Export from form•Z
From the form•Z main menubar, select File > Export > Twinmotion. The exported file will have the extension .udatasmith. This file contains the scene hierarchy, material descriptions, and lights information in text format. An assets folder will be created alongside the udatasmith file. This folder contains a binary representation of each object’s geometry (“MESH”), and texture maps.
Explanation of export options:
Objects: Object Actor Hierarchy
form•Z has two ways to hierarchically organize objects: Groups (in the Objects Palette) and Layers (in the Layers Palette). Twinmotion has only one method of organization, called the Scene Graph.
Flat: No object hierarchy in the Scene Graph. All objects will be placed in a single root group.
From formZ Groups: The Twinmotion Scene Graph will follow the group structure from the form•Z Object Palette
From formZ Layers: The Twinmotion Scene Graph will follow the layers structure from the form•Z Layers Palette.
Materials: Double Sided
In form•Z, surface objects are always visible from both sides. In Twinmotion, this is not the case. By default, only the surface’s normal side will be visible, which may cause an issue where certain surface objects are ‘missing’ when viewed from the back side.
The solution will depend on the needs of your project. If there are surface objects that need to be seen from only one side (like a ground plane), but are currently invisible in Twinmotion, use form•Z’s Reverse Tool to flip the normal of the object.
However, if there are many surface objects that need to be seen from both sides (like glazing made with rectangles), then you can instead enable the Twinmotion Double Sided materials option. Double Sided materials are somewhat less efficient than single sided materials.
Lights: Intensity Scales
form•Z basic light types express intensity as a (unit-less) percentage. Twinmotion Distant and Point/Cone light types express intensity in terms of lux and candelas, respectively. Upon export, form•Z’s percentage is multiplied by the value provided in the number box.
Import into Twinmotion
- In Twinmotion, select File > Import from the main menubar, or click on the Plus Button located under the import pane.
- In the resulting modal dialog, select the Geometry tab, then click Open to select the udatasmith file saved earlier.
- Click the Options button, the select one of the options under Collapse:
Keep Hierarchy: This will retain the form•Z Group or Layer organization specified during the export process. Choosing this option retains the ability to transform individual form•Z objects.
Collapse By Material: This will merge all objects with the same material into a single mesh. Choosing this option will result in significantly better viewport performance on heavy files.
Collapse All: All objects are merged into a single mesh. - Click the Import button to confirm.