After you have separately exported geometry and animation FBX files,
you need to adjust specific settings when you want to import them into Unreal,
especially when the model contains Opacity texture
settings.
Exporting Assets from 3DXchange
Please follow the steps below to export assets (props and any types of characters) into FBX for Unreal.
Add an asset contains Opacity textures (in this case,
the hair, eyelashes and the corneas) to 3DXChange (in this case, standard character).
Click the Export FBX (Shortcut: Ctrl + X) button to export the assets as
character and animation files in FBX format.
In the Export FBX panel, make sure you select the GameEngine_Unreal preset from the Target Tool Preset drop-down list.
Separately export the model and its animation as isolated files.
Loading Geometry FBX Files with Opacity Textures
Drag and drop the model FBX into the Content Browser panel.
Unreal prompts you an Import Settings dialog.
You MUST activate the Use TOAs Ref Pose box in order to load and apply the T Pose
(from 3DXchange first frame) to the character.
Make sure the Import Materials and Import Textures are activated.
Click the Import button to load the character into the Content Browser.
If you double click on the model
asset, you will see the incorrect results for the meshes applied with
opacity textures (hair, eyelashes and the corneas).
Double click on the material the appears incorrect (in this case, the material of the hair)
in the Mesh Details panel.
You will see the hypershade graph of the material.
Change the blend mode to Masked in order to activate the Opacity Mask radio button for the right block.
Drag and drop to connect the opacity channel from the left block to the right one to send the opacity texture to the mesh.
Click on the Apply button to compile the shader again. The hair of the character turns to be well-trimmed. However, the sides
face inward appear transparent because the negative normal direction of the mesh.
Activate the Two Sided box.
Click the Apply button on the toolbar.
The mesh will be correctly rendered with the adjusted material.
Repeat the same steps to the materials that contain opacity textures and apply the change again.
Note:
Please note that the Two Sided setting is optional.
Loading Motion FBX Files to Unreal
If you want to load motion FBX files exported from 3DXchange to Unreal, then you just need to
define the skeleton the motions are about to be applied to.
Drag and drop the motion FBX file or files onto the Content Browser panel.
Select the target skeleton for applying the motions when you are prompted with the FBX Import Options panel.
Click the Import button at the bottom of the FBX Import Options
panel to load the file as motion assets into Unreal.
