Unity Houdini Geo Importer/Exporter

Based on Waldo Bronchart's unity-houdini-geo-importer

Imports and exports .geo files. Quickly and conveniently passes points with attributes between Unity and Houdini.

Dependencies: JsonDotNet

Overview

Editor Scripts

HoudiniGeoAssetPostProcessor.cs   listens for .geo file changes
HoudiniGeoExtensions.cs           editor-only HoudiniGeo helper methods
HoudiniGeoFileInspector.cs        custom inspector for .geo files
HoudiniGeoFileParser.cs           .geo file json parser
HoudiniGeoFileExporter.cs         .geo file json exporter
HoudiniGeoInspector.cs            HoudiniGeo asset inspector

Runtime Scripts

HoudiniGeo.cs                     custom unity asset to represent .geo parsed file contents
ExamplePointDataExporter.cs       Example of how to quickly export points with attributes to a .geo file

Example

Creating a Point Data Class

You can serialize any class inheriting from PointData. Define a field per attribute. Any public field or private field annotated with [SerializeField] will be saved. Supported field types are float, int, string, Vector2, Vector3, Vector4, Vector2Int, Vector3Int and Color.

public class ExamplePointData : PointData
{
    public string name;
    public int index;

    public ExamplePointData(Vector3 p, string name, int index) : base(p)
    {
        this.name = name;
        this.index = index;
    }
}

Saving Point Data to a .GEO file

Add your PointData objects to a PointDataCollection (basically just a List) and call ExportToGeoFile(string path) on it.

Reading Point Data from a .GEO file

If you have a reference to a HoudiniGeo object, you can call GetPoints<PointType>() on it and get a PointCollection<PointType> from it.

Suggested Uses

Lightweight solution for sharing custom scene metadata with Houdini.
- e.g. telling it where hand-placed objects are so procedural effects like grass can avoid it.
Lightweight solution for exporting point data to Unity and instantiating Unity prefabs there. Procedural placement without generating any new geometry assets!
- e.g. generating points where you want to place trees, but placing them as prefabs so they have re-usable meshes that can be GPU instanced.

To Do

Exporting primitives is not yet implemented. Shouldn't be too hard to add but I'm not going to be using it!
The importer doesn't distinguish between 32-bit and 64-bit yet so for now floating points are always exported as 64-bit.
GEO files seem to have a lot of duplication and little quirks that I couldn't find any documentation on. I replicated the behaviour best I could and marked anything I found odd with a comment. If you have a non-standard use case and something isn't exporting quite right, have a look at HoudiniGeoFileExporter.cs!

Contact

Waldo Bronchart (importer)

wbronchart@gmail.com

Roy Theunissen (exporter and PointData/PointDataCollection functionality)

roy.theunissen@live.nl

RoyTheunissen/Unity-Houdini-GEO-Import-Export