Convert a bump map to a normal map

The Paint Layers window lets you convert a bump map to a normal map.

You can then (optionally) combine the converted normal map with other normal map layers, effectively combining painted bump map detail with extracted normal map detail to produce a single map. This can be useful when you want to create detail using both normal and bump maps, but you need a single map suitable for use in a game engine.

To convert a bump map to a normal map

1. Create or import your bump map as a paint layer.

   For example, do either of the following:

   • Create a new paint layer and set the Channel to Bump Map, then paint on a model to create your map. (Paint with dark colors to create the illusion of indents, paint with light colors to create raised areas.)
   • In the Paint Layers window, select Import Layer, navigate to select a bump map, then specify Bump Map in the Select Channel option that appears.

2. Right-click paint layer containing your bump map, then select Normal Map from Bump from the menu that appears.
3. In the Normal Map From Bump options that appear, set the Coordinate Space and Compatibility options you want for the normal map, then click OK.
   

   Mudbox converts the bump map layer to a normal map layer and adds it to the Normal Map channel. (By default, the new layer is named after the original bump layer and appended with 'NORMAL'.) The original bump map layer is unchanged.

4. (Optional) Set the blend mode for the converted normal map layer to Overlay or Hard Light so you can see the combined effect.

   In many cases, the newly converted normal map layer overrides any existing normal detail on lower layers. Adjusting the blend mode lets you view the combined effect.

To combine the converted normal map with an existing normal map

1. In the Paint Layers window, under the Normal Map channel, ensure that only the layers containing normal maps that you want to combine are visible (including the converted bump map).
2. Right-click any layer or click the Layers window menu button , then select Merge Visible.

   Mudbox combines the normal map layers into a single layer, which you can then export. (See Save or export paint layers.)