Game Development Toolset

The Game Development Toolset is a collection of high level tools aimed to speed up games related workflows in Houdini. There are over 30 tools that range from UVing to generating Motion Vectors from simulations. 

These tools are not tied to the regular Houdini development cycle and become available the moment they are ready for testing. They are currently deployed through our github page, and will soon be updatable from within Houdini. 

Github Details

You can download the tools from our Github Repository.
There are 2 main branches 16.0 and Development. We are actively developing tools and checking them into the Development branch, so if you want the very latest, that's the place to go. Every so often we push the tools to 16.0 when we feel they are stable. 

DISCLAIMER: These tools are provided as is. We provide as much of the source as we can in order for you to troubleshoot any issues that may arise. We have developers working on these tools full time, but these tools do not fall under the regular SideFX support team.

Tools Details 

SOPs - Surface Operators 

Auto UV  

Automatically generates the seams for an object and immediately runs a UV Flatten after the fact. There are 2 main techniques: 
- Shortest Path : Uses the shortest path algorithm to define seams based on the surface's curvature
- Cluster: Subdivides the meshes into quadrants which turn into uv islands.
Tutorial Link

Calculate Curvature 
Provides 7 different ways of calculating an model's curvature. 2 built in methods and 5 other contributed by Houdini user Petz
Useful for doing procedural edge damaging and several other effects. 

Create FlowMap 
Initializes the correct attributes on a mesh in order to export a flowmap. 
Tutorial Link - All flowmap nodes

Flowmap Guide 
Uses a curve as an additional input and bends the velocity field of the flow map based on said curve. Very useful for non destructively combing the flow field.  

Tutorial Link - All flowmap nodes

Flowmap Obstacle
Uses an object as an additional input and warms the velocity field around said object. Useful for very quickly bending the flow around objects. 
Tutorial Link - All flowmap nodes

Flowmap To Color

Converts the worldspace velocity vectors into Tangent (uv) space colors. This allows the user to then bake the velocities out as vertex colors to be used in a game engine.
Tutorial Link - All flowmap nodes

Edge Group to Curve
Convert an edge selection (group) to a polygon curve. Useful if you want to sweep something along your model or many other applications.
Tutorial Link - Shown at the 5:07 minute mark 

Utility node to bring the FBX export capabilities into the SOP context. We can currently export geometry and alembic from the SOPs but we didn't have an equivalent version for FBX.  

Group Edge Loop
Procedurally generate Point, Prim and Edge Loops.  There is also an option to skip every N units, which allows for interesting results. 
Tutorial Link - Update Imminent 

Group Expand
Expands or contracts a group by a number of iterations. Positive iterations expand, negative iterations contract
Tutorial Link - Update Imminent 

Instant Meshes Bridge
Instant Meshes is a great open source Quad Remesher. This sops simply wraps around its command line interface for a more native Houdini experience.
Tutorial Link

Make Loop
Makes a Volume or a mesh with constant topology automatically loop. It does so by offsetting the animation by half and cross dissolving the animation onto itself. 
Tutorial Link

Mark Seams 
This nodes allows for a more intuitive way of managing edge groups for common workflows like UVing.
It is essentially an uber group node which lets you store selections as well as convert primitive selections into edge selections of said primitive borders
Tutorial Link

OSM Importer
Open Street Map is a great database for city street data. This node efficiently loads the OSM files into Houdini as well as all of the different tagged attributes on the buildings and streets.
Tutorial Link

Pivot Painter
Tool to generate the appropriate data necessary for Unreal 4's pivot based animation nodes. Which allows you to do complex shader animations with a very slight overhead compared to a traditional joint setup. 
Tutorial Link

Static Fracture Export 
Exports pre-fractured pieces for realtime destruction setups. Useful in Unreal's destruction System and NVidia's PhysXLab 

Unitize UVs
Simple Utility tool to make every face of a mesh to be UV'd from 0-1

UV Stacker 
Stacks similar UV shells together. Great for hair workflows and general UV management. 
Also contains some extra controls for splitting stacks randomly for variation. 
Tutorial Link

ROPs - Render Operators 

CSV Exporter
A simple example ROP to demonstrate how you can extract data from geometry and write it out with Python. The bulk of the code is in the Scripts Tab in the Type Properties Dialog. 

Games Baker
A wrapper around Mantra's baking capabilities. This node simplified the baking process by allowing you to bake the common maps easily, as well as any point attribute without additional setup. A recent upgrade allows for the baking of multiple high>low pairs at the same time, and proper compositing of the resulting textures.
Tutorial Link 

Motion Vectors
Renders out the velocity vectors to camera space, which allows them to be used as frame blending flow maps. The tutorial goes in depth on how to render them and hook them up in Unreal. 
Tutorial Link

Export a destruction sequence to FBX. It takes a packed primitive destruction setup and moves all of the point data up to object level, which allows FBX to interpret that as top level motion. Most game engines will interpret this data as a skeletal mesh animation that can be played back natively.
Tutorial Link 

Texture Sheets
This node helps with the generation of Flipbooks/Texture Sheets. Including the generation of normals (both based on the volume data as well as a traditional 6 light rig)  and the ability to channel pack your texture. 
Tutorial Link

Vector Field 
Vector Fields are velocity grids used to control GPU particles in UE4. This tool exports them to the FGA file format that Unreal consumes.
Tutorial Link 

Vertex Animation Textures
Export simulation data to texture files. This allows for very effective vertex shader playback of your high resolution simulation. There are 4 types of simulation supported

  • Consistant Topology throughout the Simulation (Soft) 
  • Packed Primitive style Rigid Body Simulation (Rigid) 
  • Changing Topology throughout the Simulation (Fluid) 
  • Camera facing cards, points moving through space (Sprite)

Tutorial Link 
Webinar Link 

Volume Textures
Converts a volume into a flipbook representation of a 3D texture. The resulting texture is usable in Ray Marching shaders which render your Houdini in Realtime! 
Tutorial Link

COPs - Compositor Operators 

Normal Color
Utility node to initialize the Color node with the proper normal map colors (128, 128, 255) 
Tutorial Link

Normal Combine  

Combines 2 normal maps together while keeping them properly normalized
Tutorial Link

Normal Invert

Inverts individual channels of the image, usually for flipping that pesky Y channel
Tutorial Link

Normal Levels  

Regular Levels operation but done in the proper -1 to 1 space 
Tutorial Link

Normal Map 

Generates a normal map from a grayscale image, with additional options to soften the normals and an intensity scale
Tutorial Link

Normal Normalize 

Ensures the image is a valid normal map with all of the 3 channels properly balanced
Tutorial Link

Normal Rotate 

Rotates a normal map while keeping the normal vectors correct
Tutorial Link


  • kevinthebright 2 months, 1 week ago  | 

    Looks like Edge Group to Curve didn't make it in the zip file?

    • lkruel 2 months, 1 week ago  | 

      They Kevin, that one is on the Development Branch. It's fairly new so we're watching for feedback

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