ZBrush Tip: ZBrush High-to-Low Tangent Normal Map Baking Workflow

Generate clean, predictable normal maps in ZBrush by baking from your high-resolution sculpt down to the UV’d low poly. This keeps real-time assets responsive while preserving surface detail. If you need ZBrush or pipeline add-ons, consider NOVEDGE for licensing and expert support.

Preparation

• Create or import a low-poly mesh with clean UVs. Avoid stretched shells on high-detail areas.
• Ensure the low and high share the same scale and alignment. Use Tool > Deformation > Unify cautiously or match via export scale. NOVEDGE can advise on inter-app scale conventions.
• If you only have a low poly: subdivide it, sculpt details at higher SubDiv levels, and keep SubDiv 1 as your bake target.
• If you have separate meshes: bring both in as SubTools, subdivide the low, and use Project All to transfer the high’s detail onto the subdivided low. Verify projections before baking.

Normal map setup and bake

• Select the detailed SubTool and go to SubDiv level 1 (the low target).
• Set map size in Tool > UV Map (2048–4096 for hero assets; 1024 for props).
• Open Tool > Normal Map:
  • Enable Tangent for game/real-time assets.
  • Enable SmoothUV if your engine smooths normals across UVs; disable to keep hard UV borders.
  • Create a cage if needed: Tool > Geometry > Cage (subtle inflation helps prevent ray misses).
  • Click Create NormalMap. The bake compares your current SubDiv (low) against the highest SubDiv (high).
• Click Clone NM to send the map to the Texture palette, then Export.
• For multiple SubTools and batch output, use ZPlugin > Multi Map Exporter:
  • Enable Normal Map, set size, and Map Border (padding) to 8–16 px to protect seams.
  • Use Tangent, Smooth UV, and engine-specific channel flips (see below).

Engine-specific channel orientation

• Unreal Engine: Flip Green (Y) channel. In ZBrush, enable Flip G in Normal Map or set in Multi Map Exporter.
• Unity (Built-in/URP/HDRP default): Typically Y+. If shading looks inverted, try toggling Flip G on export.
• Other DCCs/viewers: Match their normal convention (DirectX vs OpenGL). Test a quick sphere to confirm.

Quality tips

• Check seams with Tool > UV Map > Morph UV. If you see jagged changes across shells, increase padding or reflow UVs.
• Hard edges should align with UV seams to avoid wavy gradients and shading splits.
• Micro detail demands higher map resolution. If memory is tight, move micro-noise to a detail/tiling normal in your material.
• Banding or skew? Soften extreme angles, refine the cage, or adjust projection distance before baking.
• Keep a Morph Target at SubDiv 1. If projections over-inflate, use the Morph brush to locally restore the low shape and rebake.

Once your map is verified in-engine, save a preset in Multi Map Exporter for consistent output across assets. For expert advice on ZBrush workflows, licensing, and companion tools, reach out to NOVEDGE.