FBX Import Window - Houdini online help

Overview

FBX (sometimes called “Filmbox”) is an interchange file format used to move 3D animation data between software packages.

This is a new feature in Houdini 9.1. To learn about more new features, see what’s new in Houdini 9.1.

Choose File > Import > FBX (Early Access).
Click the chooser button next to the File field and choose the file you want to import.
Click Import to replace the current scene, or Merge to merge the imported data into the current scene.

Note

To properly export vertex caches from Maya™, the “Export Quick Select Set as Geometry Cache File(s)” option needs to be checked.

Exporting point animation from Maya

To export animated point data, you will need to create a vertex cache in Maya. A vertex cache is a set of files that defines positions for every vertex of the geometry at every frame over an animation interval.

To do this in Maya, select the object whose points you have animated, make sure the main menu type is set to “Animation”, and in the menu, go to “Geometry Cache->Create New Cache”. It is also highly recommended to ensure that the cache type is set to “Double” before create the cache. To do this, click on the options box next to the “Create New Cache” menu item, and make sure that the “Store points as” option is set to “Double”.

Once you have your geometry cache, you can export it to FBX. When doing so, make sure that the “Export Quick Select Set as Geometry Cache File(s)” exporter option is checked, otherwise Maya will ignore all vertex cache information.

Filter options

Cameras	Import cameras.
Joints and Skin	Import joints, bones and skinning information.
Geometry	Import geometry - meshes, triangulated NURBS, etc.
Lights	Import lights.
Animation	Import animation, including vertex cache files.
Materials	Import materials and textures.

Animation options

Resampling

This menu determines what animation curves are resampled, as well as the frequency of resampling.

For example, if the curve is to be sampled at every frame, set the sampling frequency parameter to 1. If the curve is to sampled once every two frames, set this parameter to 2, and so on.

Resample TCB Curves Only	Only curves exported as TCB (Tension-Continuity-Bias) types will be resampled. This is the default setting since native TCB curves are currently not supported.
Resample All Cubic Curves	All cubic curves will be resampled down to linear key interpolation.

Override FBX Frame Rate

If checked, the frame rate stored in the FBX file will be ignored, and the one provided by the user will be used instead. This is useful if an application that exported the original file did not set the frame rate correctly.

Material options

Import Materials As

This option determines how materials will be imported.

FBX Shader Nodes	Each material’s surface is represented as a special VEX FBX Shader with standard parameters such as diffuse, ambient, emissive, etc. components.
VOP Networks	Each material’s surface is represented as a VOP shader network constructed from various VOP nodes. While parameters similar to the ones in FBX Shaders are exposed, individual shader components inside the shader can be rearranged and edited as the user desires.

Compatibility options

Compatibility Mode

Determines how values in FBX nodes are interpreted. Some exporters output information differntly from what the FBX standard dictates, and thus workarounds for these issues are often useful. This menu allows the user to choose which set of workarounds, if any, is to be used on import.

FBX Standard	FBX data is interpreted in strict accordance with FBX rules and documentation. Files from FBX exporters which output anything other than what FBX standard dictates may look incorrect on input.
Compatible with Maya	FBX data is interpreted as coming specifically from the Maya™ FBX exporter, and adjustments are made appropriately in order to make the imported scene look exactly as its original source in Maya™.

Single-Precision Vertex Caches

Forces the importer to treat all Maya™ vertex cache files as if they were exported with single-precision (float), instead of double precision. This is necessary since FBX SDK incorrectly imports any single-precision vertex cache files.

Triangulate NURBS and Patches

Forces the importer to triangulate NURBS and patch surfaces. If unchecked, patches are converted to NURBS on import. Note that information such as skinning and vertex caches will not be preserved on these objects.

Import Global Ambient Light

Allows importing the single global ambient scene light. This light exists in addition to any lights defined in the scene; however, some FBX exporters do not set it correctly, in which cases it may be useful not to import it.

If objects with geometry caches look extremely distorted, try turning this option on.

Import Blend Deformers as Blend SOPs

If checked, any objects with Blend deformers on them will be imported as Blend SOPs. Otherwise, blend deformations will be imported as channels.

The main advantage of importing blending as SOPs is the resulting flexibility to adjust blend targets' geometry and blend weight values; however, there is a possibility that blending animation will not be exactly the same as that of the original file.

General options

File Paths

Determines how file paths to textures and the original FBX file are set on import.

Keep Absolute

All paths are stored as absolute paths. If any referenced files are moved, paths in the saved scene will need to be changed by hand.

Convert to Relative

The importer will attempt to convert all paths to relative paths. If the FBX file is merged with the current scene, all paths will be made relative to the current location of the Houdini scene file. If the FBX is replacing an entire scene, all paths will be made relative to the location of the FBX file. Note that this requires the resultant Houdini scene to be saved into the same directory where the original FBX file is located.

Unlock Geometry File SOPs

Leaves all imported File and Capture SOPs unlocked after import. This means that FBX geometry is referenced from the original FBX file on disk, and is not stored in Houdini HIP file. Note that for skinned objects, point weights will not be re-imported when the File SOP re-cooks, and are always stored as a copy in the Override SOP.

Unlock Deformation File CHOPs

Leaves all imported File CHOPs, which are responsible for deformations such as blending and vertex caching, unlocked after import. This means that deformation data is referenced from the original FBX file on disk, and is not stored in Houdini HIP file.

Import Null Nodes as Subnets

If checked, all grouping null nodes will be imported as subnets, and their children will be placed inside of each subnet. Note that nodes which represents joints in a skeleton will still be imported as nulls, regardless of this option’s value.

Import Directly Into /obj Network

If checked, imports all geometry and objects from the current FBX file directly into /obj network, instead of creating a separate subnet per FBX file.

Convert to Y-up Coordinate System

If checked, the entire FBX scene will be converted to the Y-up coordinate system. If unchecked, the scene will be imported as-is.