Houdini 20.5 Nodes Geometry nodes

Labs Unreal Pivot Painter 1.1 geometry node

Pivot Painter stores model pivot and rotation information for geometry used in a shader.

Pivot Painter is a sop that stores model pivot and rotation information in the model’s vertex data and additional UV channels for PP1, and in textures for PP2. That information can then be used inside of Unreal’s shader system to create interactive effects. This tool is specifically built to work with the material functions provided by Epic Games in Unreal Engine. It is however possible to use this encoded information in other engines such as Unity, since it uses common attributes and textures. https://docs.unrealengine.com/en-US/Engine/Content/Tools/PivotPainter/index.html

Tip

Important pivot attributes are: N and name for PP1. N and hierarchy for PP2.

Important geometry attributes are: UV and name for PP1. UV and hierarchy for PP2.

Important optional attributes used for PP2 when using the “Selection Order” is the selectionIndex attribute. This integer attribute starts at 0.

It is now also possible to provide an up attribute on the pivot points, which will be used in the tangent calculations instead of trying to generate them. If you have an up vector already, it is highly recommended you provide it.

Tip

An important update made to this tool requires you to no longer scale up the input geometry and pivots 100× before the tool. The tool does this for you now.

Parameters

Export

Pressing this button will compute all data and export the required files to disk.

Mode

Allows for specifying what method should be used to encode pivot information for the given geometry and pivots. See the Epic Unreal Engine documentation for specifics and difference.

Asset Name

The name used for the asset that will be exported to disk. This name will be used for the FBX and optional textures.

Output Directory

The directory in which the generated assets will be exported.

Account for UE FBX Force Front X-Axis

Negates the rotation on meshes that have Force Front Axis enabled in Unreal.

Restore Input Scale

This toggle controls if the output of this sop should restore the geometry to Houdini units. This does NOT affect the exporting process of the node, and is only really useful if you want to do further processing on the geo before exporting.

Data Packing Method

This menu determines if the tool should encode PivotPainter information in the default way, or based on a custom configuration.

Layout Lightmap UVs

This forces the tool to automatically generate Lightmap UVs based on the primary UVs.

UV Padding

This controls the padding applied to the Lightmap UVs while they are laid out.

Range

Custom range used for encoding extents channels with. Previously this was hardcoded to 2048 (like in 3dsmax) Lowering this number will give you far superior precision, and this change is coming to the max plugin soon too.

Texture #

RGB

Controls the type of information that will be encoded in these channels. The value you choose highly depends on your shader in engine.

A

Controls the type of information that will be encoded in this channel. The value you choose highly depends on your shader in engine.

Per Object

Custom Attribute for Random Value

Turning this on will use the specified attribute for the random data instead of generating it.

Custom Value Attribute

The float attribute name used to encode a value in the random slot.

Pivot Position

The attribute components used to encode Pivot Position.

Forward Axis

The attribute components used to encode the Forward Axis.

Random Value

The attribute component used to encode a random value.

Motion Mask

The attribute component used to encode the Motion Mask.

Hierarchical

Leaf Pivot Position

The attribute components used to encode the Leaf Pivot Position.

Branch Pivot Position

The attribute components used to encode the Branch Pivot Position.

Branch Angle

The attribute components used to encode the Branch Angle.

Use Mask

This toggle enables/disables the use of vertex colors for the motion mask of the object.

Input Data

This menu allows you to control if you want the tool to try and generate pivot positions, or if you want to use your own.

Branches Group

The primitive group containing the branches geometry.

Leaves Group

The primitive group containing the leaves geometry.

Geometry nodes