Mesh /Game/Packages/PBW/<Wood|Brick|Metal>/L1/PBW_<W|B|M>1_<Shape> has two material slots: [0] desktop, [1] *_Mobile.
• Quality Level Min LOD sends Low quality (Performance Mode) to a low LOD: wood LOD 2, brick LOD 1, metal LOD 3.
• That low LOD is simplified geometry UV'd for the mobile texture atlas, and its section uses slot [1].
• The blueprint (/Game/Building/ActorBlueprints/Player/<Wood|Stone|Metal>/L1/PBWA_*1_*) maps each static material to its animating version, so the build and damage animations follow whichever material the visible LOD uses.

Good examples to copy: PBW_M1_HalfWall and PBW_M1_StairW (LOD 3 uses slot [1] Metal_lvl1_Static_INST_Mobile), PBW_W1_Solid, PBW_W1_StairT.

Fix 1: reduce the metal mobile textures

Open each texture in the Texture Editor and set Details → Level Of Detail → LOD Bias = 2 (2048 → 512, same as wood), then save.

For comparison: wood T_PBW_W1_Mobile_D/N/S are 512 (LOD Bias 2), brick Brick_Wall_Mobile_D/N are 512 (LOD Bias 1).

Fix 2: give 12 meshes a working mobile LOD

A = the mobile slot exists but no LOD uses it. B = there is no mobile slot. On all 12, every LOD uses slot [0] (desktop).

Important: these low LODs are decimated copies of the desktop mesh, UV'd for the desktop atlas. Only re-pointing the section to the mobile material gives a scrambled texture. Each mesh needs a real mobile LOD like its working siblings.

Steps in the Static Mesh Editor, for each mesh above:

1. Problem B only: Details → Material Slots → +, set the new slot [1] to /Game/Packages/PBW/Metal/Materials/Metal_lvl1_Static_INST_Mobile (wood: /Game/Packages/PBW/Wood/Materials/Wood_lvl1_Static_mobile).
2. Author the mobile LOD the same way as the working siblings: simplified geometry with UVs for the mobile atlas (T_PBW_M1_Mobile_* / T_PBW_W1_Mobile_*). Import it at the Perf LOD index (LOD Picker → Custom → LOD N → Import LOD).
3. LOD N → Sections → Section 0 → Material = slot [1]. For PBW_M1_Floor do LOD 3 and LOD 4.
4. Leave Quality Level Min LOD as it is, then save.

Build and damage animations

No blueprint change is needed. All level-1 build blueprints already map *_Static_INST_Mobile → *_Wall_Mobile (and *_Wall_Damaged_Mobile), for example PBWA_M1_Solid: Metal_lvl1_Static_INST_Mobile → Metal_lvl1_Wall_Mobile. Once a mesh's Performance Mode LOD uses slot [1], its build and damage animations switch to the mobile versions automatically. The new mobile LOD's UVs must also fit Metal_lvl1_Wall_Mobile / Metal_lvl1_Wall_Damaged_Mobile (same atlas, build mask T_PBW_M1_Mobile_M).

Optional

No door mobile texture has a LOD Bias (wood T_PBW_W1_Door_Mobile_* 1024×2048, brick Brick_Door_Mobile_* 1024, metal T_PBW_M1_Door_Mobile_* 2048). If doors are not meant to stay sharper, give them the same LOD Bias.

Delivery

This is an asset-only content change, so it can't ship as a hotfix, but it is a small download that can go into any regular update.

Images

Every build shape in wood, brick and metal, at full quality (DX12, LOD 0) and as Performance Mode draws it (the real Perf LOD with the shipped materials). Working metal pieces show the green mobile panels; broken ones keep the colorful desktop patchwork. Click any row to view it full screen.

Walls and wall edits

Doors, arches, brace

Floor and floor edits

Ramp and ramp edits

Roofs