What does the tool currently do?
One of the main things the tool does is generate corrective morphs optimised for the linear skinning used in most game engines such as Unreal Engine and Unity. Corrective morph generation is completely customisable. You can generate as many as you require for your specific circumstances. Hero characters can have hundreds of corrective morphs whereas NPC might only require a few key morphs for knees and elbows etc.
Unlike other methods which tend to rely on ray-casting or similar processes, the method I'm using is FAST. The tool is able to generate over 230 corrective morphs on a subd-1 character with clothing (approximately 182,000 polygons in total) in around 82 seconds on my rig.
Corrective morph groups can be generated as either additive morphs (generally better suited for using a bone driven controller in Unreal I've found) or individual morphs (generally better suited for using with the pose driver node in Unreal). Currently I use a mix of both depending on the joint.
Other tasks the tool can currently assist with include:
- Renaming and reparenting bones to match a target skeletal structure, such as the Unreal Engine Manny skeleton. It can also add the missing IK bones used by a target skeleton.
- Correcting joint orientations to match those of the target skeleton.
- Packing selected UV islands into a single udim. For example, with Genesis 9 figures I usually pack the head, body, arms and leg UV's and textures into a single udim to optimise materials inside a game engine.
- Optimising materials by combining multiple materials from Daz into one material inside a game engine.
- Altering the Daz eye geometry and UV's to work with the Metahuman eye shader in Unreal Engine.
- Experimental clothing occlusion culling. This can automatically delete parts of the characters body that are occluded by clothing. This can help to reduce the final poly-count and also prevent the characters body from poking through the clothing on some poses.
- Transfer retargetting poses from Daz Studio onto the target skeleton.
- Transfer any number of additional morphs, such as facial expressions, visemes etc onto the character.
- Transfer any number of animations from Daz Studio onto the target skeleton and export them for use inside a game engine.
Other functionality on the roadmap:
- More fine grain controls over occlusion culling.
- Mesh reduction and LOD generation
- Ability to generate texture atlases based on the UV's you've defined. At the moment the tool only changes the UV's. The textures have to be created using another tool such as Photoshop.
- Ability to generate alembic hair grooms from Daz fibre mesh hair or hair cards. This will be challenging but some initial testing looks promising.
- Ability to animate the character using a control rig inside Houdini and exporting that animation out to a game engine.
Keep an eye on the Daz forum for updates: https://www.daz3d.com/forums/discussion/619356/powerful-new-houdini-tool-for-getting-realistic-daz-figures-into-game-engines#latest [www.daz3d.com]
