Creating Displacement Maps

From ZBrush Info

A displacement map is a texture, just like bump and normal maps, therefore your model will need to have UV coordinates set up so that your 3D animation and rendering software can apply the displacement map correctly. UV coordinates can be created in ZBrush using the tools in the Texture section of the Tool Palette (Tool:Texture), however ZBrush 's automated UV tools will create coordinates that may be less than ideal if further texture editing is required in a paint program such as Photoshop. It may be preferrable to create UVs outside of ZBrush and then import them with your model.

This section will describe how to create and export displacement maps using the tools available in the Tool Palette. You also have the option of exporting the displacement map using the Displacement Exporter which time and effort when optimizing your displacement map for use in your particular 3D animation and rendering software (Maya, 3D Studio Max, XSI, etc.). This tutorial assumes that you have reached a point with your model where you are happy with its form and level of detail and you wish to see the model rendered in your animation and rendering software so that it looks just like it does in ZBrush . Therefore your model should have several levels of subdivisions in ZBrush before you begin this process.

To create a displacement map follow these steps:

1. Draw your model on the canvas. The image below shows the model ready for a displacement map to be created from the details sculpted int the surface.

2. Ensure that the model has UV coordinates, you can check this using the Tool:Texture:Uv>Txr button which will create a color texture and apply it to the model revealing how the UVs are layed out. If you are satisfied with the UV coordinates you can switch the texture back to Texture Off in the Texture palette. The image below shows how the UVs are laid out for this model using the Uv>txr option.

3. Set your model to the lowest subdivision level in the Tools:Geometry section of the Tool palette.

4. In the Tools:Displacement section of the Tools palette, set the sliders to the desired values for the displacement map you're about to create:

• DSubPix - controls the accuracy of the map. Higher values result in a more accurate map that may take longer to generate.

• DPRes - sets the resolution of the displacement map. These maps will always be square in shape so one slider value controls height and width.

• Adaptive - Adaptive Scan Mode generates a map that is more accurate in detailed areas. If you are creating a matching normal map, make sure that this setting is consistent with your settings in the normal map sub-palette. Activating this option overrides the DSubPix setting.

• SmoothUV - Ensures that UVs are smoothed when the map is created. This reduces the chance that a grid pattern will appear in the displacement map.

• Intensity - Sets the strength of the map. The settings in your 3D animation package will also affect map intensity. You should try and be consistent when creating multiple maps for one or more objects in the same scene.

• Mid- Sets the mid level gray value of the map. The default value of 50 ensures that gray areas of the map have little displacement, dark values create cavities and light areas create bumps. Different 3D software packages interpret these values in their own way. Its best to consult your 3D animation package's rendering document to guarantee the best results.

• Mode-Activate this button to make sure the resulting texture is a displacement map. If this button is not on the texture created will be a bump map and your model will not displace correctly.

Once these settings have been adjusted to your satisfaction press the Create Displacement Map button. It may take some time depending on the detail of your model and the resolution of the final map. Once created the map will appear in the Alpha palette. You can export it directly from the Alpha palette or use the Displacement Exporter plug-in to optimize the map for use in your particular 3D animation and rendering software. The image shows a preview of the displacement map in the Alpha palette.

The Apply Displacement button applies the current alpha as a displacment map to the model. If the Intensityslider is at zero this button will be unavailable. This will not affect the displacement map you have created already but it is an option that can allow you to deform your model based on the current alpha.

To Learn About Displacement Maps Click Here.

To Learn About Displacement Exporter Click Here.