GeoExport

The GeoExport node exports a stage to .usd, .usda, .usdc, .abc, .fbx, .obj, .ply, .splat, and .spz files.

When exporting to USD, in the Export Method dropdown, select Flatten All to export your entire stage as flattened, or Flatten Sublayers, Keep References, to export scene modifications as "overs". By using the Flatten Sublayers, Keep References option, this preserves existing composition arcs from imported stages and is more lightweight when round-tripping with other departments. You can use this in combination with the GeoBreakLayer node, which acts as a breakpoint in your node graph, to define which changes are written to the sublayer file when you export. For an example of this workflow, see Export From Your Scene.

Note that if GeoBreakLayer node(s) are present in the Node Graph, only the scene composition between the bottommost GeoBreakLayer node(s) relative to this GeoExport node will be exported. This behavior applies to all file formats.

Note:  Writing the whole flattened stage is not a common workflow unless you are creating a stage from scratch with Nuke nodes.

Tip:  GeoExport's classic 3D system equivalent is the WriteGeo node.

Note:  The export of .ply files is intended for the export of Gaussian Splats but it also supports exporting meshes. However, note that the two cannot be combined - i.e. you can't export a scene which is a mix of meshes and splats.

Note:  Skew and non-uniform scales applied to Gaussian Splats will introduce artifacts into higher-order spherical harmonic data, when exporting to the .ply file format.

Inputs and Controls

Connection Type	Connection Name	Function
Input	unnamed	The previous stage in the scene you want to flatten and export.

Control (UI)	Knob (Scripting)	Default Value	Function
GeoExport Tab
Format	file_type	abc	Specifies the file type for export. Select from .abc, .fbx, .obj, .ply, .splat, .spz, .usd, .usda, .usdc files. The available formats depend on the USD file format plugins that are available. Non-USD file formats (e.g. ABC, OBJ, FBX) may have limitations in what they can represent, depending on the format specification and file format plugin implementation. If there is a requirement for prim paths to be preserved when reimporting, or exporting of USD concepts not supported by the format/plugin (e.g. over prims), then USD formats (e.g. USD, USDA, USDC) should be used.
File	file	none	Specifies the file path to where the stage is written, including the required file format.
Stitched Export	stitched_export	on	Export frames individually then stitch them together into a single file. This can be used to reduce memory usage when exporting large animated scenes at the cost of longer export times. This will produce the same results as a non-stitched export.
Execute	Execute	N/A	Click to write the stage to disk.
ABC Options
Bake Transform Operations	bake_xform_ops	off	Pre-bake custom-suffixed xformOps (e.g. xformOp:transform:NodeName) into the canonical unsuffixed form (xformOp:transform) before export. This ensures the Alembic writer can extract the composed local transform.
PLY Options
Spherical Harmonics	ply_spherical harmonics	3	Select either 0, 1, 2, or 3 for the amount of spherical harmonics to export.
Export Hidden Objects	ply_export_hidden_objects	off	Select this checkbox to enable or disable exporting hidden objects in the .ply file.
SPLAT Options
Export Hidden Objects	splat_export_hidden_objects	off	Select this checkbox to enable or disable exporting hidden objects in the .splat file.
SPZ Options
Spherical Harmonics	spz_spherical harmonics	3	Select either 0, 1, 2, or 3 for the amount of spherical harmonics to export.
Export Hidden Objects	spz_export_hidden_objects	off	Select this checkbox to enable or disable exporting hidden objects in the .spz file.
USD Options
Export Method	export_method	Flatten Sublayers, Keep References	Choose the export method for exporting to a single file. Flatten All - flattens the entire stage, including all sublayers and references, into a single layer to export. Flatten Sublayers, Keep References - flattens the stage’s root layer but does not flatten composition arcs, such as references, payloads, inherits, specializes, or variants.
Format	usd_file_format	ASCII	Select either ASCII or Crate format for the exported USD file.
Python Tab (These controls are for Python callbacks and can be used to have Python functions automatically called when various events happen in Nuke.)
Before Render	beforeRender	none	These functions run prior to starting rendering in execute(). If they throw an exception, the render aborts.
Before Each Frame	beforeFrameRender	none	These functions run prior to starting rendering of each individual frame. If they throw an exception, the render aborts.
After Each Frame	afterFrameRender	none	These functions run after each frame is finished rendering. They are not called if the render aborts. If they throw an exception, the render aborts.
After Render	afterRender	none	These functions run after rendering of all frames is finished. If they throw an error, the render aborts.
Render Progress	renderProgress	none	These functions run during rendering to determine progress or failure.